Question

the gate - control theory of pain suggests:

• pain signals are only processed in the brain.
• pain signals travel through a single pathway to the brain.
• the brain can open or close gates to modify pain perception.
• pain is intensified by endorphins.

Explanation:

The gate-control theory of pain proposes that there are "gates" in the spinal cord (regulated by signals from the brain and other nerve fibers) that can open or close, which affects how much pain signal reaches the brain, thereby modifying pain perception. The other options are incorrect: pain signals are processed in the spinal cord as well as the brain, they travel through multiple pathways, and endorphins reduce pain perception, not intensify it.

Answer:

The brain can open or close gates to modify pain perception.