Most axons of the dorsolateral corticorubrospinal tract synapse on
A) muscles of the fingers and thumb.
B) muscles of the hands and wrists.
C) interneurons of the spinal gray matter that in turn synapse on motor neurons that project to the distal muscles of the arms and legs.
D) motor neurons that project to the hands.
E) Betz cells.

Question

Quizplus · Accepted Answer

The dorsolateral corticorubrospinal tract, also known as the lateral corticospinal tract, originates in the motor cortex and travels down through the brainstem and spinal cord. Most of the axons of this tract synapse on interneurons in the spinal gray matter, which in turn synapse on motor neurons that project to the distal muscles of the arms and legs. Therefore, choice C is the best answer as it correctly describes where the axons of this tract synapse. Choices A, B, D, and E are incorrect as they describe synapses on specific muscles or neurons, which may not be representative of the majority of axonal connections in this tract.

Most Axons of the Dorsolateral Corticorubrospinal Tract Synapse on