The cerebral cortex is the layer of the brain often referred to as gray matter. The cortex (thin layer of tissue) is gray because nerves in this area lack the insulation that makes most other parts of the brain appear to be white. The cortex covers the outer portion (1.5mm to 5mm) of the cerebrum and cerebellum. The portion of the cortex that covers the cerebrum is called the cerebral cortex.
The cerebral cortex consists of folded bulges called gyri that create deep furrows or fissures called sulci. The folds in the brain add to its surface area and therefore increase the amount of gray matter and the quantity of information that can be processed.
The cerebral cortex is divided into right and left hemispheres. It encompasses about two-thirds of the brain mass and lies over and around most of the structures of the brain. It is the most highly developed part of the human brain and is responsible for thinking, perceiving, producing and understanding language. It is also the most recent structure in the history of brain evolution.
Most of the actual information processing in the brain takes place in the cerebral cortex. The cerebral cortex is divided into lobes that each have a specific function. For example, there are specific areas involved in vision, hearing, touch, movement, and smell. Other areas are critical for thinking and reasoning. Although many functions, such as touch, are found in both the right and left cerebral hemispheres, some functions are found in only one cerebral hemisphere. For example, in most people, language abilities are found in the left hemisphere.
Cerebral Cortex Lobes
Parietal Lobe - involved in the reception and processing of sensory information from the body.
Frontal Lobe - involved with decision-making, problem solving, and planning.
Occipital Lobe - involved with vision.
Temporal Lobe - involved with memory, emotion, hearing, and language.
In summary, the cerebral cortex is responsible for sensing and interpreting input from various sources and maintaining cognitive function. Sensory functions interpreted by the cerebral cortex include hearing, touch, and vision. Cognitive functions include thinking, perceiving, and understanding language. For additional information on the cerebral cortex visit the Cerebral Cortex and Cerebral Cortex Lobes pages.
*Portions of this material adapted from NIH Publication No.01-3440a and "Mind Over Matter" NIH Publication No. 00-3592.