Autonomic Nervous System Overview

These flashcards cover key concepts and details related to the Autonomic Nervous System and its functions, receptors, divisions, and neuropharmacology.

What does ANS stand for?

Autonomic Nervous System.

What are the main functions of the Autonomic Nervous System (ANS)?

The ANS maintains homeostasis, regulating heart rate, respiratory rate, body temperature, blood pressure, and digestion.

What is biofeedback in the context of the ANS?

Biofeedback is the conscious control over normally unconscious processes.

How many neurons are involved in the autonomic pathways from the CNS to the effector organs?

Two neurons: a preganglionic neuron and a postganglionic neuron.

What type of muscle does the ANS control?

Cardiac muscle, smooth muscle, and glands.

What does the sympathetic division prepare the body for?

Physical activity, often referred to as 'fight or flight' response.

What effects does the parasympathetic division have on body functions?

It calms many body functions and is responsible for 'rest and digest' activities.

What are adrenergic receptors typically associated with?

They are receptors that bind norepinephrine (NE) and typically mediate excitatory effects.

What is the function of cholinergic fibers?

Cholinergic fibers secrete acetylcholine (ACh).

What is dual innervation in the context of the ANS?

Most viscera receive nerve fibers from both sympathetic and parasympathetic divisions, often having opposing effects.

What is autonomic tone?

The normal rate of activity that represents the balance of sympathetic and parasympathetic systems.

What is the role of baroreceptors in the ANS?

Baroreceptors detect blood pressure changes and send signals to regulate heart rate accordingly.

How does the sympathetic nervous system affect blood vessels?

It keeps most blood vessels partially constricted to maintain blood pressure.

What is the role of the adrenal medulla in the ANS?

The adrenal medulla releases catecholamines like epinephrine and norepinephrine into the bloodstream during stress responses.

What is the significance of neuronal convergence in the sympathetic nervous system?

Each postganglionic cell may receive signals from multiple preganglionic cells, leading to widespread effects.

What neurotransmitter is released by adrenergic fibers?

Norepinephrine (NE).

Which cranial nerves are involved in the parasympathetic division?

Cranial nerves III (oculomotor), VII (facial), IX (glossopharyngeal), and X (vagus).

What is the enteric nervous system?

It is the nervous system of the digestive system, containing about 100 million neurons and regulating digestive processes independently.

What effect does ephedrine have on sympathetic activity?

It enhances sympathetic activity by stimulating receptors or promoting norepinephrine release.

What is the function of SSRI medications in treating depression?

They increase the levels of serotonin, a mood-elevating neurotransmitter, by inhibiting its reabsorption.