When scientists first examined the human brain, they found it to be divided into two halves, or hemispheres, which are nearly identical in appearance, mirroring each other just as the two sides of the body do. When Roger Sperry examined patients whose connection between the two hemispheres- the corpus callosum- was served, he found that the two sides of the brain seemed to have different functions. Many investigators have studied the differences between the functions of the two hemispheres and found their relationship to be quite complex. Unfortunately, however, most people have tended to over generalize. The left brain is suppose to be logical, rational and analytical, whereas the right brain is supposed to be creative and emotional. The brain's hemispheres are not simplistically split into two neat divisions. In fact, both halves of the brain participate in almost all our mental activity.To begin with, both sides of the brain are in operation when we reason. The left brain seems to dominate in the kind of reasoning it takes to translate symbols, recognize abstract differences, and handle algebra and geometry problems. The left hemisphere may be dominant in these types of reasoning. The right hemisphere also reasons. The right half functions to integrate information and draw conclusions. The left hemisphere is dominant in recognizing abstract differences. The right hemisphere tends to recognize sameness. For example, the right side is where we mediate facial recognition and recognize shapes.
The two hemispheres act as partners in language and communication. It appears that the left hemisphere is dominant when it comes to understanding grammar and syntax, but when it comes to interpreting emotions in communication, the right brain excels. The right brain can interpret tone of voice and facial expressions. Whenever we use language, both sides of the brain process the information.The brain is not totally divided about music. Many people assume that music is mediated solely in the right brain. That is not so. It is true that the right brain recognizes chords and melodies and seems to mediate pure and slow tones.The left hemisphere is involved in music. Fast music, such as bluegrass, requires judgments about sequencing and rhythm, and for this the left hemisphere lends it services. When words are involved, again the left brain dominates.Both halves of the brain are involved in our mental activities. The corpus callosum and other bridges between the two hemispheres obviously serve to integrate the functions of the two halves, which are in constant communication to make sense out of life.