Histology of cerebrum and cerebellum

Histology of cerebrum and cerebellum

1. HISTOLOGICAL FEATURES OF
CEREBRUM
CEREBELLUM
Prof.J.Anbalagan

2. CEREBELLUM

3. CEREBELLUM
•Hind brain-
–small brain

•Posterior cranial fosse

•Forms roof of IV ventricle

•Fissures and folia

4. CEREBELLUM
•Receives sensory data
–Same side spinal cord
–Dorsal and ventral
spinocerebellar tract

•Receives Motor data
–from cerebrum opposite
side
–Cortico pontine fibers

•Output is motor in function

5. CEREBELLUM
•Cerebellum
–controls the activity of cerebrum and
spinal cord

–dysfunctions
•manifested by disturbances in the motor
functions without voluntary paralysis

•Resulted in clumsy, poorly coordinated
loss of skillful movements

6. CEREBELLUM-Functions
•Responsible for
Equilibrium
Controls eye and head movements
balancing

Postural changes
Muscle tone

Smooth execution of voluntary
movements
Accuracy
Perfection
control

7. White fibers - afferent
•Mossy fibers
–Spinal cord

–Vestibular nucleus

–Pons

•Enters through inferior and middle cerebellar
peduncle

•Synopses with Purkinje cells through granular
cells

8. White fibers- afferent
•Climbing fibers
–Olivary nucleus
–Accessory olivary nucleus

•Through inferior peduncle

•Enters directly to molecular layer

•Synapses with Purkinje 1:1

9. White fibers - efferent

•Axons of Purkinje
( except archicerebellum)

•Deep nuclei of
cerebellum

•Through superior
cerebellar peduncle

10. Cerebellum-cortex
•Pia mater

•Cortex and white fibers

•Cortex-Three layers

•Type of cells
–Stellate cells
–Basket cells
–Purkinje cells
–Granule cells
–Golgi type II

•White fibers
–Climbing fibers
–Mossy fibers

11. CEREBELLUM
•Layers of cerebellum

•Molecular layer
–Dendrite orborization
–Densely packed axons run
parallel to surface
–Superficially stellate cells
–Deeper stellate cells
known as basket cells

•Purkinje layer

•Granular layer
–Closely packed granule
cells
–Shows clear zones -
glomeruli

12. CEREBELLUM

13. PURKINJE NEURON
Stellate cells
Basket cell

14. CEREBELLUM-GOLGI STAIN
PURKINJEE NEURONS

15. Cerebellum-dendrite tree

16. Cerebellum-granular layer-(rosette)

17. Molecular layer
Granular layer
Purkinje layer

18. CEREBELLUM
MOLECULAR
LAYER
GRANULAR
LAYER

19. MOLECULAR LAYER
GRANULAR LAYER
PURKINJE LAYER

21. Cerebrum
•White matter
–Nerve fibers
•Commissural
•Association
•Projection
•Gray matter
–Neurons
–Neuroglia cells

22. Cerebral cortex- type of neurons
•Six type of neurons
•Pyramidal
–Triangular
–Dendrite arises from three
angles
–Axon from the base of cell
–Prominent nucleus and Nissl
substances
–Small sized pyramidal
neuron10-12 micron
–Medium sized neuron 40-50
micron
–Large sized (Betz cells ) > 100
micron

23. •Stellate/granular cells
–Polygonal/triangular
shape
–Dark condensed nucleus
–Dendrites arises all over
–Axon terminate next
layer and goes deeper

•Fusiform cells
–Oriented perpendicular
to the surface
–One dendrites towards
superficially
–One axon towards
deeper layer
STELLATE
F
U
S
I
F
O
R
M

24. •Horizontal cells of Cajal
–Spindle shaped
–Parallel to the surface
–Internuncial type

•Cell of Mortinotti
–Small triangular cells
–Axons goes towards
surface

•Golgi type II
–Process ends close to
cell body
–Local circuit
CAJAL
MORTINOTTI
GOLGI

25. Layers of cerebral cortex
•Outer Molecular layer
–Horizontal cells + Golgi type II
–Tangential nerve fibers from
pyramidal, fusiform and cells of
Mortinotti

•Outer granular layer
–Small pyramidal cells + stellate
cells
–Dendrites end in first layer
–Axons forms association

•Outer pyramidal layer
–Medium and large pyramidal cells
–Axons forms association and
commissural fibers

OM
OP
OG

26. •Inner granular layer
–Packed stellate cells
–Lot of fibers as band-
Outer band of Baillarger

•Inner pyramidal/ganglion
–Large Betz cells
–Axons continues as
projection fibers
–Horizontal fibers forms
inner band of Baillarger

•Multiform layer/fusiform
cells
–Spindle shaped cells
–Granular, fusiform and
stellate type
Outer band
Inner band

27. Molecular layer
Outer granular layer
Outer pyramidal layer
Inner granular layer
Inner pyramidal layer
Pleomorphic layer
Pyramidal neuron

28. Cerebrum-cortex
G