Sensor or afferent neurons convey information from tissues and organs to the brain, and efferent signals transmit information from the brain to effector cells in the body.

Sensory afferent neurons convey information from tissues and organs into the CNS (central nervous system), while efferent neurons transmit signals from the central nervous system to the effector cells. Interneurons connect neurons within specific regions of the central nervous system. Afferent and efferent can also refer generally to neurons, which, respectively, bring information to or send information from the brain region.

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Key Points

• Afferent neurons convey information from tissues and organs to the brain.

• Efferent neurons signals transmit information from the brain to effector cells in the body; they carry information away from a brain region.

• Interneurons connect neurons within specific regions of the central nervous system.

Key Terms

efferent: a neuron that transmits signals from the central nervous system to the effector cells (e.g., motor neurons)

afferent: a neuron that conveys information from tissues and organs into the central nervous system (e.g., sensory neurons)

neurons: a basic working unit of the brain

CNS: central nervous system consists of the brain and spinal cord

interneurons: connect neurons within specific regions of the central nervous system