Brain. Gross clinical specimen of a human brain seen from above, with the front of the brain at left. The brain is the nerve centre controlling bodily function and thought. It interprets nerve signals from the body and initiates appropriate responses. Most of the visible surface consists of the folds (sulci) of the cerebral cortex, the area responsible for conscious movement, language and memory. The brain is divided into two hemispheres. Motor functions for one side of the body are dealt with by the opposing hemisphere. Sensory input is also switched to the opposing hemisphere. The hemispheres are connected by a thick band of nerve fibres called the corpus callosum (not seen).