Describe ipsilateral and contralateral projection in the human brain

Question

What will be an ideal response?

Answer 1

The cerebral cortex forms the outer layer of the two halves of the brain—the left and right cerebral hemispheres. Although the two hemispheres appear to be similar, they function differently. The left cerebral hemisphere is specialized for some kinds of activity, whereas the right cerebral hemisphere is specialized for other kinds. For example, receptors in the skin on the right side of the body generally send information through the medulla to areas in the left hemisphere in the brain. The receptors on the left side generally transmit information to the right hemisphere. Similarly, the left hemisphere of the brain directs the motor responses on the right side of the body. The right hemisphere directs responses on the left side of the body. Not all information transmission is contralateral—from one side to another. Some ipsilateral transmission—on the same side— occurs as well. For example, odor information from the right nostril goes primarily to the right side of the brain. About half the information from the right eye goes to the right side of the brain; the other half goes to the left side of the brain. In addition to this general tendency for contralateral specialization, the hemispheres also communicate directly with one another. The corpus callosum is a dense aggregate of neural fibers connecting the two cerebral hemispheres. It transmits information back and forth. Once information has reached one hemisphere, the corpus callosum transfers it to the other hemisphere. If the corpus callosum is cut, the two cerebral hemispheres cannot communicate with each other. Although some functioning, such as language, is highly lateralized, most functioning—even language—depends in large part on integration of the two hemispheres of the brain.