Question

In regards to the spinothalamic tract, where does the second order neuron cross the midline?
a. at that spinal cord segment
b. in the brainstem
c. at the thalamus
d. never crosses midline

Answer 1

Answer:

The correct answer will be option A.

Explanation:

In spinothalamic tract is a projection with axons which terminates in the thalamic nuclei.  This tract comprises of three neuron pathways: primary order neurons, secondary order neurons and tertiary order neurons.

The axons of the secondary order neurons receive the impulse to form the primary order neuron in the dorsal neuron and then crosses the midline at the anterior spinal cord in ventral white commissure to reach the opposite sides. after this neuron passes through the brainstem to the thalamus.

Thus, option A- at that spinal cord segment is the correct answer.