8. Autonomic Nervous System

Autonomic Nervous System

The autonomic nervous system (ANS) is an essential part of the human nervous system that controls and regulates the body's involuntary functions. This includes, but is not limited to, heart rate, digestion, pupil dilation, urination, and even the stress response. This system is made up of two main parts: the sympathetic nervous system and the parasympathetic nervous system.

Sympathetic Nervous System

The sympathetic nervous system is responsible for preparing the body for emergency actions or stress response, often referred to as the "fight or flight" response. When activated, it increases your heart rate, dilates your pupils, slows digestion, and increases blood flow to your muscles. All of these effects help the body prepare for an emergency or stressful situation.

Parasympathetic Nervous System

On the other hand, the parasympathetic nervous system is responsible for keeping the body in a state of rest and digest. It slows your heart rate, constricts your pupils, increases digestion, and reduces blood flow to your muscles. These functions allow the body to conserve energy and recover after a stressful or emergency situation.

Interaction between Sympathetic and Parasympathetic

Although the sympathetic and parasympathetic nervous systems are functionally opposite, they work together to keep the body in a state of homeostasis. For example, during a state of stress, the sympathetic system will be activated to prepare the body for action. However, once the stressful situation has passed, the parasympathetic system will be activated to bring the body back to a state of rest and recovery.

Functions of the Autonomic Nervous System

As mentioned previously, the ANS controls a variety of involuntary bodily functions. In addition to heart rate, digestion, and stress response, the ANS also regulates blood pressure, body temperature, and breathing rate. It is also responsible for regulating fluid and electrolyte balance in the body, as well as controlling the immune response.

Regulation of the ANS

The ANS is regulated by several parts of the brain, including the hypothalamus, brain stem, and spinal cord. The hypothalamus is the main area of ​​the brain responsible for regulating the ANS. It receives information from various parts of the body and the external environment and then sends signals to activate or deactivate the sympathetic or parasympathetic system as needed.

Conclusion

In summary, the autonomic nervous system is an essential part of the human nervous system that controls and regulates the body's involuntary functions. It is made up of the sympathetic nervous system, which prepares the body for action, and the parasympathetic nervous system, which helps the body rest and recover. Through the interaction between these two systems, the body is able to maintain a state of homeostasis and respond effectively to stress and emergency situations.

Next page of the Free Ebook:

9Neurons and their functions

3 minutes