Hyperkinetic
dysartHria
Dysfunction in the basal ganglia and
their major pathways
•Hyperkinetic dysarthria implies
pathologies in the basal ganglia, related
portion of the extrapyramidal system, or
sometimes the cerebellar control circuit.
•The diversity of lesion associated with
hyperkinetic dysarthria (and movement
disorder in general) reflects the diversity of
abnormal movements that may occur in
CNS disease and our limited understanding
of their anatomy and pathophysiology.
What causes hyperkinetic
movement
•An imbalance of either dopamine or
acetylcholine in the basal ganglia
•Chorea: As dancelike, because the movements
appear to be smooth and coordinated, but they
are actually unpredictable and purposeless
Some of the known disorders that cause
of chorea
a. Sydenham’s Chorea / chorea minor
b. Stroke
c. Tardive Dyskinesia
d. Anoxia
e. Carbon Monoxide
•Characteristics of Sydenham’s Chorea
1. Rare disorder that affects children between
5 and 15
2. Called St. Vitus Dance
3. Associated with rheumatic fever
4. May be caused by hypersensitive dopamine
receptors or too much dopamine
5. 40% of children exhibit hyperkinetic.
6. Usually disappears in 3-4 mo. w/o TX
•Chorea in stroke
a. Hemichorea because the involuntary
movements occur only on the contralateral
side of the body to the site of lesion (if damage
is restricted to only one side of the brain
usually affecting the basal ganglia or
thalamus)
•Chorea in stroke
b. Hemiballism (caused by damage to the
subthalamic nucleus near the substantia
nigra) characterized by wild and violent
involuntary movements of the limbs
contralateral to the lesion; usually remit
spontaneously after a period of days—months;
can be treated successfully with meds
•Tardive dyskinesia
a. Means late appearing involuntary
movements
b. Can cause choreic movement to the face,
mouth, and neck; lip smacking, tongue
protrusions, chewing motions and grimacing
c. Caused by taking antipsychotic
d. Women and elderly are more susceptible
Factors causing speech errors in chorea
a. Chorea can affect many different muscle
groups. The voluntary movement of all the
muscles are susceptible to interference from
the involuntary movements so all of the
processes of speech are affected. (This is in
contrast to other dysarthria where one or two
processes are primarily affected)
b. The movements are unpredictable and
variable. For instance one minute the muscles
of the lips and tongue may be affected, the
next, the respiratory muscles may be affected
or all could be affected at once or little
interference from choreic movements
Speech errors that are most evident in
individuals with chorea
Prolonged intervals between syllables and words
Variable rate of speech
Inappropriate silences
Excessive loudness variations
Prolonged phonemes
Rapid, brief inhalations or exhalations of air
Voice stoppages
Intermittent breathy voice quality
Speech characteristics in chorea
Prosody (may be primarily compensatory in
nature)
a. Prolonged intervals between syllables
(waiting for choreic movement to end)
b. variable rate of speech (hurrying before
next choreic movement begins)
c. others: monopitch, inappropriate
silences and monoloudness
Articulation errors
•Imprecise consonants: and distorted vowels:
result of involuntary choreic movements on
voluntary movements of articulation
•Prolongation of phonemes: choreic movements
that force the holding of an articulatory
position longer than normally required
Phonation problems
a. Harsh vocal quality
b. Breathy
c. Excess loudness variations
d. Strained-strangled vocal quality
e. Voice stoppages
May be caused by intermittent, involuntary
hyperadduction of the vf or intermittent vf
abductions (variability of the movements)
Respiratory difficulties
•Unexpected inhalations and exhalations of air
caused by involuntary movements of the chest
or diaphragm
•They can cause: extraneous phonations,
halting utterances, and short phrases and
excessive loudness variations (caused by
sudden increases in subglottic air pressure and
involuntary exhalations during phonation)
Resonance difficulties
•Involuntary movements that alter the timing
of velar elevation
Myoclonus
a. Involuntary and brief contractions of a
part of a muscle, a whole muscle or a group of
muscles in the same area of the body. The
contractions may occur singly, or in a
repeating irregular pattern or rhythmically
b. It can be found in cases of many medical
conditions: kidney failure, epilepsy, anoxia,
strokes, TBI, Alzheimer
Focal myoclonus (specific muscles or body parts
affected)
a. Hemifacial spasm (spasms around the eye
then spread to the entire face). It is a common
disorder and is painless but causes
embarrassment
b. Palatopharyngolaryngeal myoclonus:
• Rare; the contractions are fairly rhythmic
and occur about 1-3 times a second: 1-
3Hz
• Typical causes : brainstem strokes,
cerebellar lesions, encephalitis, and
tumors
Tic disorder
a. A tic is a rapid movement that can be
controlled voluntarily for a certain period of
time but is eventually performed because of
compulsive desire to do so
b. There are motor (eye blinking and complex
hand gestures and body movements: jumping,
kicking) and vocal tics (throat clearing,
shouting)
c. Stress increases frequency of tic
d. Etiology: mild brain damage, toxic
reactions, but no identifiable CNS
disorder in most cases
e. Idiopathic tics occur in about 10-12% of
the children in the form of excessive
eyeblinks for less than a month to about
one year, after which most disappear
Gilles de la Tourette syndrome
a. the development of symptoms before age 14
b. the slow appearance and disappearance of
symptoms
c. tic behaviors that change and evolve over
time
e. minor neurological abnormalities.
f. Causes: supersensitive dopamine receptors
in the striatum
g. genetic link; all show symptoms by age
10; prevalence 3/100,000; boys more
affected
h. vocal tics include
Essential tremor (organic tremor) sometimes
called familial tremor is
a progressive neurological disorder of which the
most recognizable feature is a tremor of
the arms or hands that is apparent during
voluntary movements such as eating and writing)
Essential tremor
•a. Most common hyperkinetic
movement disorder (300/100,000)
b. Benign movement disorder that
begins as a tremulous movement;
action tremor affected by stress and
fatigue; progression is slow
c. Appears to be idiopathic; beginning at
age 40-50; genetic
d. Mostly affects hands, arms, or head;
e. has been associated with Hemifacial spasm
and focal dystonia
Describe essential voice tremor
a. occurs in about 20% of the individuals with
essential tremor
b. characterized by a tremulous shaky vocal
quality caused by rhythmic, involuntary
contractions of the vf (6Hz), along with
vertical laryngeal movements
c. Primarily evident with vowel prolongation
d. Tremor of the lips, tongue or neck may
accompany the tremor; may slow down speech
in severe cases
Dystonia
a. Abnormal muscle tone causing
involuntary, prolonged muscle contractions
that interfere with normal movement or
posture; may affect a single group of muscles
or multiple groups
b. Movement is more sustained and slower
than chorea
c. Dystonia is not necessarily constant
and may appear/disappear during a
movement (waxing and waning). Severe
cases: contractions can be constant
resulting in painful, fixed contractions
of affected body part
Etiologies of Conditions where dystonia
is the primary symptom
a. Spasmodic torticollis: characterized by
intermittent (sometimes no contraction is
evident) dystonic contractions of the neck
muscles which result in an involuntary turning
of the head; the head also usually tilts upward
as a result of the contractions; stress and
anxiety affects frequency; speech is slow in
rate, mildly reduced in intelligibility and lower
in pitch for females
b. Drug induced dystonia (tardive dystonia):
chronic drug-induced dystonia (neuroleptic).
Withdrawal of the drug may stop dystonia
and Contractions appear near mouth and
face: grimacing, tongue protrusions;
sometimes generalizing to other body parts
c. Meige’s syndrome: Rare idiopathic
disease; characterized by repetitive eye
blinking and abnormal facial movement that
are often dystonic in nature.
it appears in early middle age and gets
progressively worse such that functional vision
is impossible.
When the jaw, tongue, mouth and neck are
sufficiently strong they cause hyperkinetic.
d. Spasmodic dysphonia: Not always classified as a
dystonia (sometime essential tremor); characterized
by involuntary vocal fold movements during
phonation. Unlike focal dystonia SD does not have a
gradual waxing and waning but are vigorous and
active
Expressed as adductor (vocal folds either constantly
adducted giving a strained quality or intermittently
giving a jerky tight quality or a shaky quality) or
abductor vocal folds are involuntarily abducted
resulting in moments of breathiness or aphonia
•Etiology is unknown but it is thought to be
related to BG disorder. Interesting feature is
normal voice for nonlinguistic phonation
[laughing, crying and unemotional (talking to
children and pets)/emotionally charged
vocalizations]
d. Types of dystonia (characterized according
to number of affected body parts)
a. Focal (only one body part: tongue, arm or
hand)
b. Segmental: affects two or more body parts
(neck, larynx, soft palate, jaw and face
c. Generalized dystonia: affects all four limbs
and torso or neck
d. Hemidystonia affects two or more body
parts on the same side of the body
How can we distinguish speech
characteristics of dystonia from chorea?
•More errors of
articulation in
dystonia than in
chorea
•Imprecise
consonants,
distorted vowels and
irregular
articulatory
breakdown
•Chorea displayed
more prosodic
errors than those
with dystonia
•Generally dystonia
had more
articulatory
problems and chorea
has more prosodic
errors
speech errors in dystonia
a. Articulation: imprecise consonants,
distorted vowels, irregular articulatory
breakdowns and prolonged phonems due to
sustained dystonic contractions o the oral
muscles
Irregularity of the breakdowns due to the
intermittent nature of dystonia; when the
contractions are absent articulation will
appear normal
b. Prosody: monopitch, monoloudness,
inappropriate silences and short phrases;
reduced stress in normally stressed words and
syllables; due to dystonic muscular
contractions of the vocal tract that reduce the
range and speed of the laryngeal movements
Phonation: harsh vocal quality; strained-
strangled quality, increased muscle tone in the
larynx excessive loudness variations
(unpredictable waxing an waning quality of
dystonic contractions)
•Respiration: excessive loudness might be a
result of affected muscles of respiration. May
be caused by involuntary contractions or
compensatory behaviors for the abnormal
respiratory movements
•Resonance: may be present but if present is
very mild
What is the TX for hyperkinetic
dysarthria
Mostly medication that suppress the
involuntary movements
Choreic and tic: Haloperidol
Myoclonic jerks clonazepam or valproic
SD and spasmodic torticollis: Botox (most
effective)
Behavioral treatment on trial period for those not
too severely affected:
a. Locate sensory tricks
b. Relaxation therapy and related treatment
1. mental imagery
2. habit reversal
c. Bite blocks (focal dystonic jaw movements to
stabilize the jaw during speech (seems to suppress
dystonic jaw movements)
d. Easy onset of phonation for laryngeal
involuntary movements