The brain then relays signals to the muscles in your hands and arms. ??? ??? ??? Cerebrum largest, most highly developed part of the brain, composed of 2 hemispheres and 4 lobes, responsible for functions such as Thinking, Perceiving, Motor Function, Planning and Organization, Touch Sensation ??? ??? ??? Synapse The tiny gap between neurons across which they communicate ??? ??? ??? Temporal Lobes