The Human brain depends on the ability of the neurons to relay electrochemical signals to other cells and the ability to respond from them. In the earliest stages of development, there is a close relation between structure and function. However, with time the functions become independently with the structures. In addition, sensory and motor development is a process by which an individual gains, uses, and coordination of the larger muscles legs, trunk, arms, and the smaller muscles of the hands. For instance, a baby begins to acquire new awareness through touch, sight, smell and hearing.