Module 6 Page 1
The Cerebral Cortex and Our Divided Brain
Cerebral Cortex - the intricate fabric of interconnected neural cells covering the cerebral hemispheres;
the body's ultimate control and information-processing center. 20-23 billion nerve cells and 300 trillion
Structure of the Cortex
Glial Cells - 9X as many cells, Cells in the nervous system that support, nourish, and protect neurons;
they may also play a role in learning and thinking. (Einstein's brain found a greater concentration of glial
Frontal Lobes - portion of the cerebral cortex lying just behind the forehead; involved in speaking and
muscle movements and in making plans and judgments.
Parietal Lobes - portion of the cerebral cortex lying at the top of the head and toward the rear; receives
sensory input for touch and body position.
Occipital Lobes - portion of the cerebral cortex lying at the back of the head; includes areas that receive
information from the visual fields.
Temporal Lobes - portion of the cerebral cortex lying roughly above the ears; includes the auditory
areas, each receiving information primarily from the opposite ear.
Functions of the Cortex: Motor Functions
Motor Cortex - an area at the rear of the frontal lobes that controls voluntary movements. Fingers &
mouth require the greatest amount of cortical space.
Jose Delgado stimulated a spot on a patients motor cortex triggering his right hand to make a fist, who
despite the patients best efforts to keep his fingers open, had closed his hand.
Sensory Cortex - area at the front of the parietal lobes that registers and processes body touch and
movement sensations. The more sensitive the body region, the larger the sensory cortex area devoted
to it Ex. Lips.
Association Areas - areas of the cerebral cortex that are not involved in primary motor or sensory