The Basal Nuclei And Motor Control Flashcards
What are the basal nuclei
A collection of nuclei deep to the white matter of cerebral cortex
Also called cerebral nuclei
Masses of gray matter
Are embedded in white matter
What are the basal nuclei composed of
Caudate nucleus
Putamen
Globus pallidus
Subthalamic nucleus
Substantia Nigra
Much of the output of the basal nuclei which is mediated through the …… is to ….. the …… to the cerebral cortex
Thalamus is to reduce or dampen the excitatory input to the cerebral cortex
The basal nuclei provide a …….. off which ….. can be made
Postural platform off which purposeful movement can be made
When discharge patterns of BN are excessive, there is…
An abnormal slowing of movements
If there is a reduced output….
Abnormal involuntary movements occur at periods of rest (dyskinesia)
Basal nuceli encode for
Decision to move, direction of movement, amplitude of movement, motor expression of emotions
Input to the basal nuclei
Input to the striatum
Putamen - micromary motor area, secondary motor areas primary somatosensory area
Caudate nucleus - association areas, frontal eye fields, limbic system
Input enables…
BN to integrate info from multiple sources
Out put from the basal nuclei
Output from the globus pallidus interna (medial)
Via GABA-ergic neurons
To the thalamus
Thalamus under tonic inhibiton
Overall output from thalamus is excitatory to the cortex
Strength of thalamic signal dependent on GPi
Output from BN is …
Highly regulated
Balance of ……. To the thalamus
Inhibitory and excitatory pathways to the thalamus
Thalamus is under …… and BN either ……
Tonic inhibiton and basal nuclei either increase or decrease this inhibiton
Caudate nucleus
GABA - inhibitory
Putamen
GABA - inhibitory