The cerebrum or forebrain is the largest and major part of your brain. Of the twelve billion neurons contained in your brain, about 9 billion are found on the cerebrum, which located in the upper region of your brain. Nerve cells make up the gray surface of the cerebrum.
The surface of your cerebrum is called the cerebrum cortex. This protective covering is folded into ridges and depressions called convolutions. Remember the folds in your intestinal wall? Convolutions and these folds both serve the same function—that is to increase the surface area. The cerebral cortex of your brain controls many functions that are related to intelligence. You reason out, memorize, and become creative mainly because of the cerebral cortex.
Two hemispheres comprise your brain cerebrum. These two halves are joined to one another by tough nerves fibers or axons. It is through the axons that communication between the right and left hemisphere is possible. Each of the hemispheres in your cerebrum is divided into four lobes—the frontal, temporal, parietal, and occipital lobes.
f or e b Func t i ons i n t a s t er a i n a n d s me l lTemporal Learning and memoryParietal Touch and sensory inputOccipital Vision, motor output, speechFrontal Personality, thought, speech
Role of the Cerebrum Many activities are controlled by specific regions of the cerebrum. The motor areas control the muscles, particularly those found in the face, tongue, neck, shoulders, arms, trunk, and legs. The vision center of the occipital lobe interprets what you see with your eyes. In the frontal lobe, you develop emotions, judgment, will power, and self-control. The things you see, hear, and feel are registered as impressions in the sensory areas. Your intellectual capacity is determined by the ability of the cerebral cortex to register impressions, the activity of the association areas, and the memory of past experiences.
Do you know why most of us are right handed? It is because messages from the left hemisphere of our cerebrum cross over the neurons that control the movements on the right side of our body and vice versa. Generally, one hemisphere of your brain is dominant over the other. In this case, the left hemisphere is usually dominant.
Have you met some paralyzed people who speak with a slur? Did you observe what side of the body was affected? In most people, an area in the left hemisphere controls speech. The left side of the brain deals with mathematics and logic and the right side is responsible for our artistic and musical talents.