Functions of the nervous system
The nervous system is the main control and communication centre of the body and is responsible for specific functions of communication with the different body systems. The nervous system has three main functions which include, sensation interpretation and response.
Sensation is he gathering of the different information stimuli from both the internal and external environment, this could include sight, taste and touch for example. This incoming information is then interpreted by the central nervous system where a decision is made on the most appropriate response to take. Many of these response made by the nervous system are automatic or involuntary, these occur without any conscious control, such as dilation of blood vessels or the secretion of digestive enzymes. Other responses can also be voluntary or consciously controlled such as desired muscle action to achieve a movement.
Watch this blog post here...
So how does the nervous system work in action? Well the sensory neurons of the peripheral nervous system (PNS) such as thermo, mechano & baroreceptors carry messages to the central nervous system (CNS) from the sensory organs such as the skin or eyes, to the posterior aspect of the spinal cord.
The CNS will analyse this sensory information and elicit a specific response by producing an action potential in a motor neuron traveling out of the anterior aspect of the spinal cord back to peripheral nervous system. This response will either be voluntary via the somatic peripheral nervous system, such as a conscious muscle contraction to produce movement. Or the response could be involuntary via the autonomic peripheral nervous system, such as a the innervation of smooth muscle enabling food to travel though the digestive system, the increase or decrease of the heart beat, or the secretion of hormones from various the glands.
All involuntary responses of the autonomic peripheral nervous system are regulated and maintained by the central nervous system known as homeostasis. This is achieved by the increase and decrease of the various bodily functions. When a function increases or is stimulated, this is a sympathetic response also know as fight or flight, where the bodies typically primes itself during stress to in readiness to take action (fight or flight). When a function decreases or is reduced, this is a parasympathetic response also known as rest and digest, this is where the bodies typically calms itself to de-stress starting a negative feedback loop.