ANAT 312 Lecture Notes - Lecture 4: Supplementary Eye Field, Supplementary Motor Area, Basal Ganglia

• School: Queen's University
• Department: Anatomy and Cell Biology
• Course: ANAT 312
• Professor: Leslie W Mac Kenzie

Document Summary

Parkinsons disease hypokinetic symptoms: mask like expression, pill rolling tremor, flexion of trunk, slow, shuffling gate. Huntington"s disease hyperkinetic symptoms: twitching movements of the head, grimacing movements in the face, tongue and lips, gesticulating/jerking and movements of the limbs. The gpi is always firing tonicly unless stimulated which keeps down thalamus activity. Projections from snpc to putamen are excitatory (d1 neurons) which stimulates the direct pathway which allows for passive movement. D2 pathway is inhibitory control and scale back movements. There is a constant balance between the direct (excitatory) and indirect (inhibitory) pathways. Parkinsons disease loss of da from snpc. Decrease in the direct pathway and increase in the indirect pathway. Results in dystonia and rigidity, tremor at rest (due to cell oscillations in bg), increased muscle tone, loss of postural reflexes and loss of eye saccades. The loss of da affects the executive motor function pathway but involuntary movements can still be accomplished!