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The Asymmetrical Brain

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The Asymmetrical Brain
edited by Kenneth Hugdahl and Richard J.
Davidson
A Bradford Book
The MIT Press
Cambridge, Massachusetts
London, England

(2003 Massachusetts Institute of Technology
All rights reserved. No part of this book may be reproduced in any form by any electronic
or mechanical means (including photocopying, recording, or information storage and re-
trieval) without permission in writing from the publisher.
This book was set in Palatino on 3B2 by Asco Typesetters, Hong Kong and was printed
and bound in the United States of America.
Library of Congress Cataloging-in-Publication Data
The asymmetrical brain / edited by Kenneth Hugdahl and Richard J. Davidson.
p. ; cm.
Rev. ed. of: Brain asymmetry / edited by Richard J. Davidson and Kenneth Hugdahl.
c1995.
‘‘A Bradford book.’’
Includes bibliographical references and index.
ISBN 0-262-08309-4 (alk. paper)
1. Cerebral dominance. 2. Laterality. I. Hugdahl, Kenneth. II. Davidson, Richard J.
III. Brain asymmetry.
[DNLM: 1. Dominance, Cerebral. 2. Brain—physiology. 3. Laterality. WL 335 A8608
2003]
QP385.5 .B725 2003
612.8
0
2—dc21 2002025092
10987654321

Contents
Preface ix
I Animal Models/Basic Functions 1
1 Hemispheric Asymmetry in the Visual System of Birds 3
Onur Gu¨ntu¨rku¨n
2 A Hippocampal Theory of Cerebral Lateralization 37
Akaysha C. Tang
3 Stress and Coping: Asymmetry of Dopamine Efferents
within the Prefrontal Cortex 69
Craig W. Berridge, Rodrigo A. Espan˜a, and Thomas A. Stalnaker
4 The Nature and Determinants of Handedness 105
Alan A. Beaton
II Neuroimaging and Brain Stimulation Studies 159
5 Characterizing Functional Asymmetries with Brain
Mapping 161
Karl J. Friston
6 Anatomical Brain Asymmetries and Their Relevance for
Functional Asymmetries 187
Lutz Ja¨ncke and Helmuth Steinmetz

7 Transcranial Magnetic Stimulation Studies of Asymmetry of
Cognitive Functions in the Brain 231
Alvaro Pascual-Leone and Vincent Walsh
III Visual Laterality 259
8 Interaction between the Hemispheres and Its Implications
for the Processing Capacity of the Brain 261
Marie T. Banich
9 Asymmetries in Encoding Spatial Relations 303
Bruno Laeng, Christopher F. Chabris, and Stephen M. Kosslyn
10 Complexities of Interhemispheric Communication in
Sensorimotor Tasks Revealed by High-Density Event-
Related Potential Mapping 341
Clifford D. Saron, John J. Foxe, Charles E. Schroeder, and
Herbert G. Vaughan, Jr.
IV Auditory Laterality 409
11 Hemispheric Asymmetries in the Processing of Tonal
Stimuli 411
Robert J. Zatorre
12 Dichotic Listening in the Study of Auditory Laterality 441
Kenneth Hugdahl
13 Effects of Attention on Hemispheric Asymmetry 477
Daniel S. O’Leary
V Emotional Laterality 509
14 The Functional Neuroimaging of Human Emotion:
Asymmetric Contributions of Cortical and Subcortical
Circuitry 511
Diego Pizzagalli, Alexander J. Shackman, and Richard J.
Davidson
vi Contents

15 Regional Brain Activity in Anxiety and Depression,
Cognition/Emotion Interaction, and Emotion Regulation 533
Wendy Heller, Nancy S. Koven, and Gregory A. Miller
16 The State and Trait Nature of Frontal EEG Asymmetry in
Emotion 565
James A. Coan and John J. B. Allen
VI Neurological Disorders 617
17 Agenesis of the Corpus Callosum 619
Maryse Lassonde and Hannelore C. Sauerwein
18 Developmental Disorders: Dyslexia 651
Mark A. Eckert and Christiana M. Leonard
19 Structural Correlates of Brain Asymmetry: Studies in Left-
Handed and Dyslexic Individuals 681
Michel Habib and Fabrice Robichon
VII Psychiatric Disorders 717
20 Frontal and Parietotemporal Asymmetries in Depressive
Disorders: Behavioral, Electrophysiologic, and
Neuroimaging Findings 719
Gerard E. Bruder
21 The Laterality of Schizophrenia 743
Michael F. Green, Mark J. Sergi, and Robert S. Kern
Contributors 773
Author Index 777
Subject Index 793
vii Contents

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Preface
In April 1999, at the Cognitive Neuroscience Meeting in Washington,
D.C., MIT Press representative Michael Rutter asked one of us (KH) if
it was not about time to publish a second edition ofBrain Asymmetry,
which had been published by MIT Press in 1995. Had not the ﬁeld
progressed since 1995, so that it was now time for an update, or even
a new book based on the most recent research in the ﬁeld of brain
asymmetry? On his way home to Bergen, Norway, Kenneth Hugdahl
stopped over in Madison, Wisconsin, to meet with Richard Davidson,
the other editor of the ﬁrst book. Davidson agreed that indeed the ﬁeld
had progressed during the years since the ﬁrst volume; thus a new
volume could be an important update of the most recent ﬁndings in
the ﬁeld. That was the start of this volume, which is a completely new
book on brain asymmetry, with 21 original chapters.
In the preface to the 1995 volume we wrote, ‘‘We cannot identify any
other construct that forms the focus of such a diverse array of behav-
ioral processes. The study of brain asymmetry continues to attract
unique forms of integration in the biobehavioral sciences.’’ The mys-
teries of the two hemispheres of the brain, how they differ functionally
and structurally, how they communicate, and how they participate in
the cortical and subcortical circuitry underlying complex cognition and
affect still fascinate and interest young and old neuroscientists. What
we wrote in 1995 about the diverse array of behavioral processes being
reﬂected in the asymmetry construct is no less relevant today than it
was in 1995. To mention just one example, the development of new
neuroimaging techniques—functional magnetic resonance imaging
(fMRI), positron emission tomography (PET), and magnetoence-
paholograpy (MEG)—have revealed how neuronal activation is asym-

metrically organized and distributed across the hemispheres, providing
evidence for how the asymmetry construct becomes ever more reﬁned
and detailed. This topic was not included in the 1995 volume but has a
part of its own in the present volume. Another topic that has been the
focusofmuchrecentresearchistheuseofhigh-resolutionstructural
MR imaging to reveal subtle morphological differences between the
hemispheres. Thus, it has become possible to look for correspondences
of structural and functional asymmetries between the hemispheres.
Most of the interest has been in the upper posterior parts of the tem-
poral lobe and adjacent areas in the parietal lobe. Both the planum
temporale and the planum parietale, in the temporal and parietal lobes,
respectively, have attracted much interest, relating structural-functional
asymmetries in these areas to such diverse clinical syndromes as dys-
lexia and schizophrenia. This is covered in several chapters in the
present volume.
A goal of the present volume has been to show the international
interest in brain asymmetry and related concepts. We hope this is
reﬂected in the various contributions, with authors from the United
States, Canada, United Kingdom, Germany, France, and Norway.
Folk psychology statements like ‘‘The left hemisphere is specialized,
or dominant, for language, and the right hemisphere is specialized, or
dominant, for visuospatial functions, or space orientation’’ obviously
tell an incomplete, and sometimes inaccurate, story. First of all, such
statements imply that the brain basically is specialized only for two
functions, language and the ability to orient in the environment. Sec-
ond, they imply that half the brain does only language and the other
half does only visual processing. This also is obviously wrong. On the
contrary, a prevailing aspect of research throughout the history of brain
asymmetry is the notion that asymmetries exist at all levels of the ner-
vous system, including also the peripheral and autonomic nervous
systems. Another prevailing idea is that asymmetries exist not only
for higher cognitive processes, like language and visuospatial pro-
cessing, but also for emotional processes. A third aspect is that recent
advancesinmethodshavemadeitpossibletoquantifystructuralasym-
metries with much greater precision and resolution than was available
previously. This has resulted in new theories and models of how
functional asymmetries may have their structural correlates in brain
anatomy.Afourthaspectisthedevelopmentofthenewneuroimaging
techniques, both hemodynamic techniques (e.g., PET and fMRI) and
xPreface

other techniques (ERP [event-related potential], MEG, and transcranial
magnetic stimulation [TMS]). A ﬁfth aspect of recent asymmetry re-
search is its application to clinical areas with regard to psychiatric,
neurological, and developmental disorders. It is our intention to cover
all these ideas and developments as a reﬂection of the current status of
the ﬁeld, from both a basic research and a clinical perspective.
In selecting the contributors, it was our intention to focus on rela-
tively recent and new topics as well as a few older topics where there
have been new developments since 1995. Selecting the contributors
therefore meant, as always, that not all prominent researchers in the
ﬁeld could be invited. This would have made the volume unwieldy. We
have therefore chosen to present the ﬁeld through a mixed selection of
chapters ranging from basic physiological processes on the neuronal
level to major clinical disorders like schizophrenia and depression.
When inviting the selected authors, it was our intention to include
promising and novel ideas in the ﬁeld, with potential for possible
breakthroughs in the near future. For these reasons the book is divided
into seven major parts that include animal models of asymmetry and
basic asymmetrical functions (e.g., handedness), neuroimaging studies,
visual asymmetry, auditory asymmetry, emotional asymmetry, and
applications for neurological and psychiatric disorders. Each part
has two or more chapters that are intended to illustrate the range of
methods and research topics within each area that is represented.
In part I, on animal models and basic functions, Onur Gu¨ntu¨rku¨n
provides a review of studies on the lateralization of the visual system
in various species of birds, thus providing an animal model for the
understanding of the neuronal substrates of visual asymmetry. This is
followed by the chapter by Akaysha Tang, who presents a new theory
of asymmetry based on the role played by left and right nuclei com-
plexes in the hippocampus, taking a bottom-up approach to asymmetry
and laterality. In the third chapter, Craig Berridge and coworkers show
how stress and coping are related to the asymmetry of the dopamine
system within the prefrontal cortex. The ﬁnal chapter in part I, by Alan
Beaton, provides an updated and comprehensive review of handedness
effects in research on brain asymmetry.
Part II, which deals with brain imaging and brain stimulation, starts
with a chapter by Karl Friston on experimental design and statistical
analysis of functional brain imaging studies, focusing on issues related
to asymmetry and lateralization in functional brain architecture. Next,
xi Preface

Lutz Ja¨ncke and Helmut Steinmetz review their extensive research on
anatomical brain asymmetry, particularly research on the role of the
planum temporale area in the upper posterior temporal lobe. This is
followed by a chapter by Alvaro Pascual-Leone and Vincent Walsh on
the new transcranial magnetic stimulation (TMS) technique and what
this method will contribute to an enhanced understanding of the func-
tions of the cerebral hemispheres.
Part III is devoted to studies on visual asymmetry and laterality,
starting with the contribution by Marie Banich on hemispheric inter-
actions, and implications for theories of information processing and
processing capacity in the brain and in the left and right hemispheres.
Bruno Laeng and collaborators review studies on asymmetries in en-
coding of spatial relations, providing evidence for different kinds of
spatial encoding properties in the left and right hemispheres. Next,
Clifford Saron and coworkers present an extensive review of ERP work
with visual half-ﬁeld stimulus presentations, focusing on the complex-
ities of interhemispheric communication.
Part IV consists of three chapters, are devoted to auditory laterality.
Robert Zatorre reviews work related to hemispheric asymmetries in the
processing of tonal stimuli, including asymmetries for musical stimuli
and music. Kenneth Hugdahl presents an update on dichotic listen-
ing studies with speech sounds, including a new database containing
dichotic listening performances from more than 1000 subjects. Finally,
Daniel O’Leary shows the effects of attention on the asymmetry for
speech and nonspeech sounds, with applications to schizophrenia.
Part V, on emotional laterality, opens with a chapter by Diego Piz-
zagalli, Alexander J. Shackman, and Richard Davidson on how the two
hemispheres of the brain differ in their contributions to emotions and
emotional behavior, focusing on functional neuroimaging data. Next,
Wendy Heller and collaborators present a model of anxiety and emo-
tional functioning with a focus on the asymmetrical contributions of the
left and right hemispheres to the understanding of the neural imple-
mentation of emotions and emotional disorders. James Coan and John
Allen close the part with a comprehensive review of studies of frontal
EEG asymmetry as a measure of state and trait indices of positive and
negative emotions, and the interactions with the functioning of the left
and right cerebral hemispheres.
Part VI deals with studies of asymmetry in relation to neurological
disorders. Maryse Lassonde and Hannelore Sauerwein present their
xii Preface

work on patients with agenesis of the corpus callosum and implications
for understanding the nature of both specialization and integration of
the hemispheres. Next, Mark Eckert and Christiana Leonard review
data and theories of dyslexia, one of the most common developmental
disorders, and its neurobiological substrates from the perspective of
brain asymmetry. This is followed by a chapter by Michel Habib and
Fabrice Robichon, who also focus on the brain mechanisms of dyslexia,
presenting evidence for the importance of structures outside of those
brain regions traditionally believed to be important for the under-
standing of dyslexia.
In part VII, on psychiatric disorders, Gerard Bruder presents be-
havioral, electrophysiological, and hemodynamic brain imaging data
showing functional asymmetries in depression and depressive dis-
orders, and how this relates to, for example, clinical features. In the
ﬁnal chapter, Michael Green and coworkers present an overview of
theoretical models of and empirical evidence for a view of schizophre-
nia as being related to impaired asymmetry and laterality, and possibly
having neuroanatomical substrates as well.
It is our sincere hope that this volume will contribute to a continued
interest in one of the most fascinating aspects of the mammalian brain,
its division into left and right halves along the neuroaxis. We further
hope that it will contribute to better integration of the neurosciences,
with different subdisciplines—psychology, psychiatry, neurophysio-
logy, neurology, and neurosurgery, to mention a few examples—
working together to unravel the great mystery of the brain.
In addition to thanking the authors of the chapters, we would like to
acknowledge the contributions of several other people without whose
help and assistance this volume would not have been published. Our
thanks go ﬁrst to Mette Thomassen at the Department of Biological and
Medical Psychology, University of Bergen, Norway, for assisting in all
stages of the editorial process, and Hilde Gundersen for assistance with
the proofreading. Second, we would like to thank the staff at MIT Press,
who have helped and advised us throughout the editorial process.
xiii Preface

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I
Animal Models/Basic Functions

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1
Hemispheric Asymmetry in the Visual
System of Birds
Onur Gu¨ntu¨rku¨n
The quest for the biological foundations of functional cerebral asym-
metries has dominated lateralization research since the days of Broca
(1865). Meanwhile, several anatomical asymmetries correlating with
certain lateralized functions have been described in man. However, our
knowledge of the ontogenetic variables that shape these structural
asymmetries is still limited to an important extent (Previc, 1991). Like-
wise, we have few clues to how these asymmetries are translated into
the lateralized functioning of a whole brain. Animal models can pro-
vide a powerful tool to permit detailed insights into the neuronal pro-
cesses governing lateralized function. Avian visual lateralization is a
particularly useful model because it not only allows experimental in-
vestigation of the interplay of neurobiological substrate and behavioral
functions, but also provides an opportunity to study the ontogenetic
events leading to asymmetries. Therefore the main emphasis of the fol-
lowing account is threefold. First, the behavioral framework of visual
lateralization will be recapitulated in various species of birds. Then, the
neuronal substrate of visual asymmetry will be outlined. Finally, the
ontogentic scenario that ultimately results in a lateralized functional
architecture will be described. The picture emerging from this overview
will show that visual asymmetries in birds develop due to a tight inter-
play of genetic and epigenetic factors that ﬁnally, during a short critical
period, mold ascending visual pathways into a lateralized status. Once
the neuronal substrate is wired in this lateralized fashion, perceptual,
cognitive, and motor systems start to function asymmetrically for the
rest of the individual’s lifetime.

VISUAL LATERALIZATION IN BIRDS—A BEHAVIORAL ANALYSIS
Tasks Favoring the Left Hemisphere
Birds are the most visually dependent class of vertebrates, and the
statementofRochon-Duvigneaud(1943)thatapigeonisnothingbut
two eyes with wings is probably valid for most avian species. Man, a
highly visual primate, sees the world with the information transmitted
by about 1 million ﬁbers within each optic nerve. This is only 40% of
the number of retinal axons counted in a single optic nerve of pigeons
and chicks (Binggeli & Paule, 1969; Rager & Rager, 1978). The acuity of
manybirdsofpreysurpassesthatofotherlivingbeings(Foxetal.,
1976), and even the unspecialized pigeon excels relative to humans in
its ability to discriminate luminances (Hodos et al., 1985) and to discern
subtle color differences (Emmerton & Delius, 1980). However, the most
important advantage of the avian model for asymmetry research is not
its visual specialization, but the ease with which each hemisphere can
be tested virtually separately. The optic nerves in birds decussate nearly
completely, and only less than 0.1% of the ﬁbers proceed to the ipsi-
lateral side (Weidner et al., 1985). Since only limited numbers of axons
recross via mesencephalic and thalamic commissures, the avian visual
system is remarkably crossed.
This anatomical condition enables the use of eyecaps to study the
performance of the animals with sight restricted to one eye, and thus
mainly the contralateral hemisphere. With this procedure, visual lat-
eralization can be demonstrated using a wide range of techniques.
Using the right eye, adult pigeons are superior in discriminating
two-dimensional artiﬁcial patterns (Gu¨ntu¨rku¨n, 1985) and three-
dimensional natural objects (Gu¨ntu¨rku¨n & Kesch, 1987). These results
are very similar to experiments with zebra ﬁnches (Alonso, 1998) and
with chicks tested with the pebble-ﬂoor task. Here, young chicks peck
food grains from a background of small pebbles that are stuck to the
ﬂoor. The animals usually learn to discriminate food from pebbles
within 60 pecks. Under either left- or right-eye learning conditions,
their performance is higher with the right eye/left hemisphere (Hamb-
ley & Rogers, 1979; Mench & Andrew, 1986). In pigeons this greater
visual processing capacity of the right eye system in pattern discrimi-
nation also leads to a higher degree of illusion of this side when being
confronted with geometrical optic illusions (Gu¨ntu¨rku¨n, 1997b).
4OnurGu ¨ntu¨rku¨n

All experiments summarized up to now employed a positive and a
negative stimulus that had to be distinguished. A new aspect of avian
visual lateralization emerges if more than two stimuli are used to in-
duce a memory load. In a visual memory task pigeons learned under
binocular conditions to discriminate between 100 negative (SO)and625
positive (Sþ) artiﬁcial patterns. The stimuli had been randomly assigned
to these two categories (ﬁgure 1.1). After reaching criterion, the birds
were tested alternately with their left or right eye seeing. The pigeons
were able to remember most of the 725patterns with their right eye,
but were barely above chance level with their left (Fersen & Gu¨ntu¨r-
ku¨n, 1990). This experiment suggests that visual engrams learned dur-
ing training were stored, at least in part, unilaterally in the dominant
left hemisphere, although both eyes had equal access to the patterns
during acquisition.
Indeed, the existence of such unilateral memory stores with limited
access by the other hemisphere could be shown in another complex
task in which pigeons had to distinguish symmetric from asymmetric
patterns. In this study they faced two vertically arranged pecking keys
on which the same patterns were displayed. If these two identical pat-
terns were symmetric, the animals had to peck the lower key; if they
were asymmetric, the upper key was correct. Pigeons needed about ﬁve
months to learn this conjunction of stimulus class and location. Up to
that point they did not wear eyecaps. Then they were to proceed with
the left or the right eye open, alternately. This new condition revealed
that most animals had learned the task with their right eye/left hemi-
sphere. The other side was completely naive, and in some birds needed
an additional ﬁve months to catch up with the ‘‘knowing’’ hemisphere
(Gu¨ntu¨rku¨n, 1997a). This experiment is a very dramatic demonstration
of unilaterality of engrams.
Such unilateral storage is not restricted to pigeons but has also been
demonstrated, albeit for shorter time spans, with chicks (Gaston & Gas-
ton, 1984), macaques (Doty et al., 1973), and even humans (Risse &
Gazzaniga, 1978). Thus, it is likely that the avian left hemisphere stores
large amounts of acquired pattern information to which the right hemi-
sphere has only limited access.
It is probably this asymmetry in memorizing visual stimuli that
results in a signiﬁcant right eye advantage when homing from a distant
release site over known territory to the loft (Ulrich et al., 1999). Homing
makes great demands on spatial orientation. To ﬁnd a left hemisphere
5Avian Visual Asymmetry

Figure 1.1Setup and some of the stimuli used in the study of Fersen and Gu¨ntu¨rku¨n
(1990). Two out of 725stimuli (100 positive [Sþ], 625negative [SI]) were backprojected
onto the vertical pecking keys with Sþand SIrandomly changing between left and right.
(Adapted from Fersen & Gu¨ntu¨rku¨n, 1990.)
6OnurGu ¨ntu¨rku¨n

advantage during homing is therefore astonishing, considering the
large body of data showing a right hemisphere dominance for visuo-
spatial tasks. However, spatial orientation is a multicomponent feature
in which several cognitive processes with diverse cerebral asymmetries
interact (Hellige, 1995). It is therefore conceivable that the pigeons used
a cognitive strategy that is more left-hemisphere based. As discussed
by Ulrich et al. (1999), it is likely that the birds utilized visual memory-
based snapshot tracking to pursue visual features along their pre-
learned route. Due to their left-hemisphere dominance for memorizing
and discriminating visual features, the homing task was therefore prob-
ably performed by a succession of visual feature discriminations. If
pigeons are tested in a maze where they cannot utilize this strategy, the
left hemisphere advantage vanishes (Prior & Gu¨ntu¨rku¨n, 2001).
Visual lateralization also affects cognitive processes of the animals.
Diekamp et al. (1999) tested pigeons under monocular conditions in
successive color reversals. The animals learned to favor green (Sþ)over
red (SO) until reaching learning criterion. Then the conditions were
changed; red was now rewarded (Sþ) and green was not (SO). As soon
as the pigeons successfully learned the reversal, conditions were altered
again, and so on. One group of animals performed 30 reversals under
right-eye-seeing, and the other group under left-eye-seeing, conditions.
After a couple of reversals both groups showed a ‘‘learning-to-learn’’
effect such that each reversal was achieved with fewer trials. Reversal
learning can be described best on a mathematical basis by an exponen-
tial function of the typey¼aþexp
ðbOcxÞ
witharepresenting the asymp-
tote (i.e., the error rate around which the performance oscillates after
several reversals),bdetermining the starting value of the function for
the ﬁrst reversal, andcrepresenting the steepness of the curve (i.e., the
rate of error reduction over successive reversals). For bothaandc,
Diekamp et al. (1999) could reveal a right eye superiority. Thus, using
the right eye/left hemisphere, the animals were faster in understanding
the basic principle of this experiment (c) and exhibited a higher level of
performance after reaching asymptote (a). Visual lateralization in birds,
therefore, not only consists of asymmetries in simple pattern recogni-
tion and memorization processes, but also affects ‘‘cognitive’’ systems
that extract general properties of the visual world.
The behavioral asymmetry summarized in these studies is very likely
not due to simple psychophysical differences between the eyes (but
see Hart et al., 2000, in starlings), but involves differences in ‘‘higher’’
functions that affect hemisphere-speciﬁc performances in cognitively
7 Avian Visual Asymmetry

demanding tasks. This conclusion is supported by studies showing
no left-right differences in purely psychophysical tasks: There are no
asymmetries in acuity (Gu¨ntu¨rku¨n & Hahmann, 1994), in depth reso-
lution (Martinoya et al., 1988), or in wavelength discrimination (Remy
& Emmerton, 1991). That visual lateralization is generated by central
mechanisms is additionally shown by experiments revealing asymmet-
rical effects of unilateral lesions or pharmaceutical insults of the left or
the right hemisphere (Howard et al., 1980; Gu¨ntu¨rku¨n&Hoferichter,
1985; Gu¨ntu¨rku¨n & Hahmann, 1999; Deng & Rogers, 1998a).
Interim SummaryWhen distinct features of visual objects have to be
identiﬁed, memorized, and/or categorized, a right eye/left hemisphere
dominance arises in all avian species studied up to now (Andrew,
1991). This right eye superiority is valid for the majority of individuals
of a population (65–79%, Gu¨ntu¨rku¨n, 1997b; Gu¨ntu¨rku¨n et al., 2000),
indicating a clear population asymmetry.
Tasks Favoring the Right Hemisphere
None of the avian hemispheres completely dominates visual analysis,
but cerebral asymmetries are organized in complementary specializa-
tions for different kinds of stimuli within the visual scenery. If birds
have to encode spatial conﬁgurations, a left eye/right hemisphere su-
periority can be demonstrated (but see the discussion above for homing
data from Ulrich et al., 1999). This was clearly shown by Rashid and
Andrew (1989). They trained chicks to ﬁnd food buried under sawdust
in an arena. When the chicks were tested monocularly without food,
birds under monocular left conditions searched from posthatch day 9
onward in the two areas speciﬁed by cues, while chicks in the monoc-
ular right condition searched randomly over the complete arena.
The lateralized role of different spatial and nonspatial cues can be
beautifully studied in food-storing birds during cache localization.
Marsh tits store food in large numbers of caches scattered over the
home range that they can retrieve many days later with astounding
accuracy (Shettleworth, 1990). It is possible to study lateralization of
food storing and cache retrieval under controlled conditions, using a
room with artiﬁcial trees, perches, and small holes for caching. In one
of these studies (Clayton & Krebs, 1994) four feeders were used that
were distinguishable by their speciﬁc location and by markings that
8OnurGu ¨ntu¨rku¨n

made them visually unique. Under monocular conditions birds were
given parts of a nut in one out of four feeders and were then removed
for 5min. During this interval the location of the correct feeder was
swapped with an empty one so that spatial and object cues could be
dissociated. Then the animals reentered and were allowed to retrieve
the rest of the nut with the same eyecap condition. With the left eye,
marsh tits looked for the seed at the correct spatial location, while they
relied on object-speciﬁc cues when using the right eye. Thus, the right
hemisphere used spatial cues, while the left half of the brain utilized
object cues to locate the nut.
Vallortigara and colleagues were able to design a variety of inge-
nious tasks that demonstrate a similar pattern of results in chicks. In
one of these experiments (Vallortigara, 2000; Tommasi & Vallortigara,
2001), chicks were trained to ﬁnd food under sawdust by scratching
ground in the center of a square arena. The position of the food was
indicated by its geometric position (arena center) and by a conspicuous
landmark, which also was placed centrally (ﬁgure 1.2). After learning
attainment, the landmark was displaced to a novel position so as to
generate conﬂicting local (the landmark) and global (the center of the
arena) information. Chicks viewing with their left eye (right hemi-
sphere) still searched in the center, completely ignoring the new loca-
tion of the landmark. Right-eye chicks (left hemisphere) did exactly the
opposite, searching close to the landmark and ignoring the global spa-
tial information provided by the environment. Binocular-seeing chicks
were mainly relying on right hemisphere mechanisms and scratched in
the arena’s center. Thus, different species of birds utilize left hemisphere
mechanisms if relying on object cues and right hemisphere functions if
using spatial cues. Chicks also scrutinize the stimuli mainly with their
right eye when object-speciﬁc cues are to be used, but look mainly with
their left eye when spatial cues have to utilized (Vallortigara et al.,
1996).
Besides spatial tasks, visually guided social recognition also seems
to be a domain of the right hemisphere. If chicks have to choose in a
runway between a cagemate and an unfamiliar chick, male animals
decide for the stranger, while females take the cagemate (Vallortigara
& Andrew, 1994). Under monocular conditions these sex-dependent
choice patterns persist when using the left eye, whereas the animals
behave at random when using the right (Vallortigara, 1992). This has
also been shown with the social pecking test, which takes advantage of
9 Avian Visual Asymmetry

the marked xenophobia exhibited by young socially reared chicks to-
ward unfamiliar conspeciﬁcs, which become the target of aggressive
pecking bouts. If young chicks wearing eyecaps are confronted with
both a familar and an unfamiliar bird, they mainly peck the stranger
when viewing with the left eye, while their aggressive encounters
against the other two animals are random under monocular right con-
ditions (Vallortigara, 1992). These data indicate that right hemisphere
processes are of prime importance for social recognition. Up to now
this has been demonstrated only in preference tests where it is up to the
animal to behave in a certain way. Whether the results of these prefer-
ence tests will reveal the same data pattern as in forced discrimination
studiesispresentlyanopenquestion.
Interim SummaryWhen birds have to locate food in a complex envi-
ronment, they rely on object-speciﬁc cues when seeing with the right
eye and on geometric information when seeing with the left. In prefer-
Figure 1.2Search behavior of chicks trained to ﬁnd food in the center of a square arena
next to a conspicuous object. The upper left picture depicts areas of searching intensity
under binocular conditions after initial training. The darker the areas, the more often the
chicks searched under sawdust. The other three pictures show the results after displace-
ment of the landmark to a novel position, inducing a conﬂict between geometry-based
and object-based spatial codings. After landmark displacement, chicks were tested under
binocular, left-eye, and right-eye seeing conditions. Right and left hemispheres seem
to code for geometry- and object-speciﬁc cues, respectively. (Adapted from Vallortigara,
2000.)
10 Onur Gu ¨ntu¨rku¨n

ence tests it can be shown that visually guided social recognition also
seems to be a right hemisphere domain. However, it is at present
unclear how the pattern of right hemisphere dominances for social rec-
ognition and the previously reviewed data on a left hemisphere supe-
riority in visual feature categorization can be matched, since a social
companion ﬁrst has to be recognized as a visual object, which is a typ-
ical left hemisphere task. It is conceivable that social cues are rich in
emotional (Vallortigara & Andrew, 1994) or movement information,
and thus may be treated differently from static visual cues (Dittrich &
Lea, 1993).
ANATOMICAL SUBSTRATES FOR VISUAL LATERALIZATION
In birds, retinal information to the forebrain is processed by two
parallel pathways: the tectofugal system and the thalamofugal sys-
tem, suggested to be equivalent to the extrageniculo-cortical and the
geniculo-cortical visual pathways of mammals, respectively (Shimizu &
Karten, 1993). The avian tectofugal pathway is composed of optic nerve
ﬁbers projecting to the contralateral optic tectum, from which ﬁbers
lead bilaterally to the thalamic n. rotundus (Rt) and n. triangularis (T),
which themselves project to the ipsilateral ectostriatum (E) of the fore-
brain (ﬁgure 1.3). The thalamofugal pathway projects from the retina
via the contralateral n. geniculatus lateralis, pars dorsalis (GLd) bilat-
erally to the visual Wulst in the telencephalon (see ﬁgure 1.5) (Gu¨n-
tu¨rku¨n, 2000). The tectofugal and thalamofugal pathways have been
shown to constitute structural asymmetries related to lateralized visual
behavior in pigeons and chicks, respectively.
The Tectofugal Pathway
In the asymmetry experiments with pigeons, the stimuli fell into the
frontal binocular visual ﬁeld of the animals. Since this portion of the
visual ﬁeld is mainly represented within the tectofugal pathway in pi-
geons (Hellmann & Gu¨ntu¨rku¨n, 1999; Gu¨ntu¨rku¨n & Hahmann, 1999), it
is conceivable that it is mainly the tectofugal system which generates
visual lateralization in this species (ﬁgure 1.3).
About 90% of all retinal ganglion cells project to the tectum in pigeons
(Remy & Gu¨ntu¨rku¨n, 1991). The optic tectum is a highly complex
neural entity in which even simple histological techniques visualize
11 Avian Visual Asymmetry

Figure 1.3Schematic view of the tectofugal visual pathway as seen in frontal sections.
Letters within the ﬁgure indicate areas or connections for which asymmetries were de-
scribed. (a) Morphological asymmetries of neuronal somata in different tectal layers.
Layer1isnotshownbecauseitconsistsofﬁbers.Leftorrightskewsofhistogramsdepict
larger somata on the left or right tectal side for this layer, respectively. Note consistent left
skewsinlayers2–12,whicharemostlyvisual.(BasedonGu ¨ntu¨rku¨n, 1997c.) (b)Average
soma size of rotundal neurons on the left or the right side. (Based on Manns & Gu¨ntu¨r-
ku¨n, 1999b.) (c) Bilaterality of rotundal afferents from the ipsilateral and the contralateral
tectum. An index of 0 decribes absolute symmetry, while 1 constitutes a system that is
characterized by ipsilateral afferents only. The signiﬁcant difference in the bilaterality in-
dex points to a larger proportion of contralateral tectal afferents in the left rotundus.
(Based on Gu¨ntu¨rku¨n et al., 1998.) (d) Asymmetries of tectotectal modulation. Electrical
stimulation of the right tectum was unable to substantially modulate the amplitude of
a visual evoked potential recorded within the left tectum (right-to-left modulation), re-
gardless of different interstimulus intervals (ISI). However, electrical stimulation of the
visually dominant left tectum resulted in much higher modulations of visually evoked
potentials within the right tectum (left-to-right modulation). (Based on Keysers et al.,
2000.)
12 Onur Gu ¨ntu¨rku¨n

15laminae (Ramo´n y Cajal, 1911). In pigeons, a morphometric study of
tectal perikarya sizes revealed morphological asymmetries with the
superﬁcially located retinorecipient cells being larger on the left side,
contralateral to the dominant eye (Gu¨ntu¨rku¨n, 1997c). This is also the
case for the n. rotundus, the next tectofugal entity (Manns & Gu¨ntu¨r-
ku¨n, 1999b). Thus, the pigeon’s tectofugal system displays signiﬁcant
morphological asymmetries that might be related to the behavioral lat-
eralization of the animals.
Tectal lamina 13 neurons project bilaterally onto the n. rotundus
(Hellmann & Gu¨ntu¨rku¨n, 1999). The bilaterality of this projection should
lead to representations of both the ipsi- and the contralateral eye in the
tectofugal system of each hemisphere. Indeed, Engelage and Bischof
(1993) were able to show that binocular input is represented in the
ectostriatum. In pigeons, Gu¨ntu¨rku¨n et al. (1998) demonstrated with
anterograde and retrograde tracers that the ratio of ipsi- to contralateral
tectorotundal projections is asymmetrically composed. While the num-
ber of ipsilateral tectorotundal projections is about equal, the number
of neurons projecting contralaterally from the right tectum to the left
rotundus is about twice the number in the opposite direction (Gu¨ntu¨r-
ku¨n et al., 1998). As a result, the n. rotundus on the left side receives,
beside a massive ipsilateral tectal input, a large number of afferents
from the contralateral tectum. Consequently, the visual input of the n.
rotundus that projects to the left hemisphere is bilaterally organized to
a signiﬁcantly higher degree than its counterpart in the right halfbrain.
Functionally, this anatomical condition could enable the left rotundus
to integrate and process visual inputs from both eyes, and thus from
both sides of the bird’s visual world. Indeed, a study has shown that
left rotundal processes are signiﬁcantly related to acuity performance
with the right and the left eye, whereas right rotundus participates only
in binocular acuity (Gu¨ntu¨rku¨n & Hahmann, 1999).
These data on the tectofugal system suggest that visual asymmetry is
anatomically wired, and thus probably ‘‘static’’ and unmodiﬁable over
the lifetime. However, several lines of evidence suggest this assump-
tion is incomplete. If the tectal and the posterior commissures, which
connect the tecta of both hemispheres, are transsected, visual laterali-
zation reverses to a left eye dominance; this laterality reversal is pro-
portional to the number of transsected ﬁbers (Gu¨ntu¨rku¨n&Bo¨hringer,
1987) (ﬁgure 1.4). If hemispheric asymmetry is reversed by tectal com-
missurotomy, it is likely that this asymmetry was maintained pre-
13 Avian Visual Asymmetry

viously, at least partly, by asymmetrical interactions between the tecta
(see also Parsons & Rogers, 1993) that are known to be primarily in-
hibitory (Robert & Cue´nod, 1969; Hardy et al., 1984). Keysers et al.
(2000) tested this hypothesis by recording ﬁeld potentials from left or
right intratectal electrodes in response to a stroboscope ﬂash to the
contralateral eye and an electrical stimulation of the contralateral tec-
tum. They found that the left tectum was able to modulate the ﬂash-
evoked potential of the right tectum to a larger extent than vice versa.
This lateralized interhemispheric cross talk thus could constitute an
important ‘‘dynamic’’ component of asymmetric visual processing (ﬁg-
ure 1.3).
This result makes it likely that the emergence of visual asymmetry in
pigeons is related to a dual coding of left-right differences. Thus, visual
lateralization cannot be explained entirely by the anatomical differences
Figure 1.4Lateralization reversal after tectal commissurotomy in pigeons. Pigeons per-
formed a pattern discrimination with right eye or left eye seeing. Preoperatively, sig-
niﬁcantly more pecks on the correct pattern were made with the right eye seeing; this
lateralization changed after commissurotomy. The inset shows that the degree of asym-
metry change, as expressed with an index, was signiﬁcantly related to the extent of the
commissurotomy. (Based on Gu¨ntu¨rku¨n&Bo¨hringer, 1987.)
14 Onur Gu ¨ntu¨rku¨n

between left and right components of the tectofugal pathway. Obvi-
ously a second, more dynamic component exists that is able to modu-
late neural processes of the optic tecta in an asymmetrical manner.
Altering this second dynamic component, as in the commissurotomy
experiment of Gu¨ntu¨rku¨nandBo¨hringer (1987), results in an important
alteration of visual asymmetry.
Interim SummaryThe pigeon’s tectofugal pathway displays numer-
ous morphological asymmetries that are probably related to the visual
lateralization at the behavioral level. On the left side of the brain, which
dominates object recognition mechanisms, soma sizes of most visual
cells are larger. In addition, the left n. rotundus integrates input from
both eyes to a greater extent than the right rotundus. In addition
to these structural left-right differences, the tecta inhibit each other
differently, with the left tectum modulating visual processes of the
contralateral side to a greater degree than vice versa. Thus, visual
asymmetry within the tectofugal pathway is dually coded by structural
and by dynamic properties.
The Thalamofugal Pathway
At ﬁrst glance the general organization of the thalamofugal pathway
seems to be similar in pigeons and chicks. However, in contrast to pi-
geons (Hodos et al., 1984), thalamofugal lesions affect frontal viewing
in chicks importantly (Deng & Rogers, 1997). This suggests that, unlike
pigeons, the frontal ﬁeld is represented within the thalamofugal system
in chicks. But this is not the only difference between chicks and pigeons.
As will be outlined below, the organization of tecto- and thalamofugal
pathways also seems to be different with respect to asymmetry in chicks
and pigeons.
With unilateral injections of retrograde tracers into the Wulst label
cells in the GLd of both sides (ﬁgure 1.5), the ratio of contralaterally to
ipsilaterally labeled GLd neurons is higher after right-sided than after
left-sided Wulst injections in 2-day-old chicks (Rogers & Sink, 1988). As
shown by Rogers and Deng (1998), this lateralized ratio difference is
due to a higher number of ﬁbers from the left thalamus to the con-
tralateral right forebrain than vice versa. The asymmetry of the crossed
thalamotelencephalic projection is pronounced in young males but dis-
appears at about three weeks of age, consistent with the behavioral
15Avian Visual Asymmetry

data on lateralized performance in the pebble-ﬂoor task (Adret & Rog-
ers, 1989; Rogers, 1996). The asymmetry of the contralateral thalamo-
fugal projections of female chicks is lower, but present and in the same
direction as in males (Rajendra & Rogers, 1993). This sex difference in
thedegreeofthisconnectionalasymmetrycouldbeanexplanationfor
the gender difference in lateralized performance, which is more pro-
nounced in male chicks (Zappia & Rogers, 1987).
The sex difference in visual asymmetry of chicks indicates a role of
steroids.Indeed,injectionsof17b-estradiol (E
2) in unhatched male em-
bryos increases the number of forebrain-projecting GLd neurons and
thus abolishes thalamofugal asymmetry, probably due to a ceiling ef-
fect (Rogers & Rajendra, 1993). Thus, the reduced behavioral asymme-
Figure 1.5Schematic view of the chick’s thalamofugal visual pathway in frontal sec-
tions. The crossed projections from the left nucleus geniculatus lateralis pars dorsalis
(GLd) to the right Wulst are more numerous than vice versa. The upper right histogram
shows that the ratio of contralateral to ipsilateral ﬁbers (c/i ratio) is signiﬁcantly higher in
the right Wulst. The lower right histograms depict that this asymmetry is mainly due to
the number of contralateral afferents to the Wulst. (Based on Rogers & Deng, 1999.)
16 Onur Gu ¨ntu¨rku¨n

try in females (Zappia & Rogers, 1987) might be due to their higher
levels of circulating estradiol during a sensitive period and the subse-
quent increase in the number of GLd relay cells, which overshadow the
projectional asymmetry observed in males. Injection of testosterone also
reduces structural asymmetry in the thalamofugal projection in females
and even reverses the thalamofugal asymmetry of males (Schwarz &
Rogers, 1992). The reversal in male chicks is accompanied by a reversal
of eye dominance in visual discrimination (Zappia & Rogers, 1987).
Thus, the development of visual lateralization in chicks is fundamen-
tally inﬂuenced by circulating sex steroids.
Interim SummaryThe thalamofugal pathway of chicks was shown to
be asymmetrically organized with respect to the contralaterally ascend-
ing thalamotelencephalic components. Changes in the degree of this
asymmetry correlate with alterations of visual lateralization. This pat-
tern is sex-dependent, with males having more pronounced left-right
differences.
Species Differences in Asymmetrical Organization of Visual
Pathways
Since visual lateralization in pigeons and chicks is similar at the be-
havioral level, a comparable organization of their neural asymmetries
would be expected. Studies, however, have shown this not to be the
case. While the thalamofugal pathway of pigeons is ‘‘frontally blind’’
(Remy & Gu¨ntu¨rku¨n, 1991), there is strong evidence in chicks that this
pathway receives input from the frontal visual ﬁeld (Wilson, 1980;
Deng & Rogers, 1997). Therefore, at the level of the retinothalamic pro-
jections, the thalamofugal system already seems to be organized differ-
ently in these two species.
A further point of divergence is the asymmetrical projections within
the thalamo- and the tectofugal systems. In pigeons, the number of
projections from the right tectum to the left rotundus is larger than
from the left tectum to the right rotundus (Gu¨ntu¨rku¨n et al., 1998). This
condition creates a higher degree of bilateral representation in the left
tectofugal pathway, which is functionally dominant for object discrim-
inations (Gu¨ntu¨rku¨n & Hahmann, 1999). The case is different with
chicks, in which no asymmetry can be found in the overall tectorotundal
projections (Deng & Rogers, 1998b; Rogers & Deng, 1999). Thus, the
17 Avian Visual Asymmetry

organization of the tectofugal pathway differs markedly in chicks and
pigeons.
The same applies to the thalamofugal pathway. While in chicks there
is a signiﬁcantly higher number of contralateral ﬁbers from the left GLd
to the right Wulst (Rogers & Deng, 1999), a comparable asymmetry is
absent in pigeons (Hellmann et al., in preparation). These species dif-
ferences in asymmetry are accompanied by differences in the detailed
composition of ascending projections: In pigeons the crossed projection
from the GLd onto the contralateral Wulst is constituted by a large
number of bilaterally projecting neurons (Miceli et al., 1990). In chicks,
however, ipsi- and contralaterally projecting GLD cells come from dif-
ferent neuronal populations (Deng & Rogers, 1998a). In addition, the
asymmetry of the thalamofugal system is sex-different in chicks (Rogers
& Rajendra, 1993), while in pigeons there is, at least at the behavioral
level, no evidence for a sex dependency of visual asymmetry (Gu¨ntu¨r-
ku¨n & Kischkel, 1992).
These differences between chicks and pigeons could reﬂect a simple
species effect in the anatomy of the ascending systems. However, it
is also possible that they result from age differences, since the data have
been collected from adult pigeons and young chicks. In fact, age is
known to affect the thalamofugal projections, with GLd-Wulst asym-
metries disappearing by the time the animals are three weeks old
(Rogers & Sink, 1988). Therefore, the species effect might arise due to
the differences between the developmental speed of chicks and pigeons.
Chicks are precocial animals that are active directly after hatch. Conse-
quently, both visual systems seem to be functional at hatch in chicks
(Mey & Thanos, 1992). This is remarkably different in the altricial pi-
geon, where the embryonic visual pathways are far less functional.
There is evidence that retinotectal projections become functional shortly
before hatch (Manns & Gu¨ntu¨rku¨n, 1997), but the animals hatch with
their lids closed and are initially unable to perform complex visuomo-
tor behaviors. Up to now any information on the maturation of the
thalamofugal system is lacking in pigeons. Since prehatch light input is
of decisive importance for the maturation of the ascending visual path-
ways (see below), it is conceivable that the species differences between
chicks and pigeons are triggered by their different maturational speed.
Interim Summary Although seemingly similar, visual lateralization
in chicks and pigeons is generated by different visual systems. In both
18 Onur Gu ¨ntu¨rku¨n

animals the contralateral components of the ascending projections are
asymmetrically organized, with the thalamofugal and the tectofugal
systems being the critical pathways in chicks and pigeons, respectively.
These differences in neuronal wiring might be due to the matura-
tional speed being slower in pigeons than in chicks. This could generate
species-speciﬁc differences of the ontogenetic conditions that affect the
developing visual systems of chicks and pigeons.
Asymmetries of Associative Forebrain Structures: Imprinting
The important role of left hemispheric forebrain structures becomes es-
pecially evident when using stimuli for which chicks have a predispo-
sition, as in imprinting studies. When young chicks are exposed to a
visually conspicuous object, they approach it, learn its characteristics,
and form a social attachment to it. In natural conditions the object is
usually the hen, but it need not to be; a wide range of objects will do,
though some are more effective than others. Given a choice between a
stimulus to which it was exposed and a different object, a chick will
prefer the training stimulus and will actively avoid the other one.
Evidence from autoradiographic and lesion studies suggests that the
intermediate part of the hyperstriatum ventrale (IMHV), an associative
forebrain structure, is part of a memory system in which the represen-
tation of the imprinting stimulus is at least partly stored (Horn, 1991).
The IMHV partly overlaps with the more ventrally located medioros-
tral neostriatum/hyperstriatum ventrale (MNH), which is especially
involved in processing auditory imprinting stimuli (Bredenko¨tter &
Braun, 2000). Neurons in the left and right IMHV are active during
imprinting learning, as judged by the number of neurons expressing
Fos-like immunoreactivity about 1 h after the end of training, and ex-
pression of this protein increases with the strength of learning (McCabe
& Horn, 1994). At about 60 min after imprinting, however, the changes
that can be detected in the right IMHV diverge from those in the left.
The protein kinase C mediated phosphorylation of proteins that have
the capacity to contribute to synaptic plasticity increases in left IMHV
(Meberg et al., 1996). Consequently, strongly imprinted animals de-
velop, on the average, 10% larger postsynaptic densities in the left
IMHV than in the right, with the values of the right IMHV not being
different from controls (Bradley et al., 1981). The amount of binding
to NMDA receptors in the left, but not in the right, IMHV correlates
19 Avian Visual Asymmetry

signiﬁcantly with the behavioral preference scores of the chicks for the
imprinting stimulus (McCabe et al., 1982). Since morphological changes
are a prerequisite for long-term synaptic plasticity, Solomonia et al.
(1997, 1998) studied clathrin proteins and neural cell adhesion mole-
cules (N-CAMs), which are both involved in synaptic remodeling. They
found higher amounts of clathrin and N-CAM in the left IMHV 24 h
after learning, with both clathrin and N-CAM amounts correlating with
learning strength of imprinting.
Bilateral IMHV lesions impair imprinting but have no effect on visual
associative learning in general (Johnson & Horn, 1986). These lesions
also impair sexual imprinting, so that lesioned adult females no longer
show clear preferences for males that are selected by control females
(Bolhuis et al., 1989). The neurobiological differences between left and
right IMHV suggests that the two hemispheres participate differently
in the imprinting process. Indeed, studies in which the IMHV of the
left and the right side were lesioned sequentially support this assump-
tion. These experiments suggest that the left IMHV is important for the
ﬁrst acquisition and also can act as long-term store. The right IMHV
acts as a buffer store, passing information out to further, probably dis-
tributed, long-term stores over a period of about 6 h (Horn & Johnson,
1989). Due to this sequence of processes, a chick that receives a left
IMHV lesion 3 h after imprinting, followed 26 h later by lesioning of
the right IMHV, can recall the memory on retest because in this case
the engram could successfully be transferred to structures outside the
IMHV (Cipolla-Neto et al., 1982).
Thus, both IMHVs contribute to imprinting (Johnston & Rogers, 1998),
albeit with functional differences. These differences are reﬂected in the
single unit properties of left and right IMHV neurons. About 30% of
cells within this structure respond highly selectively to the familiar
imprinting object, irrespective of left or right (Brown & Horn, 1994;
Nicol et al., 1995). The difference between the hemispheres seems not to
be related to the training stimulus but to the stimuli that werenotused
for imprinting training. While for the left IMHV, training results in an
increase of cells responding to the training stimulus without affecting
responses to the other stimuli (Brown & Horn, 1994), the same increase
occurs in the right IMHV, but is associated with a decrease in sites
responding to the alternative stimuli (Nicol et al., 1995). These alter-
ations should result in an overall higher signal-to-noise ratio in the
20 Onur Gu ¨ntu¨rku¨n

right IMHV. Taking these single unit data into account, Nicol et al.
(1995) assume that the lack of ultrastructural and molecular changes
observed in the right IMHV after imprinting is not due to an absence of
changes, but to the presence of two contrary events, one increasing syn-
aptic efﬁciency for the trained stimulus, and one decreasing efﬁciency
for the untrained stimulus. Obviously the simpler changes in the left
IMHV sufﬁce for recognition in the context of imprinting tests of ani-
mals with right IMHV lesions. However, these chicks are unable to
utilize the training stimulus as an Sþin subsequent visual discrimi-
nation tasks (Honey et al., 1995). Only chicks with an elaborate repre-
sentation in different forebrain areas manage this transfer, and the
differentiated alterations in right IMHV synaptic structure seem to be
a prerequisite for the formation of a distributed memory store with
widespread effects for the adult animal.
Interim SummaryYoungchicksveryquicklyformanattachmentto
a conspicuous object. This imprinting learning requires the forebrain
IMHV to be intact. Left and right IMHV contribute differently to this
learning process. While the left IMHV seems to be essential during ini-
tial learning, the right IMHV is essential to induce processes that sub-
sequently stabilize and elaborate the imprinting engram.
Asymmetries of Associative Forebrain Structures: One-Trial
Avoidance Learning
Young chicks peck spontaneously at small, conspicuous objects, and
thus learn to discriminate between unpleasant and tasty items. If they
are confronted with a small, bright bead coated with the bitter-tasting
substance methylanthranilate (MeA), their pecking behavior is fol-
lowed by an intense disgust response. Subsequent tests with the same
bead lead to avoidance. This highly discrete passive avoidance learn-
ing (PAL) is accompanied by a number of lateralized events in the
forebrain.
If chicks acquire PAL under binocular conditions with a bead of a
certain color and are subsequently tested monocularly, they avoid all
beads, irrespective of their color, with the left eye, but are selective for
the color used during training with their right eye (Andrew, 1988).
Thus, it is conceivable that the more speciﬁc memory trace has been
21 Avian Visual Asymmetry

laid down in the left hemisphere. This assumption is supported by 2-
[
14
C] deoxyglucose (2-DG) experiments which demonstrate that 2-DG
injected shortly before training leads to higher radioactivity scores in
the left IMHV and the left lobus parolfactorius (LPO) (Rose & Csillag,
1985). The early phase of memory consolidation involves a cascade of
synaptic events that seem to hold the trace brieﬂy and simultaneously
initiate the gene activation processes required for long-term memory
(Rose, 1995). In brief, these steps ﬁrst require an increased glutamate
receptor binding in the left, but not the right, IMHV (Stewart et al.,
1992); a concomitant upregulation of NMDA (Steele et al., 1995); then a
pre- and postsynaptic Ca
2þ
ﬂux (Salinska et al., 1999). The increased
opening of Ca
2þ
channels, combined with further molecular events,
leads to an activation of the immediate early genes c-fos and c-jun
(Anokhin & Rose, 1991), which probably initiate pre- and postsynaptic
structure alterations.
These asymmetric morphological alterations are generally more pro-
nounced in the left IMHV and have been analyzed at the ultrastructural
level. Some of these lateralized changes show up within the ﬁrst hour
after PAL: the number of synapses per volume neuropil are signiﬁ-
cantly larger in the left but not in the right IMHV after training; simi-
larly, posttraining vesicles per synapse are about 60% more numerous
in the left IMHV (Stewart et al., 1984). Some other asymmetries exist
before training, but are subsequently abolished or even reversed: The
number of synaptic vesicles per volume neuropil are larger on the right
in control animals, while this asymmetry is reversed after PAL (Stewart
et al., 1984). These synaptic changes are accompanied by a reversal in
the number of dendritic spines on large multipolar projection neurons.
These were found to be more numerous in the right IMHV of unlearned
animals, but subsequent to training there was an increase in number on
the left such that this hemispheric asymmetry disappeared (Patel et al.,
1988a, b).
Morphological changes after PAL are not restricted to the IMHV,
but are also observed in the LPO and the paleostriatum augmentatum
(PA), two structures that correspond to the dorsal corpus striatum of
mammals. While the initial acquisition of memory involved largely
transient changes in the spatial organization of synapses in the left
IMHV, longer-term changes are more prominent in the LPO and in-
volve a bilateral, albeit predominantly left-sided, increase in synaptic
density and height (Stewart & Rusakov, 1995; Rose & Stewart, 1999).
22 Onur Gu ¨ntu¨rku¨n

Lesion studies demonstrated asymmetric effects of unilateral IMHV
and LPO lesions, and in addition support a model in which the mem-
ory trace after training is not ﬁxed to a certain area but ‘‘ﬂows’’ from
one structure to the other (Rose, 1991; ﬁgure 1.6). The presence of an
intact left IMHV seems to be a necessity for a long-term acquisition of
PAL, and consequently pretraining lesions of this area make the ani-
mals amnesic shortly after the learning session. However, if the animals
have learned the task and the left IMHV is lesioned 1 h after training,
the chick is not amnesic (Patterson et al., 1990). The engram seems to
have left the IMHV of the left hemisphere for yet another store, and it is
likely that this second store is the right IMHV, followed, within about
an hour, by the third store, which is LPO (Gilbert et al., 1991). It is yet
to be determined what this ‘‘ﬂow’’ actually is. Probably the engrams are
not translocated from one store to another, but memory consolidation
or mechanisms of retrieval require different forebrain areas to be acti-
vated successively.
Interim Summary After a single exposure, chicks learn to avoid
pecking a bead with a bitter substance. IMHV, the forebrain structure
that is of prime importance for imprinting, also seems to be essential
for this kind of one-trial avoidance learning. The ﬁrst and most promi-
nent cellular changes after the ﬁrst peck seem to occur in the left IMHV,
but the right IMHV and, most important, both sides of the LPO (parts
of the basal ganglia) are subsequently involved. Thus, the trace seems
to ‘‘ﬂow’’ from one area to the next in a lateralized fashion.
Figure 1.6Schematic frontal section through the forebrain of a chick showing the posi-
tion of the intermediate medial hyperstriatum ventrale (IMHV) and the lobus parolfac-
torius (LPO). According to the ‘‘memory ﬂow’’ model of Rose (1991), the engram for passive
avoidance learning is ﬁrst held in the left IMHV (1), then moves to the right IMHV (2),
and then is further transmitted to the LPO of both hemispheres (3).
23 Avian Visual Asymmetry

THE DEVELOPMENT OF AVIAN VISUAL LATERALIZATION
Embryos of virtually all avian species keep the head turned so that the
right eye is exposed to light shining through the translucent shell while
the left eye is occluded by the body (Kuo, 1932) (ﬁgure 1.7). Since
brooding parents regularly turn their eggs and often leave their nests
for short time periods, the embryo’s right eye has a high probability of
being stimulated by light before hatching. Thus, it is conceivable that
asymmetry of light stimulation is the key event leading to visual later-
alization. Indeed, dark incubation of chick and pigeon eggs prevents
the establishment of visual lateralization in grain-grit discriminations
(Rogers, 1982; Gu¨ntu¨rku¨n, 1993), and a mere 2 h of light exposure with
400 lux within the last days before hatch sufﬁces to establish visual
lateralization in dark-incubated chicken eggs (Rogers, 1982). It is even
possibletoreversethedirectionofthebehavioralandthethalamofugal
asymmetrybywithdrawingtheheadofthechickenembryofromthe
egg before hatch, occluding the right eye and exposing the left to light
(Rogers & Sink, 1988; Rogers, 1990).
Figure 1.7A pigeon embryo during hatching. Note the position of the head, which is
bent forward and points to the right. The right wingbud rests on the beak.
24 Onur Gu ¨ntu¨rku¨n

Since pigeons are altricial animals, the developmental plasticity of
their visual pathways is prolonged and extends far into posthatching
time (Manns & Gu¨ntu¨rku¨n, 1997). Therefore, covering the right eye of
newly hatched pigeons for 10 days reverses the anatomical asymmetry
of tectal soma sizes and the behavioral visual lateralization of these
animalsastesteduptothreeyearslater(Manns&Gu ¨ntu¨rku¨n, 1999a).
Thus, light stimulation asymmetry during a critical ontogenetic time span
seems to be the trigger for visual asymmetry in pigeons, as it is in chicks.
In principle, these results are in accordance with ﬁndings from mon-
ocular deprivation studies in mammals. These experiments reported
smaller soma sizes of neurons receiving afferents from the deprived eye
(Sherman & Spear, 1982). This is similar to pigeons, where the right
retinorecipient tectal neurons contralateral to the eye with the ‘‘natural
monocular deprivation’’ are smaller.
However, different mechanisms must be involved. Morphological
soma size effects of monocular deprivation in mammals are regarded
as secondary consequences of synaptic competition at the cortical level
between geniculate ﬁbers representing the deprived eye and the non-
deprived eye (Rauschecker, 1991). However, a detailed analysis in pi-
geons shows that ‘‘natural monocular deprivation’’ effects also occur in
those neural structures in which a comparable competition is absent
(Gu¨ntu¨rku¨n, 2001). This suggests that visual deprivation effects in birds
are mediated through activity-correlated, and eventually trophic, dep-
rivation effects within one hemisphere, and that they possibly operate
without direct synaptic competition between neurons representing the
deprived eye and the nondeprived eye.
In addition, only the unilateral absence of contoured visual patterns
induces signiﬁcant deprivation effects in the mammalian geniculocorti-
cal system. Asymmetries of luminance alone do not lead to alterations
(Movshon & Van Sluyters, 1981). This supports the assumption that
ﬁber competition is mediated by a Hebbian mechanism which requires
correlated activity of pre- and postsynaptic cells for stabilization or
retraction of synapses (Rauschecker, 1991). In chicks and pigeons, the
situation must be different, since light has to shine through the eggshell
and the closed lid of the embryo to induce cerebral asymmetries. There-
fore, avian asymmetry triggered by ‘‘natural monocular deprivation’’
has to be induced by brightness and not by contoured visual pattern
differences. Brightness differences are probably coded by mere activ-
ity differences between the eyes, and could induce asymmetries by
activity-dependent cellular effects.
25Avian Visual Asymmetry

Prehatch light stimulation asymmetry seems to be theconditio sine
qua nonto induce visual lateralization of object discrimination. It is,
however, not essential for other forms of visually guided behavior.
Dark-incubated chicks have functional asymmetries in imprinting
(Johnston & Rogers, 1998) and display biochemical left-right differences
in IMHV (Johnston et al., 1995). These asymmetries can, however, be
altered by a lateralized light input (Johnston et al., 1997; Johnston &
Rogers, 1999). Therefore, for some asymmetries (visual discriminations)
a lateralized light input is critical to induce neural left-right differences.
In other lateralizations (imprinting), asymmetries are prewired but can
be altered by a biased light input.
ASYMMETRY PAYS
This overview has shown that visual lateralization in birds depends on
an interaction of genetic factors that induce a torsion of the embryo’s
head to the right and the epigenetic factor light that subsequently
induces higher levels of activity in the right eye system. As a conse-
quence, neuronal systems are altered during a critical developmental
period in a lateralized way such that multiple aspects of visually guided
behavior of the animals are asymmetrically organized. Is all thisl’art
pour l’art, an epiphenomenon without costs but also without beneﬁts
for the animal? Or does visual lateralization pay? To seek an answer,
Gu¨ntu¨rku¨n et al. (2000) determined the individual asymmetry index of
108 pigeons by separately analyzing their left- and right-eye perform-
ances in grain-grit discrimination. Then the animals were tested on the
same task binocularly, and their discrimination success was correlated
with their asymmetry index. Animals with higher asymmetries were
signiﬁcantly more successful in discriminating grain from grit. This
means that a rise in asymmetry resulted in a concomitant rise of food
reward (ﬁgure 1.8). Thus, asymmetry pays.
LESSONS FROM THE AVIAN BRAIN
Birds heavily rely on vision. If asymmetry pays, it is understandable
that it is their visual system which is lateralized. Likewise, it is possible
that asymmetries of language or manual skills improve human perfor-
mance. According to the studies on avian lateralization, it might even
be conceivable that these and other human asymmetries emerge during
26 Onur Gu ¨ntu¨rku¨n

ontogeny due to subtle left-right differences that in the beginning affect
only subcortical mechanisms.
Indeed, as shown by Hepper et al. (1991), fetuses from 15weeks of
gestational age to term have a strong lateralized bias of thumb sucking
on the right side. The corticospinal tract cannot mediate this asymme-
try because it reaches cervical to thoracic segments much later and even
at term is myelinated only as far caudally as the cerebral peduncles
(Stanﬁeld, 1992). Even in the adult the rubrospinal tract reaches only as
far as the uppermost cervical segments, and the olivospinal pathway
known from studies in rats seems not to exist in man (Nathan & Smith,
1982). The lateral subcorticospinal pathway, which encompasses a va-
riety of descending tracts crucial for distal limb and hand movements,
myelinates only at 28–34 weeks of gestational age (Sarnat, 1984). Thus,
thumb sucking in the early fetus is mediated virtually only by spinal
mechanisms without relay through cortical relays (Sarnat, 1989). In
addition, asymmetrical gene expression mechanisms in early neuro-
ontogeny result in a slight torsion of the embryo with the forehead
turning to the right (Ramsdell & Yost, 1998).
This last point is probably common to all vertebrates, and could re-
sult in a higher probability of mouth-hand contacts on the right side.
The rightward spinal torsion could also be the reason why most new-
borns still have a preference for a right turn of their head when in a
supine position (Michel, 1981)—a preference that correlates with sub-
sequent handedness (Michel & Harkins, 1986). Therefore, a lateraliza-
Figure 1.8Relationship between the degree of lateralization and binocular discrimina-
tion performance. Pearson’s product moment correlation (scatter plot) reveals higher
performanceinmorelateralizedindividuals.(AdaptedfromGu¨ntu¨rku¨n et al., 2000.)
27 Avian Visual Asymmetry

tion of hand-mouth and hand-eye contacts in humans probably depends
on spinal asymmetries. If they are manifested in early neuro-ontogeny,
they may bias the processing mode of cortical structures that later con-
nect to those motoneurons which innervate the hands and which are
known to be signiﬁcantly larger on the right side (Melsbach et al., 1996).
Therefore, the initial bias for handedness might start subcortically, then
be controlled much later by cortical structures. Thus, at least some hu-
man asymmetries might display a developmental pattern comparable
with that outlined for birds.
CONCLUSIONS
1. In birds, visual information is treated in a lateralized fashion. While
object discrimination is left-hemisphere based, geometrical aspects of
spatial encoding and social recognition are primarily processed in the
right hemisphere.
2. This visual lateralization is also reﬂected in tasks, like imprinting and
one-trial-avoidance learning, in which the animal very quickly forms
a mental trace of the visual characteristics of a biologically relevant
object.
3. The lateralized behavior corresponds to asymmetries in the mor-
phology and connectivity of the ascending visual pathways. These
anatomical asymmetries can vary between species. Thus, seemingly
similar asymmetries of behavior can be generated by different lateral-
ized neural systems.
4. At least in pigeons, visual lateralization seems to be dually coded;
anatomically, by morphological and connectional differences of ascend-
ing visual pathways, and physiologically, by asymmetrical commissural
interactions that result in a lateralized modulation of visual processing.
5. In the last days before hatching, avian embryos bend forward and
keep their head turned to the right in such a way that the right eye
is exposed to light which is shining through the translucent eggshell,
while the left eye is occluded by the body. Ontogenetically, visual
lateralization of object discriminations is triggered by the subsequently
stronger light input to the right eye. This lateralized stimulation in-
duces asymmetrical morphological effects within the developing visual
system, and thereby establishes left-right differences at the behavioral
level.
28 Onur Gu ¨ntu¨rku¨n

6. Birds with higher visual asymmetries are superior in visual discrim-
inations. Thus, asymmetry increases efﬁciency of processing within the
visual system.
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35Avian Visual Asymmetry

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She went further, and bustling her arms against Edith’s shoulders,
purported to kiss her on both cheeks. Then, drawing back her head,
she went on: “My dear, the duke died at two this morning! It’s in all
the papers. But what isn’t in any of the papers is that the heir is
missing. It’s a very curious story. Mr. Westland here”—by her gesture
it seemed that Dicky was behind her in the hallway—“went to Duke
Street this noon, and found Christian’s man in great alarm. The
youngster had bolted, leaving a note saying merely that he was
called away. Mr. Westland’ then hunted me up, and we started out,
for I had a kind of clue, don’t you see. I knew where he was at ten
o’clock this forenoon—and we drove to Arundel Street, and there we
found——”
Christian hurriedly stepped forward. “Oh, I think you may take it
that I am not lost,” he called out, revealing himself to the astonished
Cora. For the moment the chief thing in his mind was satisfaction at
having interrupted her disclosures about Arundel Street.
Then, as other thoughts crowded in upon him, he straightened his
shoulders and lifted his chin. “It’s all right,” he said, with a
reassuring wave of the hand toward the womenfolk of his family.

PART IV

O
CHAPTER XXII
n the morning of the funeral, six days later, Christian rose
very early, and took coffee in his library shortly after seven.
Then, lighting a cigarette, he resumed work upon several
drawers full of papers, open on the big table, where it had been left
off the previous evening. The details of the task seemed already
familiar to him. He scanned one document after another with an
informed eye, and put it in its proper pile without hesitation. He
made notes suggested by the contents of each, on the pad before
him, with a quill pen and corrected the vagaries of this
unaccustomed implement, in the matter of blots and inadequate
lines, with painstaking patience. There were steel nibs in abundance,
and two gold stylographic pens, but he clung resolutely to the
embarrassing feather.
After a time he rested from his labors, and rang the bell beside his
desk; almost upon the instant Falkner appeared in the doorway.
“If Mr. Westland is up,” said Christian, “you may ask him to join
me here.”
“Yes, Your Grace,” the smooth-voiced, soft-mannered man replied,
and vanished.
The young duke rose, yawned slightly and moved to the window
nearest him. It opened, upon examination, and he stepped out on a
narrow balcony of stone which skirted the front of the square tower
he had quitted. The outlook seemed to be to the northeast, for a
patch of sunshine lay upon the outer edge of the balcony at the
right. Breathing in delightedly the fresh Maymorning air, he gazed
upon the bold prospect of hills receding in lifted terraces high
against the remote sky-line. He had not seen just this view from
Caermere before—and he said to himself that it was finer than all

the others. Above each lateral stretch of purplish-gray granite, to the
farthest distance, there ran a band of cool green foliage—the
inexpressibly tender green of young birch trees; their thin, chalk-
white stems were revealed in delicate tracery against indefinable
sylvan shadows.
Through the early stillness, he could hear the faint murmur of the
Devon, gurgling in the depths of the ravine between him and the
nearest hill. “To-morrow,” he thought, “will begin the true life! All this
will be my home—mine! mine! and before anybody is up in the
morning I will be down where that river of black water runs, and fish
in the deep pools for trout.”
Some one touched his elbow. He turned with a quick nod and
smile to greet Dicky Westland. “I am up ages before you, you see,”
he said genially. “It was barely daylight when I woke—and I suffered
tortures trying to remain in bed even till six. Oh, this is wonderful
out here!”
“Awfully jolly place, all round,” commented Dicky. He blinked to
exorcise the spirit of sleep and gazed at the prospect with
determined enthusiasm. “I haven’t looked about much, but I’ve
found out one thing already. There’s a ghost in my room—and I
think he must have been a professional pedestrian in life.”
“Splendid!” cried Christian, gaily. “Have you had coffee—or it is tea
you people drink, isn’t it? Then shall we get to work? I want the
papers out of the way before Emanuel comes. They will all be here
between nine and ten. I wanted to send carriages to Craven Arms,
but it seemed there were not horses enough, so hired traps are to
be brought up from the station.”
“Do you know who are coming?”
“Lord Julius, and Emanuel and his wife; the captain and his wife
and brother; Lord Chobham, and Lord Lingfield—I don’t know if any
of their women will come—and Lady Cressage. Then there are some
solicitors, and perhaps some old acquaintances of my grandfather’s.

At all events, Welldon has ordered four carriages and a break. There
is to be breakfast at ten, and I shall be glad when it is all over—
when everything is over. Do you know?—I have never been to a
funeral in my life—and I rather funk it.”
“Oh, they’re not so bad as you always think they’re going to be,”
said the secretary, consolingly. “The main thing is the gloves. I never
could understand it—but black gloves are invariably about two sizes
smaller than ordinary colors. You want to look out for that. But I
dare say your man is up to the trick—he looks a knowing party, does
Falkner.”
“I fancy I shall give him back to Emanuel,” remarked Christian,
thoughtfully.
“He is an excellent servant, but he reminds me too much of Duke
Street. Did you notice the old butler yesterday afternoon?—he stood
at the head of the steps to meet us—that is old Barlow. I have a
great affection for him. I shall have him valet me, I think.”
“Isn’t he rather venerable for the job?” suggested the other. “And
wouldn’t it be rather a come-down for a head butler? They’re awfully
keen about their distinctions among themselves, you know.”
Christian smiled with placidity. “I think that the man whom I pick
out to be nearest me will feel that he has the best place in the
household. I shall be very much surprised indeed if that isn’t
Barlow’s view. And of course he will have his subordinates. But now
let us take Welldon’s statement for the last half of ’95, and the two
halves of ’96. Then we can get to the mine. Unless I am greatly
mistaken, that is most important. I find that the mining company’s
lease falls in early next year. And won’t you ring the bell and have
Welldon sent up when he comes?”

Upon mature reflection Christian decided not to descend to meet
his guests at breakfast. When he had dismissed the estate agent,
Welldon, after a prolonged and very comprehensive interview, he
announced this decision to Westland. “You must go down and
receive them in my place,” he said.
“I will say that you have a cold,” suggested Dicky.
“By no means,” returned Christian, promptly.
“It is not necessary to enter into details. You receive them—that is
all. I have spoken with Barlow; he knows what to do with them in
the matter of rooms and so on. I am breakfasting here. And
afterward—say at eleven o’clock—I will see some of them here.
There is an hour to spare then, before we go to the church. I am not
clear about this—which ones to see first. There is that stupid reading
of the will after we get back——”
“By George! do they do that still?” interrupted Dicky. “I know they
did in Trollope and George Eliot—but I thought it had gone out.”
“It is kept up in old families,” replied Christian, simply. “In this
case it is a pure formality, of course. There is no mystery whatever.
The will was made in 1859, after the entail was broken, and merely
bequeaths everything in general terms to the heir-at-law. My
grandfather covenanted, at the same time, to Lord Julius to make no
subsequent will save by his advice and consent—so that there can
be no complications of any kind. I am thinking whether it would be
better to see Lord Julius and Emanuel before the reading of this will
or after. Really it makes no difference—perhaps it is better to get it
over with. Yes—say to them that I beg they will come to me here at
eleven. You might bring them up and then leave us together—or no,
they know the way. Let them come up by themselves.”

Through the open window there came the grinding sound of
wheels upon the gravel of the drive, around at the east front. At a
gesture from the other, Dicky hurried away.
Left to himself, Christian wandered again to the casement, and
regarded the spacious view with renewed interest. Falkner entered
presently, bearing a large tray, and spread some covered dishes
upon a cloth on the library table.
“How many carriages have come?” the master asked from his
place at the window.
“Four, Your Grace—and a break with some wreaths and Lord
Chobham’s man and a maid—I think it is Lady Cressage’s maid.”
“Who has come—outside the family?”
“Three gentlemen, Your Grace—one of them is Mr. Soman. Barlow
thinks they are all solicitors.”
Christian mused briefly upon the presence of Lord Julius’s man of
business. Since that first evening of his on English soil, at Brighton,
he had not seen this Mr. Soman. He remembered nothing of him,
indeed, save his green eyes. And now that he thought of it, even
this was not a personal recollection. It was the remark of the girl on
the boat, about his having green eyes, which stuck in his memory.
He smiled, as he looked idly out on the hills.
The girl on the boat! Was it not strange that his mind should have
applied to her this distant and chilling designation? Only a few days
ago—it would not be a week till to-morrow—she had seemed to him
the most important person in the world. A vision of his future had
possessed him, in which she alone had a definite share. How remote
it seemed—and how curious!
He recalled, quite impersonally, what he had heard in one way or
another about her family. Her father was some sort of underling in
the general post office—a clerk or accountant, or something of the
kind. There was a son—of course, that would be the brother Cora

had spoken of—and the ambition of the family had expended itself in
sending this boy to a public school, and to the university. The family
had made great sacrifices to do this—and apparently these had been
wasted. He had the distinct impression of having been told that the
son was a worthless fellow. How often that occurred in England—
that everything was done for the son, and nothing at all for the
daughters! Then in fairness he reflected that it was even worse in
France. Yes, but somehow Frenchwomen had a talent for doing for
themselves. They were cleverer than their brothers—more helpful,
resourceful—in spite of the fact that the brothers had monopolized
the advantages. Images of capable, managing Frenchwomen he had
known rose before his mind’s eye; he saw them again accomplishing
wonders of work, diligent, wise, sensible, understanding everything
that was said or done. Yet, oddly enough, these very paragons of
feminine capacity had a fatal unfeminine defect; they did not know
how to bring up their sons. Upon that side they were incredibly weak
and silly; it was impossible to prevent their making pampered fools
of their boys.
Suddenly his vagrant fancies were concentrated upon the question
of how Frances Bailey would bring up a boy—a son of her own. It
was an absurd query to have raised itself in his mind—and he put it
away from him with promptitude. There remained, however, a kind
of mental protest lodged on her behalf among his thoughts. He
perceived that in his ruminations he had done her an injustice. She
was not inferior in capability or courage to any of the self-sufficient
Frenchwomen he had been thinking of, and in the matter of
intellectual attainments was she not immeasurably superior to them
all? The translucent calm of her mind—penetrating, far-reaching,
equable as the starlight—how queer that it should be coupled with
such a bad temper! She always quarreled with him, and bullied him,
when they were together. Even when she was exhibiting to him the
sunniest aspects of her mood, there was always a latent defiance of
him underneath, ready to spring forth at a word. He remembered
how, at the close of their first meeting, she had refused to tell him
her name. He saw now that this obstinacy of hers had annoyed him

more than he had imagined. For an instant it assumed almost the
character of a grievance—but then his attention fastened itself at
random upon the remarkable fact that he had seen her only twice in
his life. Upon reflection, this did seem very strange indeed. But it
was the fact—and in the process of readjusting his impressions of
the past six months to fit with it, the figure of her receded in his
mind, grew less as she moved away under a canopy of dull
yellowish-green, which vaguely identified itself with the trees on the
Embankment. She dwindled thus till he thought of her again, with a
dim impulse of insistence upon the phrase, as the girl on the boat.
The transition to thoughts of other things gave his mind no sort of
trouble.
He pondered some of these other things—formlessly and light-
heartedly—while he stood at the library table, and picked morsels
here and there from the dishes laid for him. His absence of appetite
he referred tacitly to the warmth of the day, as it was sunnily
developing itself outside. Here on this shaded side of the castle, it
was cool enough, but there was the languor of spring in the air. He
scrutinized this new library of his afresh. Until Barlow had opened it
for him, shortly after his arrival yesterday, it could not have been
used for years. Most of its appointments had a very ancient look; no
doubt they must date back at least to the seventh Duke’s time. It
was incredible that his grandfather, the eighth Duke, should have
been inspired to furnish a library. There were many shelves of
apparently very old books as well, but there was also a vast deal of
later rubbish—stock and sporting annuals, veterinary treatises,
county directories and the like—which he would lose no time in
putting out. He saw already how delightful a room could be made of
it. It had the crowning merit of being connected with the suite of
apartments he had chosen for his own. From the door at the side,
opposite the fine old fireplace, one entered the antechamber to his
dressing-room. This gave to the library an intimate character, upon
which he reflected with pleasure. Here he would come, secure from
interruption, and spend among his books the choicest and most
fruitful hours of his leisure. It was plain to him that henceforth he

would do a great deal of reading, and perhaps—why not?—of writing
too.
There was a rap upon the door, and then Falkner, opening it,
announced Lord Julius and his son. They came in together, diffusing
an impalpable effect of constraint. The elder man seemed in
Christian’s eyes bigger than ever; his white beard spread over the
broad chest like a vine run wild. Emanuel, who lapsed in the wake of
his father, was unexpectedly small by comparison. The shadows,
where the two stood, emphasized the angular peculiarities of his
bald head. His thin face took an effect of sallow pallor from his black
clothes. Already he had his black gloves in his hands.
Christian stepped forward to meet them—and was suddenly
conscious of the necessity for an apology. “I did not come down,” he
murmured, as he shook hands with a grave smile—“I am not quite
master of myself yet. It is still strange to me. But come to the
window, and let us sit down.”
They followed him, and took the chairs he pushed out for them.
He perched himself on the corner of the big table, and lightly
stroked the glazed boot of the foot which was not on the floor. “I am
glad to hear that Kathleen has come,” he said to his cousin. “I hope
she is very well.”
“Extremely so,” replied Emanuel. Then, upon reflection, he added,
“We had hoped that you would come to us, on your way down from
London.”
“There was so much to do in town,” explained Christian, hazily.
“My grandfather’s lawyers came up at once from Shrewsbury, and it
was necessary to see a good deal of them—and then there were the
tailors and outfitters. It was all I could do to get away yesterday
morning. And of course—by that time I was needed here.” He turned
to the other. “And you are very well, Uncle Julius?”
“I am well,” said the elder man, with what Christian suspected for
the instant to be significant brevity. The father and son had

exchanged a look, as well, which seemed to have a meaning beyond
his comprehension. But then he forgot these momentary doubts in
the interest of the discovery that there were tears in his great-
uncle’s eyes.
Lord Julius unaffectedly got out a handkerchief, and wiped them
away. He looked up at the young man as through a mist. “I never
dreamed that I should feel it so much,” he said, huskily. “I am
amazed at myself—and then ashamed at my amazement—but Kit’s
death has somehow put me about and upset me to a tremendous
extent. There was thirteen years between us—but when you get to
be an old man, that seems no more than as many weeks. And
Emanuel”—he addressed his son with the solemnity befitting a
revelation—“I am an old man.”
Emanuel frowned a little in his abstracted fashion. “You are less
old than any other man of your years in England,” he protested.
Christian, listening, somehow found no conviction in these
reassuring words. It dawned upon him suddenly that Lord Julius had
in truth aged a great deal. The perception of this disarranged the
speech he had in his mind.
“There are a thousand things to be talked over,” he began, with an
eye upon Emanuel, “but I do not know if this is quite the opportune
time. I wished to lose no time in seeing you both, of course—but
you will not be hurrying away. No doubt there will be a better
opportunity.”
“I don’t think it will be found that there is so very much to say,”
remarked Emanuel. A gentle but persistent melancholy seemed to
pervade his tone.
“There is the complication”—Christian began again, and hesitated.
“That is to say—you know even better and more fully than I do, to
what a great extent I am in your hands. And there the complication,
as I said, arises. I have been working very hard on the figures—with
the lawyers in London, and here since I arrived—but before we

touch those at all, I ought to tell you frankly, Emanuel: I do not see
my way to meeting the conditions which you suggested to me last
autumn, when we met first.” Emanuel seemed in no wise perturbed
by the announcement. His nervous face maintained its unmoved
gravity. “It was never anything more than a pious hope that you
would,” he commented. “I may add,” he went on, “that even this
hope cannot be said to have survived your first visit. Otherwise, I
should have tried to have you see London under different auspices—
through different eyes.”
The calmness with which the decision he had regarded as so
momentous met acceptance disconcerted Christian. He had mentally
prepared for the defense of his hostile attitude toward the System—
and, lo! not a syllable of challenge was forthcoming.
“But there remains, all the same, the principal difficulty,” he said,
thinking hard upon his words. “It does not lessen my obligations to
you as my chief creditors.” He looked from one to the other, as if in
uncertainty as to which was the master mind. “You have both been
very open with me. You have told me why it was that you devoted a
large fortune to buying up the mortgages on the estate which is now
mine—and to lending always more money upon it—until now the
interest eats up the income like a visitation of locusts. But my
knowledge of the motives does not help me. And you must not
think, either,” his confidence was returning now, and with it a better
control over his phrases—“that I am begging for help. I look the
situation in the face, and I do not feel that I am afraid of it. I see
already many ways in which I can make a better fight of it than my
grandfather made.”
Lord Julius held up a hand. “Is there not a misconception there?”
he asked, pleasantly enough. “A fight involves antagonists—and I
intervened in poor Kit’s affairs as a protector, not as an assailant.”
Christian stood erect, and knitted his brows in puzzled thought
upon both the manner and the matter of these words.

“But it is still the same,” he persisted. “You were his good friend—
as I know you are mine—or hope very sincerely that you are—but
none the less you were his overwhelmingly big creditor, as now you
are mine. If one is greatly in debt, then one struggles to get out. It
is in that sense that I meant the word ‘fight.’ And, to repeat, I see
many ways of making progress. I find that Welldon is not exclusively
my man. He is the agent of three other estates as well, because we
could not pay him enough here for all of his services. That I will alter
at once. I find that we have no mineral bailiff. The company at
Coalbrook has paid such royalties as it pleased, without check of any
sort. We have the right to examine their books, but it has never
been exercised. Next week my secretary and Welldon go to
Coalbrook. I find that the company’s lease of twenty-one years
expires next February. Eh bien! It will be strange if I do not get ten
thousand pounds hereafter, where less than four has come in
hitherto. My lawyers already know of capitalists who desire to bid for
the new lease—and the estimate of increase is theirs, not mine. But
these are details. I mention them to you only to show you that I am
not afraid. But anxious, I do not deny that I am. I have not been
bred to these things—and I may easily make mistakes. It would take
a great load off my mind if—if, in some measure, you would be my
advisers as well as my creditors.”
“Why should you ever have doubted that?” asked Emanuel, in a
tone of somber kindliness.
“Ah, but I do not mean advice about the management of the
estate,” put in Christian, with an over-eager instinct of self-defense.
“I do not shrink from taking that completely on my own shoulders. I
would not trouble you with anything of that sort. But of larger
matters——”
“There is one large matter,” interrupted Lord Julius, speaking with
great deliberation, “which I find outweighing all others in my mind.
It is not new to my mind—but to-day it pushes everything else
aside. It is the thought of the family itself. I have told you this before
—let me say it to you again. Everything that I have done—every

penny that I have laid out—has been with this one end in view—the
family. Yet this morning I have been thinking of it—and I am
frightened. While poor old Kit lingered along, it was not so easy to
grasp it, somehow—but his going off makes it glaring. There are too
few of us. I am alone in my generation—and so is Emanuel in his—
and so are you in yours, save for those rowdy simpletons Eddy and
Gus. And beyond you, there is only that little girl baby of Cora
Bayard’s! I want you to marry, Christian. I want to see sons of yours
growing up here at Caermere—hearty, fine boys to carry the name
of Torr along. That I am really in earnest about. By comparison with
it, nothing else on earth matters—for us.”
“Oh, I shall marry,” Christian replied, in smiling seriousness. “Of
course, that is the obvious thing to be done. And now”—he looked at
his watch—“it is time for me to dress. It is arranged that you and
Emanuel and Kathleen drive to the church in the carriage with me. It
is not quite orthodox precedence, I know, but I could not bear to—
to have it otherwise. And we will think no more about those other
matters until tomorrow.”
“Other matters,” repeated Lord Julius, and exchanged a look with
his son as they rose. “My dear Christian, there are no other matters.”
“No—not till to-morrow,” answered Christian, with a doubtful
smile. “But then I am afraid there are a good many.”
Emanuel filled in the pause. “Mr. Soman has brought all the
papers,” he said, with a flitting return to his lighter manner. “It is my
father’s meaning that the mortgages are extinguished.”
Christian gazed from one to the other with a face full of
stupefaction. His knees shook and sought to bend under him.
Tremblingly he essayed to speak—and his lips would make no sound.
Lord Julius laid his big hand on the young man’s shoulder—and
Christian, dimly recalling the effect of this touch in the days when he
had first known it, thrilled at the novel restfulness it somehow now
conferred.

“Only show me a son of yours,” said the old man, with tender
gravity. “Let me see an heir before I die.”
Without further words, the two left him. Christian, staring at the
shadowed door through which they had vanished, remained
standing. His confused brain quailed in the presence of thoughts
more stupendous than the ancient hills outside.

S
CHAPTER XXIII
everal thousand people caught that day their first curious
glimpse of the new master of Caermere. At the most there
were but a handful of aged persons, in the throng clustered
along the sides of the road winding down from the Castle to the
partially restored medieval collegiate church in the valley, who could
remember any other duke than the one being borne now to lie
among his fathers. The fact that these venerable folk, without
exception, were in the enjoyment of a day’s holiday from the
workhouse, might have interested a philosopher, had it been pressed
upon his attention.
Quite two hundred horsemen, mounted in their own saddles on
their own beasts, rode in the long procession which descended from
Caermere toward the close of the noon hour. Clad in decent black for
the greater part, with old silk hats or other formal and somber
headgear, they jogged sedately in unison as the curbed horses
stepped with caution down the hill. Their browned and large-
featured faces wore a uniform mask of solemnity—distinguished
chiefly by a resolute contraction of brows and lips, and eyes
triumphantly cleared of all traces of speculation. They looked down,
as they passed, upon the humbler dalesmen and laborers of the
hillsides, and their womenfolk and swarming children, with an
impassive, opacated gaze.
On the green, before the little covered gateway to the churchyard,
dull murmurs spread through this cortege, propelled sidelong from
mouths which scorned to open; the main principles of a proposed
evolution came slowly, in some mysterious way, to be comprehended
among them: after almost less backing and pushing into one
another than might have been expected, they perceived themselves
emerging into an orderly arrangement, by which they lined the two

sides of the carriage-way crossing the green. They regarded each
other across this significant strip of gravel with a gloomy stolidity of
pride: the West Salop Yeomanry could scarcely have done it better.
Then another rustle of whispered sounds along their ranks toward
the church—and the civic side of their demonstration came
uppermost. With a tightened left hand upon the reins, they removed
their hats, and held them so that they could most readily read the
names of the makers inside.
The carriages bearing the family of Torr, preceded by the curtained
hearse, and followed by a considerable number of broughams and
closed landaus recognizable as the property of the neighboring
gentry, moved silently forward along this lane of uncovered
horsemen. The distant swelling moan of the organ floated on the
May air, in effect a comment upon the fact that the tolling of the bell
in the tower had ceased.
The intermittent noise of carriage-doors being sharply shut, and of
wheels getting out of the way, proceeded from the head of the
procession at the gate—and tenants and other undistinguished
people on foot began to press forward between the ranks. The
horsemen, with furtive glances to right and left, put on their hats
again, and let the restive animals stretch their muscles in the path. A
few, dismounting, and giving their bridles over to boys, joined those
who were moving toward the church. The majority, drawing their
horses aside into groups formed at random, and incessantly shifting,
lent their intellects, and in some restrained measure their tongues,
to communion upon the one great problem of the day:—would the
new Duke set the Hunt on its legs again?
The question was so intimately connected with their tenderest
emotions and convictions, that no one liked to speak of it
thoughtlessly or upon hasty impulse. Even those who doubted most,
shrank from hearing the prophecies of evil they felt prone to utter.
Men who nourished almost buoyant hopes still hesitated to create a
confidence which must be so precarious. While the faint sustained
recitative of the priest in the church could be heard, insistent and

disturbing like the monotone of a distant insect, and then the sounds
of the organ once more, and of singing, fell upon the sunlit green,
the horsemen spoke cautiously about the hounds. Even before Lord
Porlock’s death, things had not been what they should have been.
The pack was even then, as one might say, falling between two
stools. The Torrs hadn’t the money to keep the thing up properly
themselves, but they showed their teeth savagely the minute
mention was made of getting in some outside help. But since
Porlock’s death—well, the condition of affairs had been too painful
for words. The horsemen shook their heads in dumb eloquence upon
this tragic interval. The Kennels had lapsed into a state hardly to be
thought of, much less discussed. There had been no puppy-walk.
Were there any young dogs at all? And, just heavens! if there were,
what must they be like!
And yet the country-side, outraged as it felt itself to be in its finest
feelings, beheld itself helpless. The old Duke—but really this was not
just the time and place for saying what they felt about the old Duke
They glanced uneasily toward the church when this theme
suggested itself, and nodded with meaning to one another. It could
be taken for granted that there were no illusions among them
concerning him. But what about the new man? Eyes brightened, lips
quivered in beseeching inquiry, at the mention of this omnipotent
stranger. What was he like? Had anybody heard anything that
Welldon had said about him? It seemed that he was French bred,
and that, considered by itself, might easily involve the worst. But
then, was there not a story that he had ridden to the hounds in
Derbyshire? Perhaps the younger generation of Frenchmen were
better fellows than their fathers—but then, there was the reported
fact that the Duke of Orleans fell off his horse and broke his leg
whenever he tried to ride. Sir George had been informed in Paris
that he would have been King of France by this time if he had been
able to stick in a saddle. Yet, when one thought of it, did not this
very fact indicate a fine new public sentiment in France, on the
subject of horsemanship—and perhaps even of sport in general?

Christian, at the door of the church, had thought most of
clenching his teeth, and straining his upper-arms against his sides,
to keep from trembling. He had not pictured himself, beforehand, as
entering this burial place of his ancestors alone. Yet, in the
churchyard, that was how the matter arranged itself. His first idea
had been to lead, with Kathleen on his arm—but she had said her
place was with Emanuel instead. Then the alternative of walking
arm-in-arm with Lord Julius had seemed to him even more
appropriate—but this too, in the confused constraint of the moment,
had gone wrong. Stealing an anxious half-glance over his shoulder,
he discovered that Lord Julius had placed himself at Kathleen’s other
side. The slight gesture of appealing invitation which he ventured
upon did not catch the old man’s eye. There was nothing for it but to
stand alone.
To be the strange, unsupported central figure in such a pageant
unnerved him. He stood tremulously behind the pall—a burden
draped with a great purple embroidered cloth, and borne upon the
shoulders of eight peasant-laborers from the estate—and noted
fleetingly that, so stunted and mean of stature were these poor
hinds, he looked with ease above them, over their load, into the
faces of the two priests advancing down the walk toward him.
These persons, an elderly, dark man, with a red hood folded upon
his shoulders, and a thin-faced fair young man, seemed to return the
gaze with meaning. He caught himself feeling that their eyes
deferred to him; yes, if they had bowed to the ground, the effect of
their abasement before him could not have been more palpable.
Looking perfunctorily across the chasm of death, their glances
sought to, make interest with the living. He hated them both on the
instant. As they wheeled, and by their measured steps forward drew
slowly in their wake the bearers of the pall, the chant of the elder
—“I am the Resurrection and the Life”—came vaguely to his ears,
and found them hostile.
The interior of the old church—dim, cool, cloistral—was larger
than Christian had assumed from its outer aspect. Many people were

present, crowded close in the pews nearest the door—and strangely
enough, it was his perception that these were chiefly women, of
some unlabeled class which at least was not his own, that brought
to him of a sudden self-command. He followed the bier up the aisle
to its resting-place before the rail, took tacit cognizance of the place
indicated to him by some man in professional black, and stood aside
to let Kathleen pass in before him, all with a restored equanimity in
which he was himself much interested. Through the reading of the
Psalm and the Epistle he gave but the most vagrant attention to
their words. The priests read badly, for one thing; the whining
artificiality of their elocution annoyed and repelled him. But still
more, his thoughts were diverted by the suggestiveness of
everything about him.
Especially, the size of the funeral gathering, and of the mounted
and wheeled procession, had impressed him. There need be no
pretense that affection or esteem for the dead man had brought out,
from the sparsely populated country round about, this great
multitude. Precisely for that reason, it became a majestic fact. The
burial of a Duke of Glastonbury had nothing to do with, personal
qualities or reputation. It was like the passing away of a monarch.
People who cared nothing for the individual were stirred and
appealed to by the vicissitudes of an institution. Inset upon the walls
around him were marble tablets, and more archaic canopies of stone
over little carved effigies of kneeling figures; beyond, at the sides of
the chancel, he could see the dark, rectangular elevations of the
tombs, capped by recumbent mail-clad statues, with here and there
a gleam of gilt or scarlet retained from their ancient ornamentation;
even as he had walked slowly up the aisle, his downcast eyes had
noticed the chiseled heraldry of stones beneath his feet. Everywhere
about him was the historic impact of the Torrs. Their ashes were
here—their banners and shields and tilting-helmets, their symbolical
quarterings of the best arms of the West, their own proudest device
of all. Their white bull on the green ground was familiar in England
long before the broom-corn of the Angevins had been thought of.
The clerkly pun on Tor and Taurus was as like as not older than the

English language itself. All this made something mightier, more
imposing and enduring, than any edifice to be reared by man alone.
It was only in part human, this structure of the family. The
everlasting hills were a part of it, the dark ranges of forests, the
spirits and legends of the ancient Marches.
“In the morning it is green, and groweth up; but in the evening it
is cut down, dried up and withered,” droned the young clergyman.
But if man seemed to count for but little in this tremendous,
forceful aggregation of tradition and custom, yet again he might be
all in all. The tall old man under the purple pall, there—it was easy
to think contemptuously of him. Christian recalled, in a kind of
affrighted musing, that one view of his grandfather that he had had.
The disgust with which he had heard the stupid, violent words from
those aged lips revived within him—then changed to wonder. Was it
not, after all, the principle of strength which most affected men’s
minds? There had been discernible in that grandfather of his a
certain sort of strength—dull, unintelligent, sinister, half-barbarous,
but still strength. Was it not that which had brought forth the two
hundred horsemen? And if this one element, of strength—yes, you
might call it brute strength—were lacking, then would all the other
fine qualities in the world avail to hold the impalpable, intangible
combination together?
“‘He shall have put down all rule, and all authority, and power.’” It
was the old parson who was reading now.
“‘For He must reign, till He hath put all enemies under His feet.’”
Yes, even in this Protestant religion to which he had passively
become committed, force was the real ideal! Christian’s wandering
mind fastened itself for a moment upon the ensuing words of the
lesson, but got nothing from their confusing reiterations. He lapsed
into reverie again, then started abruptly with the sudden perception
that everybody in the church behind him must be looking at him. In
the pew immediately behind, there would be Captain Edward and his

wife, and Augustine; in the one behind that Lady Cressage, Lord
Chobham and his son; beyond them scores and scores of others
seated in rows, and then a throng in the aisle and the doorway—all
purporting to think of the dead, but fixing their eyes none the less
on the living. And it was not alone in the church, but through the
neighborhood, for miles round about: when men spoke of the old
Duke who was gone, their minds would in truth be dwelling upon
the new Duke who was come. A thrill ran through his veins as the
words spelled themselves out before his inner vision. The new Duke!
He seemed never to have comprehended what it meant before.
No; and till this moment no genuine realization had come to him
of this added meaning—this towering superstructure which the
message of Julius and Emanuel had reared. It was only now that he
hit upon the proper mental focus with which to contemplate this
amazing thing. Not only was he a territorial ruler, one of the great
nobles of Europe, but he was the master of wealth almost beyond
counting as well!
Those nearest to him were rising now, and he, obeying imperative
impulses within him, lifted himself proudly to his feet. While the air
throbbed with deep-voiced organ notes, in the pause which here
ensued, his gaze rested upon the pall before him. There was a sense
of transfiguration in the spectacle. The purple mantle became
imperial Tyrian to his eyes—and something which was almost
tenderness, almost reverence, yearned within him toward that silent,
incased figure hidden beneath it. The mystic, omnipotent tie of
blood gripped his heart.
With a collected sidelong look he surveyed the profiles of Emanuel
and Lord Julius to his left. Theirs were the lineaments of princes. As
if he had eyes in the back of his head, he beheld Edward and
Augustine, as fancy revealed them standing in the pew behind him.
Tall, slim, athletic, fair—the figures his imagination made of them
appealed to the new patriarchal spirit in his heart. Perhaps they
were not wholly nice, these young men, but they also were princes,

and they were of his race, and no one should persecute them, or
despitefully use them.
The uncouth little bearers of the dead had come forward again,
and taken up their burden. In a small lady-chapel, extending from
the transept at the left, the interment was to take place, and thither
Christian now followed the pall, leading the menfolk of his family and
the male guests of position who attached themselves to the group.
Thus some score of black-clad figures clustered round the oblong
opening in the old stone floor, and Christian, standing at its head,
glanced impassively over the undefined throng of spectators
gathered at the doorway.
“‘Man that is born of woman hath but a short time to live, and is
full of misery,’” proclaimed the younger priest, with a sudden
outburst of high-pitched, nasal tones which pierced the unexpectant
ear. “‘He cometh up and is cut down, like a flower; he fleeth as it
were a shadow, and never continueth in one stay.’”
Christian, watching abstractedly the impersonal wedge of faces at
the door, all at once caught his breath in a sharp spasm of
bewildered amazement. The little book he had been holding fell from
his hands, balanced on its edge for an instant and toppled over into
the dark vault below. He seemed unconscious of the incident—but
stared fixedly, with parted lips and astonished eyes, at the image of
something he had seen outside of the chapel. The thing itself had
apparently vanished. He perceived vaguely that people were looking
at him—and with a determined effort regained control of his face
and bearing. The puzzling thought that it might have been an
illusion—that perhaps he had seen nothing at all—brought mingled
confusion and solace to his mind. He put his hand to the open book
which Lord Julius at his side held toward him, and pretended to look
at it.
The coffin, now bereft of its purple covering, had been lowered to
its final place. One of the bearers, standing over the cavity, crumbled

dry earth from his tanned and clumsy fingers, and it fell with a faint
rattle upon some resonant, unseen surface.
The phrase, “‘Our dear brother, here departed,’” stuck out with
awkward obtrusiveness from among the words of the priest. “‘Earth
to earth, ashes to ashes, dust to dust.’” the sing-song went on. Then
they were repeating the Lord’s Prayer together in a buzzing, fitful
murmur. There were other prayers—and then Christian read in the
faces of those about him that the ceremony was finished. Accepting
the suggestion of Lord Julius’s movement, he also bent over, and
looked blankly down into the obscurity of the vault. But when he
lifted his head again, it was to throw a more searching and
strenuous glance than ever over the knot of people outside the door.
And yes!—he had not been deceived. He distinctly saw the face
again, and with lightning swiftness verified its features. Beyond a
shadow of doubt it was Frances Bailey whom he beheld,
mysteriously present in this most unlikely of places.
He withdrew his eyes and did not look that way again. The
question whether she knew that he had recognized her, occupied his
mind to the exclusion of all else, as he returned at the head of his
followers to the body of the church. It still possessed his thoughts
when he had joined the family group of chief mourners, loosely
collecting itself in the aisle before the front pews, in waiting for the
summons to the carriages. To some one he ought to speak at once,
and for the moment his eye rested speculatively upon Cora. He
identified her confidently, not only by her husband’s proximity, but
by the fact that her mourning veil was much thicker and longer than
any of the others. Some unshaped consideration, however,
restrained him, and on a swift second thought he turned to
Kathleen.
“I want you to look,” he whispered to her, inclining his head—“on
the other side of the church, just in a line between the second pillar
and the white-bearded figure in the window—there is a tall young
woman, with the gray and black hat. Do you see her? In a kind of

way she belongs to us—she is Cora’s sister, but I’m afraid if Cora
asked her, she would not come to the Castle.”
“Yes—once you talked to me about her,” Kathleen reminded him.
“Well, will you do this for me?” he continued, in an eager murmur.
“Go to her, and make sure that she promises to come up with the
rest. It would be unforgivable—if we let her go away.”
He had an uneasy feeling that Mrs. Emanuel’s veil did not prevent
her shrewd glance from reading him through and through—but he
did not seek to dissemble the breath of relief with which he heard
her assent.

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The Asymmetrical Brain Hugdahl Kenneth Davidson Richard J

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The Asymmetrical Brain Hugdahl Kenneth Davidson Richard J

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