Introduction to The Nervous System Physiology

What Entails The Nervous System?

The nervous system includes all neural tissue present in the body. It is the master controlling and communicating  system of the body. It accounts for just 3% of total body weight.

Its cells communicate by electrical and chemical signals, which are rapid and specific, and usually cause almost immediate responses.

Functions

The three overlapping general functions of this system are:

1. Receiving Stimuli = Sensory Function.
   It uses its millions of sensory receptors to monitor changes occurring both inside and outside the body. The gathered information is called sensory input.
2. Deciding about stimuli = integrative function
   It processes and interprets sensory input and decides what should be done at each moment—a process called integration.
3. Reacting to stimuli = motor function
   It causes a response, called motor output, by activating effector organs.

The Sensory Function

Sensors known as receptors detect changes in the internal and external environment of the body.
The function of these sensory receptors is to gather information.

Then this information gathered is transduced or changed to an electrical form by these receptors.
The information/impulses then are carried into the central nervous system using sensory nerves, or afferents.

Integrative Function

The sensory information which has been gathered by the sensory receptors is processed and channeled so that it can be :

• Used for Immediate responses/action.
• Stored for Future responses (Memory).
• Stored to be used in Thought processes.

Motor Function

The processed information is carried to effectors by motor nerves (somatic or autonomic). Once at the effector organ the information is acted upon to control various bodily activities such as muscle contraction and glandular Secretions.

Divisions of The Nervous System

This system is divided into two divisions:

1. Central Nervous System (CNS) which entails The Brain and Spinal cord.
2. Peripheral Nervous System (PNS) encompassing of :

•  
  • Somatic
  • Cranial nerves
  • Spinal nerves
  • Autonomic
  • Sympathetic
  • parasympathetic

After looking at the basic introduction we recommend that you check our article here covering the cells of the nervous system in detail.