differences between the Central Nervous System (CNS) and the Peripheral Nervous
System (PNS):
Aspect
Location
Components
Function
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
Located within the brain and spinal
Located outside the brain and spinal
cord.
cord, extending throughout the body.
Consists of the brain and spinal cord.
the CNS, including nerves and ganglia.
Integrates and processes sensory
Serves as a communication network
information, initiates motor commands,
between the CNS and the rest of the
and coordinates complex activities.
body.
Contains interneurons (association
Neuron Types
Comprises all nervous tissue outside
neurons) responsible for information
processing and motor neurons.
Contains sensory neurons, motor
neurons, and autonomic neurons.
Protected by the skull and vertebral
Protection
column, as well as the meninges
(protective membranes) and
cerebrospinal fluid (CSF).
Not as heavily protected as the CNS.
Blood-Brain Barrier
(BBB)
The BBB restricts the passage of certain
Lacks the BBB, allowing for easier
substances from the bloodstream into
exchange of substances between
the brain to protect neural tissue.
nerves and blood.
Contains both white and gray matter,
White and Gray
with white matter consisting of
Matter
myelinated axons and gray matter
containing cell bodies and dendrites.
Voluntary and
Responsible for both voluntary and
Involuntary Control
involuntary (reflex) actions.
Cranial Nerves and
Spinal Nerves
Motor and Sensory
Functions
Integration of
Information
The CNS communicates with the body
through 12 pairs of cranial nerves and
31 pairs of spinal nerves.
Initiates motor commands and receives
sensory input from the body and
external environment.
Predominantly consists of nerves with
myelinated and unmyelinated axons,
but less gray matter.
Primarily involved in voluntary actions.
Some autonomic reflexes involve the
PNS.
These nerves carry sensory and motor
signals between the body and the CNS.
Transmits sensory information from
sensory receptors to the CNS and
carries motor commands from the CNS
to muscles and glands.
Integrates and interprets sensory
information, forming perceptions and
Acts as a conduit for sensory
generating appropriate responses.
information to reach the CNS and for
motor commands to reach target
tissues.