Autonomic Nervous System
The Autonomic Nervous System is part of the peripheral nervous system (PNS). The autonomic nervous system (ANS) is also called the vegetative nervous system. It controls the involuntary function and influences the activity of internal organs. The autonomic nervous system is regulated by the hypothalamus and is required for cardiac function, respiration, and other reflexes, including vomiting, cough, and sneezing.
Structure of the Autonomic Nervous System:
The autonomic nervous system is located at the external side of the spine in front of the spinal cord has two parallel lines of ganglia. Its fine nerve fibers are connected with each other. The nerves from this ganglion go to heart, lungs, stomach, intestine, arteries, sweat glands and iris of the eye.
Autonomic Nervous System Divisions
Division of Autonomic Nervous System:
The autonomic nervous system can be divided into:
- Sympathetic nervous system
- Parasympathetic nervous system
The Sympathetic Nervous System (SNS):
The sympathetic nervous system (SNS) is an arousing system. It increases the heartbeat and blood pressure. It supplies blood to the muscles of legs and arms. It is active in the emotion of anger and fear. It arouses for defense making one alert and ready for action by accelerating the heartbeat, slowing the digestion, raising the blood sugar and blood pressure, dilating the arteries and perspiration.
The Parasympathetic Nervous System (PSNS):
The parasympathetic nervous system (PSN) produces the opposite effects. It calms down the person by decreasing the heartbeat, lowering his blood pressure and blood sugar. Thus it helps in storing the energy, activating the digestive and excretory system.
The sympathetic and parasympathetic nervous system work together. They shower the body patterns of expressions in emotions and keep us in a steady normal state.
Anatomy of the Autonomic Nervous System
Autonomic Nervous System Function
Functions of the Autonomic Nervous System are described below by the following responses:
The sympathetic division of the autonomic nervous system maintains internal organs homeostasis and initiates the stress response. The sympathetic nervous system is responsible for regulating many homeostatic mechanisms in living organisms. Fibers from the SNS innervate tissues in almost every organ system and provide physiological regulation over diverse body process including pupil diameter, gut motility (movement), and urinary output
The SNS is perhaps best known for mediating the neuronal and hormonal stress response commonly known as the fight-or-flight response, also known as the Sympathoadrenal response of the body. This occurs as the preganglionic sympathetic fibers that end in the adrenal medulla secrete acetylcholine, which activates the secretion of adrenaline (epinephrine) and to a lesser extent noradrenaline (norepinephrine).
The parasympathetic nervous system (PSNS, or occasionally PNS) is one of the two main divisions of the autonomic nervous system (ANS). The autonomic nervous system is the peripheral nervous system that acts as a control system, functioning largely below the level of consciousness and controlling visceral function. It regulates organ and gland functions during rest and is considered a slowly activated, dampening system.
A useful acronym to summarize the function of the parasympathetic nervous system is SLUDD (salivation, lacrimation, urination, digestion, and defecation).
Autonomic Nervous System Dysfunction
Autonomic dysfunction develops when the nerves of the ANS are damaged. This condition is called Autonomic Neuropathy or Dysautonomia. Autonomic dysfunction can range from mild to life-threatening. It can affect the part of ANS or the entire ANS.
Sometimes the conditions that cause problems are temporary and reversible. Others are chronic or long term and may continue to worsen over time. Autonomic Nervous System pdf also provides brief information about this.
Diabetes and Parkinson’s disease are two examples of chronic conditions that can lead to autonomic dysfunction.
Autonomic Nervous System Dysfunction Symptoms:
Autonomic dysfunction can affect a small part of the ANS or the entire ANS. Some symptoms that may indicate the presence of an autonomic nerve disorder include:
- Dizziness and fainting upon standing up, or orthostatic hypotension.
- An inability to alter heart rate with exercise, or exercise intolerance.
- Sweating abnormalities
- Urinary problems
- Vision problems
Autonomic Nervous System Dysfunction Types:
Different types of Autonomic Dysfunction include:
- Postural Orthostatic Tachycardia Syndrome (POTS):
POTS affects anywhere from 1 to 3 million people in the United States. It can affect children, teenagers, and adults. POTS symptoms can range from mild to severe. Up to one out of four people with POTS have significant limitations inactivity and are unable to work due to their condition.
- Neurocardiogenic Syncope (NCS):
NCS is also known as vasovagal syncope. It is a common cause of syncope or fainting. The fainting is s result of a sudden slowing of blood flow to the brain and can be triggered by dehydration.
- Multiple System Atrophy (MSA):
MSA is a fatal form of autonomic dysfunction. Early on, it has symptoms similar to Parkinson’s disease. But people with this condition usually have a life expectancy of only about 5 to 10 years from their diagnosis. The cause of MSA is unknown, and no cure or treatment slows the disease.
- Hereditary Sensory and Autonomic Neuropathic (HSAN):
HSAN is a group of related genetic disorders that cause widespread nerve dysfunction in children and adults. The inherited patterns, and symptoms.
- Holmes-Adie Syndrome (HAS):
HAS mostly affected the nerves controlling the muscles of the eye, causing vision problems. One pupil will likely be larger than the other, and it will constrict slowly in bright light. Eye drops and glasses can help correct vision difficulties.
- Other types of Autonomic Nervous System Dysfunction :
Other types of autonomic dysfunction can result from disease or damage to your body. Autonomic neuropathy refers to damage to nerves from certain medications, injury, or disease. Some diseases causing this neuropathy include:
- Uncontrolled high blood pressure
- Long-term heavy drinking
- Autoimmune disorder
Treatments of Autonomic Autonomic Nervous System Dysfunction :
Your doctor will treat Autonomic Dysfunction by addressing the symptoms. Often, orthostatic hypotension can be helped by lifestyle changes and prescription medication. The symptoms of orthostatic hypotension may respond to:
- Elevating the head of your bed
- Drinking enough fluids
- Adding salt to your diet
- Wearing compression stockings to prevent blood pooling in your legs
- Changing positions slowly
- Taking medications like Midodrine
Nerve damage is difficult to cure. Physical therapy, walking aids, feeding tubes, and other methods may be necessary to help treat more severe involvement.
Autonomic Nervous System Quizlet
Examples of the Autonomic Nervous System Response
Fight or Flight Responses
The fight-or-flight response was first described by Walter Bradford Cannon. His theory states that animal reacts to threats with a general discharge of the sympathetic nervous system, priming the animal for fighting or fleeing. This response was later recognized as the first stage of a general adaptation syndrome that regulates stress responses among vertebrates and other organisms.
The sympathetic and parasympathetic autonomic nervous systems cooperatively modulate internal physiology to maintain homeostasis. Sympathetic and parasympathetic divisions typically function in opposition to each other. However, this opposition is better termed complementary in nature rather than antagonistic. For an analogy, one may think of the sympathetic division as the acceleration and the parasympathetic division as the brake.
Hormones and the Autonomic Nervous System
Autonomic Nervous System and the Cardiovascular System
Autonomic Nervous System Disorders
There is a large kind of autonomic systema nervosum disorders among humans. Over one million Americans each year can expertise dysfunction of the involuntary system, called dysautonomia. Since the ANS is especially liable for the fight-or-flight response and therefore the breed-and-feed response, any disorder can possibly have an effect on one in all these two systems.
For example, a typical ANS disorder is male erecticle dysfunction or the shortcoming for a male to induce an erection. different dysautonomias include digestive malfunction, heart or respiratory organ management problems, and different malfunctions involving systems that are generally underneath the management of the subconscious. as a result of the ANS controls numerous aspects of the body, dysautonomias include an enormous variety of disorders.