NRSC 277 Lecture Notes - Lecture 21: Basal Ganglia, Subthalamic Nucleus, Supplementary Motor Area
Document Summary
Basal ganglia: involved in the selection and initiation of willed movements. Group of neurons wrapped around the cerebral cortex. Direct motor pathway - (cid:335)the pyra id pathway(cid:336) Corticospinal tract, rubrospinal tract, reticulospinal tracts, etc. Both cerebellum and bg - do not send out motor command; indirect motor pathways. Cerebellum: involved in making motor movement more smooth; maintain balance and posture; coordinate eye and head movement; help to plan the sequential movement. Bg: involved in the selection of the movement and the initiation of the voluntary movement. Cerebellum lesions: symptoms are in the ipsilateral side of the body. Hypotonia, dysmetria, giant gait, tremors in action, scanned speech. Bg lesions: symptoms are in the contralateral side of the body. Unwanted movement, increased muscle tones that cause rigidity, tremors at rest, dyskinesia during rest, small and shuffling gait, hemiballistic movement. In some cases, bg lesions can also cause muscle tone to decrease. Striatum (or neostriatum) = caudate + putamen.
