Which of the following is NOT true of corticospinal fibers?
A)They may synapse directly on alpha motor neurons.
B)They may synapse directly on gamma motor neurons.
C)They may synapse directly on interneurons.
D)They are collectively sometimes called the extrapyramidal system.
E)They may synapse with afferent neurons in ascending pathways.

Question

Quizplus · Accepted Answer

Corticospinal fibers are not collectively referred to as the extrapyramidal system. The extrapyramidal system consists of other motor pathways that originate in the basal ganglia and other subcortical structures, but not in the cortex. Corticospinal fibers are part of the pyramidal system, which consists of motor pathways that originate in the cerebral cortex and descend through the medulla oblongata. Choices A, B, C, and E are true statements about corticospinal fibers.

Which of the Following Is NOT True of Corticospinal Fibers