Term: Peripheral Nervous System

Definition: Like the CNS, the PNS can be divided roughly into "gray matter" regions containing neuronal cell bodies and neuropil (ganglia), and "white matter" containing bundles of nerve fibers (nerves). For clarity, peripheral nerve fibers transmitting information toward the CNS are referred to as afferent, whereas those transmitting information away from the CNS are referred to as efferent. In the CNS, cell groups (regions) and fiber tracts transmitting information predominantly toward the cognitive system (cerebral hemisphere) rather than the motor system are referred to as sensory.

Nomenclature: Swanson-2004