<P> Physiologically , the function of the brain is to exert centralized control over the other organs of the body . The brain acts on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones . This centralized control allows rapid and coordinated responses to changes in the environment . Some basic types of responsiveness such as reflexes can be mediated by the spinal cord or peripheral ganglia , but sophisticated purposeful control of behavior based on complex sensory input requires the information integrating capabilities of a centralized brain . </P>
what is the main purpose of the brain
to exert centralized control over the other organs of the body