Autonomic Nervous System

Physiology

• ANS is a division of the peripheral nervous system that supplies internal organs, smooth muscle and glands.
• It is a control system that acts largely unconsciously and regulates bodily functions, such as
  • Heart rate and its force of contraction
  • Digestion
  • Respiratory rate
  • Pupillary response
  • Urination
  • Sexual arousal
  • Fight-or-flight response
  • Vasomotor activity (the vasomotor center)
  • Certain reflex actions such as coughing, sneezing, swallowing and vomiting.

• ANS is regulated by integrated reflexes through the brain-stem to the spinal cord and organs.
• Hypothalamus acts as an integrator for autonomic functions, receiving autonomic regulatory input from the limbic system.

ANS branches

ANS has four branches:

1. Sympathetic nervous system
2. Parasympathetic nervous system
3. Visceral / Sensory nervous system
4. Enteric nervous system

Sympathetic division

• It consists of cells with bodies in the lateral grey column from T1 to L2/3.
• These cell bodies are "GVE" (general visceral efferent) neurons and are the preganglionic neurons.s

• These all contain afferent (sensory) nerves as well, known as GVA (general visceral afferent) neurons.

Parasympathetic division

• It consists of cells with bodies in one of two locations:
  1. Brainstem (Cranial Nerves III, VII, IX, X)
  2. Sacral spinal cord (S2, S3, S4). These are the preganglionic neurons, which synapse with postganglionic neurons in these locations:

• These ganglia provide the postganglionic neurons from which innervations of target organs follows. Examples are:
  • Postganglionic parasympathetic splanchnic (visceral) nerves
  • Vagus nerve which innervates heart, lungs, liver and stomach

Sensory neurons

• It is composed of primary visceral sensory neurons found in the peripheral nervous system (PNS) in cranial sensory ganglia
• These sensory neurons monitor the
  • Levels of carbon dioxide, oxygen and sugar in the blood
  • Arterial pressure
  • Chemical composition of the stomach and gut content.
  • They also convey the sense of taste and smell, which, unlike most functions of the ANS, is a conscious perception.
  • The nTS also receives input from a nearby chemosensory center, the area postrema, that detects toxins in the blood and the cerebrospinal fluid and is essential for chemically induced vomiting or conditional taste aversion (the memory that ensures that an animal that has been poisoned by a food never touches it again).
  • All this visceral sensory information constantly and unconsciously modulates the activity of the motor neurons of the ANS.
  • Pain in any internal organ is perceived as referred pain, more specifically as pain from the dermatome corresponding to the spinal segment.

Target organ/system	Parasympathetic	Sympathetic
Digestive system	Increase peristalsis Increase secretion of digestive glands	Decrease activity of digestive system
Liver	No effect	Releasing glucose to blood
Lungs	Constricts bronchioles	Dilates bronchioles
Urinary bladder/ Urethra	Relaxes sphincter	Constricts sphincter
Kidneys	No effects	Decrease urine output
Heart	Decreases rate	Increase rate
Blood vessels	No effect	Constricts blood vessels in viscera; increase BP
Salivary and Lacrimal glands	Increases saliva and tears	Dry mouth /eyes
Eye (iris)	Constrict pupils	Dilates pupils
Eye (ciliary muscles)	Increase bulging of lens for close vision	Decrease bulging of lens; prepares for distant vision
Adrenal Medulla	No effect	Increase secretion epinephrine / norepinephrine
Sweat gland of skin	No effect	Increase perspiration
Sexual organs	Erection of genital tissues Stimulating sexual arousal.

Dysautonomia entities

• Syncope

• Dysautonomia is an umbrella which contains different entities depending on which part of ANS is affected

Clinical Types

• Afferent Baroreflex Failure
• Familial Dysautonomia

• Hereditary sensory and autonomic neuropathies (HSAN)

• Holmes-Adie syndrome (HAS)
• Autonomic neuropathy

Related diseases

Disease	Pathology	Entities	Miasms
POTS (Postural orthostatic tachycardia syndrome)	General Sympathetic Hyperactivity	Hypotention (Orthostatic) Tachicardia Disorientation	RBS
Vasovagal Syncope	General Parasympathetic Hyperactivity	Hypotention Coma Dizziness	SAHF
IBS-C	Local Symp/ Parasympathetic Dysregulations	Ileus Constipation	EBV
IBS-D	Local Symp / Parasympathetic Dysregulations	Ileus Gastroenteritis / Diarrhea	CMV
IBS-M	Local Symp / Parasympathetic Dysregulations	Ileus Constipation	EBV
Gasteroparesis / GERD	Local symp / Parasympathetic Dysregulations	Gastric Dilation	PLV
GAD		Anxiety Anhydrosis
Pure Autonomic Failure = Neurogenic syncope Neurocardiogenic syncope (NCS)

My research

I determine Syncope as an entity for Authonomic dysfunction

	General Sympathetic Hyperactivity	General Parasympathetic Hyperactivity	Local symp / Parasympathetic dysregulations
	Anxiety	Depression	Constipation
	Anhydrosis	Dizziness / Brain fog	Dysphagia
	Insomnia	Exercise intolerance / Weakness	Bowel incontinence
	Tachycardia	Syncope/ Orthostatic hypotension	Urinary incontinence or
	Tunnel vision	Vertigo	Urinary retention
		Blurry or double vision
Miasms	RBS	HSV-1, CMV

3 Related disease

Dysautonomia has many causes, not all of which may be classified as neuropathic such as

• Autonomic neuropathy
• HIV/AIDS
• Postural orthostatic tachycardia syndrome (POTS)
• Alcoholism
• Amyloidosis
• Autoimmune disease such as
  • Sjögren's syndrome
  • SLE
  • Autoimmune autonomic ganglionopathy
• Craniocervical instability
• Diabetes
• Eaton-Lambert syndrome
• Ehlers-Danlos syndrome
• Guillain-Barré syndrome
• Long COVID
• Multiple sclerosis
• Paraneoplastic syndrome
• Spinal cord injury or traumatic brain injury
• Synucleinopathy, a group of neurodegenerative diseases including dementia with Lewy bodies, multiple system atrophy, and Parkinson's disease
• Surgery or injury involving the nerves
• Toxicity (vincristine)
• Parkinson’s disease
• Fibromyalgia
• Chronic fatigue syndrome
• Irritable bowel syndrome
• Interstitial cystitis
• Multiple system atrophy (MSA)

4 Causes

• Inherited or degenerative neurologic diseases (primary dysautonomia)
• Injury of the autonomic nervous system from an acquired disorder (secondary dysautonomia).

5 Anxiety vs autonomic dysfunction

Anxiety can sometimes physically manifest symptoms resembling autonomic dysfunction. A thorough investigation ruling out physiological causes is crucial, but in cases where relevant tests are performed and no causes are found or symptoms do not match any known disorders, a primary anxiety disorder is possible, but should not be presumed. For such patients, the anxiety sensitivity index may have better predictivity for anxiety disorders, while the Beck anxiety inventory may misleadingly suggest anxiety for patients with dysautonomia.

Entity / Miasm Anxiety

Syncope

Impotence

Incontinence

Gastroparesis

GERD

Achalasia

Thermoregulatory disorder

Dysauthonomia entitie