Basal Ganglia Flashcards
The term ‘basal ganglia’ refers to the large, strongly interconnected _____ masses deep within the _____ ______, ________, and _____ that are instrumental in the _______ of _______ movements and the ______ of the _______ associated with ______ movements
The term ‘basal ganglia’ refers to the large, strongly interconnected nuclear masses deep within the cerebral hemispheres, diencephalon, and midbrain that are instrumental in the initiation of voluntary movements and the control of the postural adjustments associated with voluntary movements.”
Patients with lesions in the basal ganglia have difficulty with _____ of movement (too slow or too fast), ____ or ____ movement, or they experience ____ movements.
Patients with lesions in the basal ganglia have difficulty with speed of movement (too slow or too fast), starting or stopping movement, or they experience unwanted movements.
The function of the cerebellum involves muscle ______ during ____ movements
coordination, voluntary
abnormal movement is known as _______?
dyskinesia
excessive and/or uncontrolled movements; involuntary movements (example: Huntington’s disease) is known as _____?
hyperkinesia
“paucity of movement;” difficulty starting movements, rigidity, slowness (example: Parkinson’s disease) is also known as ____?
hypokinesia
Aka a “resting tremor”
involuntary movement
The cerebrum is composed of what two parts?
Telencephalon + Diencephalon
Cerebral hemisphere is composed of what parts?
Telencephalon + Lateral Ventricles
The telencephalon is composed of what three parts?
Cerebral cortex + White Matter + Basal Nuclei
basal ganglia system includes nuclei from _____, ____, and _____
basal ganglia system includes nuclei from telencephalon, diencephalon, and midbrain
What are the three deep cerebral nuclei?
caudate, putamen, globus pallidus,
the deep cerebral nuclei are derived from what?
telencephalon
Besides the cerebral nuclei, what are two additional parts of the basal ganglia system?
substantia nigra and subthalamic nucleus
the substantia nigra is derived from the _____.
midbrain
the subthalamic nucleus is derived from the _____.
midbrain
The lenticular nucleus is composed of what deep cerebral nuclei?
globus pallidus and putamen
the striatum is composed of what two deep cerebral nuclei?
caudate and putamen
Know the anatomy of the basal ganglia
Is the amygdala part of the basal ganglia?
No! It is the reward center of the brain
What lobe is the putamen positioned closest to?
temporal lobe
globus pallidus lies ___ to the putamen
medial
______ lies between the putamen and the thalamus
internal capsule
_____ lies deep to the internal capsule
thalamus
What lies on the rostral most terminus of ventral horn of lateral ventricle?
amygdala
the _____ is closely associated with the _____, which is important for memory
the amygdala is closely associated with the hippocampus, which is important for memory
the caudate head is located on the ____ wall of the ____ horn of the ____ ventricle.
the caudate head is located on the lateral wall of the anterior horn of the lateral ventricle.
The tail of the caudate is found immediately ____ to the ___ horn of the ___ ventricle.
The tail of the caudate is found immediately rostral to the posterior horn of the lateral ventricle.
What are the three main sources of input from the basal ganglia to the striatum?
cerebral cortex, substantia pars compacta, and thalamus
Inputs from cerebral cortex and substantia nigra are most important for what kind of pathways?
motor pathways
the inputs from the basal ganglia to the striatum are all ___
excitatory
immediately deep to the subthalamic nucleus is the ___ ____
substantia nigra
Basal ganglia outputs of the striatum arise from ____ _____ ____ and ____ _____ _____ ______.
Basal ganglia outputs of the striatum arise from globus pallidus internus and substantia nigra pars reticulata
direct pathway: net effect = ???
excitatory
indirect pathway: net effect= ???
inhibition
double inhibition results in ____
disinhibition
What happens when an inhibitor inhibits the inhibitor?
disinhibition
Excitatory inputs use what neurotransmitter?
glutamate
inhibitory inputs use what neurotransmitter?
GABA
net effect of disinhibition: ____ fires and ____neuron takes off and goes to the ____ ____.
net effect of disinhibition: thalamus fires and excitatory neuron takes off and goes to the cerebral cortex
does disinhibition occur in one or both pathways?
both
For a DIRECT pathway, the net effect of disinhibition=_____ activity by _____ excitation of _____ ____
For a direct pathway, the net effect of disinhibition=INCREASED activity by increased excitation of cerebral cortex
In Direct pathway, Dopamine from SNc further ____ (via______)
In direct pathway, dopamine from SNc further excites (via D1 receptors)
In the INDIRECT pathway, disinhibition allows subthalamic nucleus to turn on the____ switch to thalamus
In the INDIRECT pathwat, disinhibition allows subthalamic nucleus to turn on the OFF switch to thalamus
In INDIRECT pathway, Dopamine from SNc ____ pathway (b/c ____)
In INDIRECT pathway, Dopamine from SNc slows pathway (b/c D2 receptors)
Example of HYPOkinesia
Parkinson’s disease
Example of HYPERkineasia
Huntington’s chorea
Example of dyskinesia
Hemiballismus
Patient manifestations in Parkinson’s:
______ (“paucity of movement”), _____ rigidity, resting (“____-____”) tremor, _____gait, depression, etc.
Patient manifestations in Parkinson’s:
Bradykinesia (“paucity of movement”), cogwheel rigidity, resting (“pill-rolling”) tremor, shuffling gait, depression, etc.
Parkinson’s neuroanatomy:
Loss of pigmented ______ neurons from substantia nigra ____ _____
Parkinson’s neuroanatomy:
Loss of pigmented dopaminergic neurons from substantia nigra pars compacta
Where is the Parkinson’s defect located?
substantia nigra pars compacta
Is parkinson’s a lesion of the direct or indirect pathway?
direct
Patient manifestations of Huntington’s (onset around ___ yrs):
____, _____, _____changes, dementia
Patient manifestations of Huntington’s (onset around 40 yrs):
Chorea, athetosis, personality changes, dementia
Neuroanatomy of Huntington’s:
Degeneration of ______ neurons in ____ leading to ____in ____of caudate nucleus and ____ of ventricles
Neuroanatomy of Huntington’s:
Degeneration of GABAergic neurons in striatum leading to atrophy in head of caudate nucleus and dilation of ventricles
The cause of Huntingon’s is an____ ____disorder, ____trinucleotide repeat
The cause of Huntingon’s is an autosomal dominant disorder, CAG trinucleotide repeat
Huntington disease affects the _____, specifically the ___ ____. It affects the _____ pathway.
Huntington disease affects the striatum, specifically the caudate nucleus. It affects the indirect pathway.
Hemiballismus:
- Patient manifestations: spontaneous, uncontrolled _____ movements of the ____
- Neuroanatomy: ____destruction of the _____subthalamic nucleus
- Causes: Chronic _____???
Hemiballismus:
- Patient manifestations: spontaneous, uncontrolled flinging movements of the limbs
- Neuroanatomy: Hemorrhagic destruction of the contralateral subthalamic nucleus
- Causes: Chronic hypertension???
