Increases in cortical thickness in the hand area of the primary motor cortex are associated with increases in:

A) hand size.
B) grip strength.
C) manual dexterity.
D) tendon brittleness.

Cortical Thickness

A measure of the thickness of the cerebral cortex, the brain's outer layer, often associated with cognitive abilities.

Primary Motor Cortex

The zone in the cerebral cortex engaged in the design, regulation, and enactment of movements made voluntarily.