6.1 - Functions and Divisions of the Nervous System

Sensory input

The process of detecting and gathering information via specialized sensory receptors found throughout the body

Stimuli

Changes that occur within and outside of the body that are detected by sensory receptors

Integration

The nervous system's process of processing and interpreting information received from sensory input to decide if a response is needed

Motor output

The process where the nervous system produces a response through activation of an effector organ (typically a muscle or gland)

Effector organ

The target organ (typically a muscle or gland) that responds to nervous system commands

Central nervous system (CNS)

One of the two main divisions of the nervous system; consists of the brain and spinal cord; responsible for integrating, processing, and coordinating sensory data and motor commands

Peripheral nervous system (PNS)

One of the two main divisions of the nervous system; includes all nerves not in the brain or spinal cord (cranial and spinal nerves); serves as communication lines between the CNS and the rest of the body

Somatic sensory receptors

Sensory receptors that detect positioning of joints/muscles, touch, pressure, pain, and temperature

Visceral receptors

Sensory receptors that detect changes in internal organs such as blood pressure, presence of chemicals, or mechanical changes like stretch

Special receptors

Sensory receptors that detect sensations of vision, hearing, taste, smell, and balance

Afferent signals

Sensory signals sent from PNS receptors towards the CNS

Efferent signals

Motor signals sent from the CNS out to effectors via the motor division of the PNS

Somatic nervous system

The voluntary division of the PNS motor branch; innervates skeletal muscle

Autonomic nervous system (ANS)

The involuntary division of the PNS motor branch; innervates glands, smooth muscle, cardiac muscle, and adipose tissue

Sympathetic nervous system

Division of the autonomic nervous system that activates and prepares the body for vigorous muscular activity, stress, and emergencies

Parasympathetic nervous system

Division of the autonomic nervous system that operates during normal situations, permits digestion, and conserves energy

CNS function

Control centers and integration of signals

PNS function

Communication lines between the CNS and the rest of the body

CNS organs

Brain and spinal cord

PNS organs

Cranial and spinal nerves

CNS protection

Bone (skull and vertebrae) and meninges

PNS protection

Connective tissue

CNS cell body clusters

Nuclei

PNS cell body clusters

Ganglia

CNS group of axons

Tracts

PNS group of axons

Nerve

CNS damage effect

Can cause global effects on the body or affect large areas

PNS damage effect

Local effects

CNS axon regeneration

Axons do not repair

PNS axon regeneration

Axons may repair depending on the injury