Question

Direct stimulation of the motor cortex would be most likely to result in

A. feelings of anger
B. acceleration of heartbeat
C. a sensation of being touched on the arm
D. movement of the mouth and lips
E. intense pain

Answer 1

Direct stimulation of the motor cortex is most likely to result in movement of the mouth and lips due to the primary motor cortex's role in planning and initiating voluntary muscle movements.

Step-by-step explanation:

Direct stimulation of the motor cortex would be most likely to result in movement of the mouth and lips. The motor cortex, especially the precentral gyrus of the frontal lobe, is known for its role in planning and executing voluntary muscle movements. Neurosurgeon Walter Penfield's pioneering work involved stimulating the motor cortex while patients were under local anesthesia and observing their responses. He discovered that stimulation of specific areas of the cortex led to muscle movement in corresponding parts of the body. This is supported by our understanding that the primary motor cortex receives input for movement planning and its output via the spinal cord neurons initiates skeletal muscle contraction.