Final answer:
The median nerve is decompressed in a carpal tunnel release surgery to reduce the symptoms of carpal tunnel syndrome.
Step-by-step explanation:
The peripheral nerve that is decompressed in a carpal tunnel release is the median nerve. Carpal tunnel syndrome occurs when the median nerve in the wrist becomes compressed between the carpal bones. This compression can lead to pain, numbness, and tingling in the thumb and first two fingers of the hand. Surgery to cut the carpal ligament helps reduce pressure on the median nerve and is a more effective treatment than nonsurgical options.