Final answer:
The loss of gray matter in the cerebral cortex is balanced by an increase in white matter.
Step-by-step explanation:
The loss of gray matter in the cerebral cortex is balanced by a steady increase in white matter. Gray matter, which contains cell bodies of neurons, is found in the outer cortex of the brain, while white matter consists of myelinated axons. Extensive folding in the cerebral cortex allows for more gray matter to fit into the limited space of the cranial cavity. If the gray matter of the cortex were laid out flat, its surface area would be roughly equal to one square meter.