PSYC 494N1 Lecture Notes - Ventral Lateral Nucleus, Pyramidal Cell, Motor Neuron

• School: McGill University
• Department: Psychology
• Course: PSYC 494N1
• Professor: Geraldine Akman

Document Summary

The initiation of movement by primary motor cortex. Sma is heavily interconnected with m1, cortical area 4. Stimulation intensities that are unable to evoke movement in other cortical areas are still effective in evoking movement when applied to area 4. Thus area 4 has dense, strong synaptic connections with the motor neurons and the spinal interneurons that drive them. Focal electrical stimulation of area 4 evokes the contraction of small groups of muscles and the somatic musculature is mapped systematically. The ribbon of cortex that stretches the full length of the precentral gyrus called the motor strip. The pathway by which motor cortex activates lower motor neurons originates in cortical layer v which has a population of pyramidal neurons. The layer v pyramidal cells in m1 receive their inputs primarily from two sources: Other cortical areas which originate in areas adjacent to area 4: area 6 and areas and 3, 1, and 2 (see fig.