9. Human nervous system - Introduction

Thinking involves high complex mechanisms and neural connections. The neural connections formed by the peripheral nervous system, i.e., by the nerves of the spinal cord and cranial nerves, supply information to think about, i.e., these nerves receive sensory inputs or information from the different parts of the body and communicate it to the brain.

 

Neural connections are concentrated in the brain, which is the main coordination centre of the body. Thus the information received from all the parts of the body through the peripheral nervous system is integrated and processed through the central nervous system—brain and spinal cord.

 

Walking, talking, jumping into a swimming pool, opening a door, clapping at the end of each song in a musical concert are voluntary actions, which are logical decisions based on the reasoning of what to do next.

 

After integrating and processing the information received from different parts of the body, the brain will make decisions and send messages to the muscles to do actions. These actions are called voluntary actions.

 

Thus brain allows us to think and take actions based on that thinking. 

 

Mouthwatering while seeing food, heart beating, breathing through lungs, food digestion are examples of involuntary actions. We will not do these actions through the process of thinking.

 

Thus, involuntary action is the set of muscle movements controlled by the brain, which does not require any thinking control. This entire process of thinking and taking actions is accomplished through the complex design of the brain and spinal cord.