What are the masses of gray matter that lie deep within the cerebral hemispheres and that are responsible for regulating intensity and precision of voluntary movement

Cerebral cortex.

Explanation:

The masses of gray matter that lie deep within the cerebral hemispheres is called cerebral cortex. The cerebral cortex is responsible for many brain functions such as sensation, perception, memory, association, thought, and voluntary physical action. Damage occur to cerebral cortex can leads to many cognitive, sensory, and emotional difficulties in the body. It is also responsible for regulating intensity and precision of voluntary movement.

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