Motor Disorders Flashcards
What are the causes of cerebellar lesions?
Stroke
Tumour
Congenital malformations
What are the signs and symptoms of lesions of the vermis of the cerebellum?
Truncal ataxia
Abnormal gait
What is a complication of a lesion of the vermis of the cerebellum?
Lesion may extend outwards
Compresses the fourth ventricle leading to hydrocephalus
A lesion in the left side of the cerebellum causes signs and symptoms in what side of the body?
Left side of the body
What are the signs and symptoms of a cerebellar lesion?
Dysdiadochokinesia
Ataxia
Nystagmus
Intention tremor
Slurred speech
Hypotonia
What is dysdiadochokinesia?
Impaired ability to perform rapid alternating movements
What is ataxia?
Lack of co-ordination of muscle movements
What is nystagmus?
Repetitive uncontrolled movements of the eyes
What is an intention tremor?
Tremor during visually guided and deliberate movements
What are the different basal ganglia disorders?
Parkinson’s disease
Huntington’s disease
Hemiballismus
How is the basal ganglia affected in Parkinson’s disease?
Death of substantia nigra pars compacta dopaminergic neurones
How are the direct and indirect pathways of the basal ganglia affected in Parkinson’s disease?
Direct pathway gives reduced excitation of cortex
Indirect pathway gives inhibition of cortex
What are the signs and symptoms of Parkinson’s disease?
Bradykinesia, slow movements
Resting tremor, disappears with active movement
Shuffling gait
Hypertonia
Hypophonia, reduced tone of voice
Reduced facial expression
Micrographia
Dementia
Depression
What is micrographia?
Handwriting becomes smaller over time
Parkinson’s disease affecting the right basal ganglia causes signs and symptoms in what side of the body?
Left side
Basal ganglia communicates with cortex on same side
But cortex controls other side of body
How is the basal ganglia affected in Huntington’s disease?
Death of neurones in the striatum
that project to the globus pallidus externa
How are the direct and indirect pathways of the basal ganglia affected in Huntington’s disease?
Direct pathway is unaffected
Indirect pathway gives excitation of the cortex of instead
What are the signs and symptoms of Huntington’s disease?
Chorea
Dystonia
Cognitive decline
Behavioural difficulties
What is chorea?
Involuntary jerky movements
What is dystonia?
Abnormal movements to do with repetitive or sustained muscle contractions
What are the signs and symptoms of more advanced Huntington’s disease? Why?
Paucity
Due to the direct pathway becoming affected too
How is the basal ganglia affected in hemiballismus?
Damage to subthalamic nucleus
How are the direct and indirect pathways affected in hemiballismus?
Direct pathway is unaffected
Indirect pathway gives excitation of cortex instead
What are the signs and symptoms of hemiballismus?
Abnormal large-amplitude movements
What usually causes hemiballismus?
Sub-cortical lacunar stroke
