Afferent or Sensory Neurons

Afferent or sensory neurons, the opposite of efferent (motor) neurons, carry external nerve impulses from the environment to the brain. They travel from sensory receptors in the tissues and sensory organs (eyes, ears, nose, tongue), as well as receptors for pain/temperature, balance/sense of where the body is in space — all of which make up the peripheral nervous system (PNS) — to the central nervous system (CNS). In the CNS, interneurons respond and communicate with efferent neurons sending impulses via the spinal cord out to the muscles, indicating what motion to perform. Also see Somatic/Visceral Afferents (conduct same process for body’s internal environment and organ system).