Define gray matter and white matter. State the locations and functions of the primary motor and somatosensory cortexes.

The Brain – the Homunculus
Purpose: The brain has a specific organization that is basically similar in all individuals. By knowledge of the location of specific areas in the cerebral cortex and nuclei in the brain one can predict the locations of diseases such as strokes, lesions, and so forth. We will compare the mapping of the motor cortex and the sensory cortex in this assignment.

By the end of this assignment you should be able to:
Define gray matter and white matter.
State the locations and functions of the primary motor and somatosensory cortexes.
Relate the mapping of the number of sensory receptors to the somatosensory cortex.
Relate the mapping of the number of motor neurons and motor units to the primary motor cortex.