Movement Disorders

Question 0

Upper Motor Neuron Disorders-Symptoms

Answer 0

Weakness in extensors of upper limbs and felxors of lwoer limbs
Spasticity
increased stretch reflexes
Babinski sign

Question 1

Upper Motor Neurons

Answer 1

Cell bodies in the cortex, axons to internal capsal and cross in the spinal cord
Parasaggital-legs
lateral-hands
lower lateral-face

Question 2

Lower Motor Nueron Disorders-symptoms

Answer 2

Weakness
REduced muscle bulk
Fasciculations (twitches)
REduced stretch reflexes

They are the peripheral or cranial nerves.

Question 3

Basal Ganglia

Answer 3

Motor dysfunction is in the striatum.

Output is the job od the globus pallidus.

Question 4

Movement Disorders: Basal Ganglia

Answer 4

Hypokinetic-syndromes characterized by impoverished voluntary movement
Hyperkinetic-syndromes characterized by abnormal involuntary movements.

Question 5

Hypokinetic Disorders

Answer 5

Bradykinesia-slowness
Akinesia-no movement
rigidity
akinetic-rigid syndromes
parkinsonism
increased tone in limbs whe passively moved

Question 6

Parkinsonism

Answer 6

Rest tremor
bradykinesia
Rigidity
Postural instability
Same symptoms as hypokinetic syndroms. 
Tremor stops with voluntary movement-visual input plays a major role

Question 7

Parkinson’s disease Pathology

Answer 7

Neuronal loss in the substantia nigra
nigrostrital projections
Neurotransmitter is dopamine

Question 8

Dopamine production

Answer 8

Tyrosine to DOPA to dopamine

continously formed from amino acids. Trapped in the presynaptic vessicle then interacts with post synaptic receptors.

Question 9

Parkinson Treatment

Answer 9

Levodopa as a precurosr to dopamine in order to cross the brain blood barrier.
Plasma Levodopa fluctuates but usually buffering th body limits this.
However, motor fluctuations occurs whn it depletes too quickly and can cause bradykenesia
At peak dosage, dyskensia can occur which is involuntary muscle movements (overdose at the peak basically)

Question 10

Treatment for Parkinsons-lesions

Answer 10

Leasion to internal global pallidus on other side of the body

Question 11

Deep Brian stimulation

Answer 11

If stumulated-turns that part off so stimulate subthalamic nucleus or internal global pallidus
combination of meds and stimulation is needed

Question 12

Extrapyramidal Disorders

Answer 12

Hypokinetic-syndomres characterized by impoverish voluntary movement
Hyperkinetic-syndromes characterized by abnormal involuntary movements

Question 13

Hyperkinetic

Answer 13

Tremor
Chorea
Ballismus
Dystonia
Myoclonus
Tics

Question 14

Tremor

Answer 14

Involuntary, rythmic, sinusoidal
Classified by:
relation to activity-rest, posteral, kinetic
Etiology:
Physiological, essential, parkinsonian, cerebellar

Question 15

Physiological Tremor

Answer 15

Common
Postural
Aggravated by stress, anxiety, caffeine, drugs

Question 16

Essetial Tremor

Answer 16

Common, often benign
posterual or kinetic tremor
aggravated by stress, anxiety, caffeine and drugs
Alcohol-responsive.
Action tremor
Deep brain stimulation to the ventral lateal nuceli thalamus to decrease disabling tremors

Question 17

Chorea

Answer 17

Irregular, unpredictable, purposeless, rapid movements that flow randomly from one body part to another
Related to Huntingtons

Question 18

Huntingtons Disease

Answer 18

Inherited neurodegenerative disorder
Autosomal dominant
100% penetrance
age of onset 35-45 years
100% heritability
Motor, cognition and behavioural dysfunction
Inexorably progressive-death 15-20 years after symptom onset
personality change and schizo associtation

Question 19

Huntingtons Clinical features

Answer 19

Motor dysfunction:
-chorea is usually the earliest sign. initially in the fingers, toes and face and it is progressive
-dystonia and parkinsonian features later
-progressive incoordination, unsteadiness, immonbility, dysarthria, dysphagia
Cognitive Impairment:
-some degree is inevitable
-occasionally minimal
Behavioural Disorders:
-gradual change in personality
-affective disorders in 30-40%
-schizophrenia and other psychoses in 10%
-high suicidal risk

Question 20

Huntingtons Neurobiology

Answer 20

Shrunken head of caudate nucleus
Expanded ventricles
Thinned Cortex
Loss of tissue means a loss of neurons

Question 21

Huntingtons Genetics

Answer 21

Short arm tip of chromosome 4
Autosomal dominant
Very low spontaneous mutation rate
IT15 gene-everyone has this protein and it is needed for life/brain development. normally there is  5-35 (CAG) repeat
40-240 repeat gives you Huntingtons
More repeats means an earlier onset

Question 22

Huntingtin

Answer 22

Transgenic mouse:
reduced levels associated with aberrant brain development and perinatal lethality
-normal levels, even of mutant huntingtin is required for normal brain development
Critcal role in neurogenesis

Question 23

Huntington’s treatment

Answer 23

No known treatemnt effective at altering disease progression

Question 24

Ballismus

Answer 24

Large amplitude, violent, flinging movements in proximal muscle groups, typically unilateral
Hemiballismus: subthalamic nucleus stroke

Question 25

Dystonia

Answer 25

Sustained muscle contraction, often giving ride to twisting, repetitive movements or to sustained postures
idiopathic (genetic?), inherited disorders of metabolism, focal basal ganglia lesions-stroke of the basal ganglia.
1. Focal-muscle contraction causing postoral abnormality.
2. Task-specific-whem brain has put effort into learning and professionalizing a task
3. Generalized-early onset with DYT1 mutation. Surgery to stimulate the internal globus pallidus bilaterally.