Basal Ganglia Flashcards
(43 cards)
what 3 components make up the basal ganglia?
- corpus striatum
- amygdaloid nucleus
- claustrum
which structures are closely related to the basal ganglia?
- subthalamic nuclei (from diencephalon)
- substantia nigra (from midbrain)
- red nucleus
note: not anatomically related
what is the role of the basal nuclei?
important role in control of posture and voluntary movement
what makes up the corpus striatum?
caudate nucleus and lentiform nucleus
note: divided by internal capsule
what makes up the striatum (neostriatum)?
caudate nucleus and putamen
note: head of caudate is continuous with putamen of lentiform nucleus
caudate nucleus lies medial to the thalamus. T or F.
F
lies lateral
head of the caudate forms the lateral wall of the anterior horn of the lateral ventricle. T or F.
T
the tail of the caudate nucleus terminates anteriorly in the amygdaloid nucleus. T or F.
T
lentiform nucleus separates the caudate nucleus from the thalamus. T or F.
T
what makes up the lentiform nucleus?
putamen and globus pallidus
whats the function of the amygdaloid nucleus?
it can influence the bodys response to environmental changes eg if you sense fear it can increase ur heart rate, blood pressure etc.
what are the main sites for receiving input to the basal nuclei?
caudate nucleus and putamen
the basal ganglia receives no direct input from or output to the spinal cord. T or F.
T
what are the corpus striatum afferent fibers?
- corticostriate fibers
- thalamostriate fibers
- nigrostriatal fibers
- brainstem striatal fibers
where does the corticostriate fibers come from and go?
axons from all parts of cerebral cortex to the caudate nucleus and putamen
note: largest input is from the sensory motor cortex
what is the neurotransmitter of the corticostriate fibers?
Glutamate
what are the corpus striatum efferent fibers?
striatopallidal and striatonigral fibers
chorea, athetosis and ballism are examples of what kind of kinetic disorders?
hyperkinetic
what is huntington disease?
Autosomal dominant disease with choreiform movements and progressive dementia.
GABA, substance P and ACH neurons of the striatonigral inhibitory pathway degenerate. As a result the dopamine neurons of the substantia nigra dominate. Thus the nigrostriatal pathway inhibits the caudate and putamen
what is sydenham chorea?
Rapid, irregular, involuntary movements of the limbs, face and trunk occur. This condition is associated with rheumatic fever and antibodies form against the basal ganglia neurons.
what is hemiballismus?
Involuntary movement confined to one side of the body. The lesion is usually a small stroke occurring in the opposite subthalamic nuclei
what is parkinson disease?
Associated with neuronal degeneration in the substantia nigra. Results in a reduction in the release of dopamine which leads to hypersensitivity of the dopamine receptors in the post synaptic neurons in the striatum.
what are the characteristic signs and symptoms of parkinsons
tremor
rigidity
bradykinesis
postural disturbances
what are the globus pallidus afferent fibers?
Striatopallidal fibers
