The nervous system, also known as the neural system, is a complex network of neurons that are specialised in the transmission of information. As we progress from lower animals to higher creatures, the complexity of the nervous system grows.
For example, cnidarians such as jellyfish have nerve nets that are relatively simple in design and are distributed throughout their bodies. Crabs have a more complex nervous system, which comprises two nerve centres known as the dorsal ganglion and the ventral ganglion, which are located on either side of the body.
Higher creatures, such as vertebrates, have a more evolved brain as we progress up the evolutionary ladder. Furthermore, it is one of the most complex structures in the animal kingdom, including billions of neurons that are tightly coupled to one another and to other neurons.The neural system in the human body combines the actions of organs based on the stimuli that are detected and sent by the neurons in the body. They send and receive messages in the form of electrical impulses, and they communicate with the sense organs both internally and externally. As a result, the participation of the sense organs, nerves, spinal cord, and brain is necessary for the coordination of the neurological system.
Human Nervous system
The central nervous system and the peripheral nervous system are the two divisions of the human nervous system, respectively. The central nervous system, sometimes known as the CNS, is made up of the brain and the spinal cord. The peripheral nervous system is comprised of all of the nerves that exit the body and communicate with the central nervous system.
The somatic and autonomic nervous systems are the two divisions of the peripheral nervous system.
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The Somatic Nervous System (SNS) is responsible for transmitting information from the central nervous system to the skeletal muscles. It plays a role in the voluntary control of bodily movement. Afferent (sensory) and efferent (motor) circuits are involved in this process.
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The autonomic nervous system is responsible for relaying signals from the central nervous system to involuntary organs and smooth muscles. It regulates the operation of visceral organs such as the heart muscles, smooth muscles, glandular epithelium, and other similar structures and organs. It is in charge of controlling the body’s involuntary activities. It exclusively deals with motor impulses from the central nervous system (CNS), which are used to regulate involuntary activities of visceral organs.
The autonomic nervous system is further subdivided into the sympathetic and parasympathetic nervous systems, which are both involved in digestion.
What is the Visceral Nervous System, and how does it work?
The peripheral nervous system includes the visceral nervous system, which is a part of it. It is made up of all of the nerves that transmit information between the central nervous system and the visceral organs.
Various internal organ sensory inputs travel to the central nervous system (CNS) via afferent neurons and evoke responses by efferent autonomic nerves.
The autonomic nervous system (ANS) is also referred to as the efferent visceral nervous system (motor nervous system). It regulates the body’s autonomic activities, such as heart rate, respiration, digestive secretions, sexual arousal, flight or fight responses, and reflex actions, such as coughing, vomiting, swallowing, and so on. It is found in the brain and spinal cord.
There are two major divisions in the autonomic nerve system. They are as follows:
Involvement of the Sympathetic Nervous System –
The sympathetic nervous system is involved in the “fight or flight” reaction. It often activates a large number of organs at the same time in order to elicit a rapid reaction. It causes an increase in heart rate as well as an increase in blood flow to the skeletal muscles and the lung. It has an inhibitory effect on digestion and peristalsis. It causes the pupil to dilate, allowing more light to enter the lens as a result.
Sympathetic Nervous System –
The parasympathetic nervous system is frequently associated with the rest and digest responses, both of which are gradually triggered. It aids in the return of muscles to their usual condition of rest and relaxation. In addition to increasing blood flow to the gastrointestinal tract, it also speeds up the process of peristalsis, digestion, and absorption of nutrients. It has the effect of constricting the pupil and contracting the ciliary muscle. It also has the additional effect of increasing sexual arousal.
The sympathetic and parasympathetic nerve systems have mostly opposing effects on the body, and a healthy balance between the two is necessary for equilibrium.
Conclusion
When the environment changes, living organisms adjust their movements and locations in order to protect themselves or gain an edge over the other organisms. It is referred to as stimulus when an entity reacts to changes in its environment, and it is referred to as response when the entity’s reaction to the stimulus is followed by another reaction to the stimulus. Sound, light, air, heat, smell, taste, water, and gravity are all examples of common stimuli.
Consider the sensation of burning your finger or breaking a bone without experiencing any pain. It may appear to be a superpower or a perfect circumstance on the surface, but from the aspect of survival, it can be quite detrimental.
The ability of living organisms to respond to stimuli through the intervention of the Nervous System is a typical behaviour observed in their behaviour. It is an organ system that is responsible for transmitting signals from the spinal cord and the brain throughout the body and then back to the brain from all of the body’s parts. The neuron is the basic signalling unit of the nervous system and serves as a mediator between other cells.