In pain pathways, which neuron is responsible for relay and crossing within the spinal cord?

In pain pathways, which neuron is responsible for relay and crossing within the spinal cord?

• A. First Order Neuron
• B. Third Order Neuron
• C. Second Order Neuron
• D. Fourth Order Neuron

Answer: (C)

In pain transmission, the signal from nociceptors first arrives at the dorsal horn via the primary (first-order) neuron. The crucial step that allows pain information to reach the brain is performed by the second-order neuron: it receives the signal in the dorsal horn, decussates (crosses) to the opposite side of the spinal cord at the ventral white commissure, and then ascends in the contralateral spinothalamic tract toward the thalamus. From there, a third-order neuron carries the information from the thalamus to the primary somatosensory cortex for conscious perception. The notion of a fourth-order neuron isn’t part of the standard pain pathway. So the neuron responsible for relay and crossing within the spinal cord is the second-order neuron.

In pain transmission, the signal from nociceptors first arrives at the dorsal horn via the primary (first-order) neuron. The crucial step that allows pain information to reach the brain is performed by the second-order neuron: it receives the signal in the dorsal horn, decussates (crosses) to the opposite side of the spinal cord at the ventral white commissure, and then ascends in the contralateral spinothalamic tract toward the thalamus. From there, a third-order neuron carries the information from the thalamus to the primary somatosensory cortex for conscious perception. The notion of a fourth-order neuron isn’t part of the standard pain pathway. So the neuron responsible for relay and crossing within the spinal cord is the second-order neuron.