Autonomic Nervous System Overview

These flashcards cover key vocabulary related to the autonomic nervous system as presented in the lecture notes.

Autonomic Nervous System (ANS)

A part of the nervous system that controls involuntary bodily functions, including heart rate and digestion.

Sympathetic Division

Part of the ANS responsible for 'fight or flight' responses; mobilizes energy during stressful situations.

Parasympathetic Division

Part of the ANS that promotes 'rest and digest' functions; conserves energy and manages maintenance activities.

Efferent Pathways

Nerve pathways that carry signals away from the central nervous system to effectors.

Preganglionic Neuron

A neuron that transmits signals from the CNS to a ganglion in the autonomic nervous system.

Postganglionic Neuron

A neuron that carries signals from a ganglion to the effector organs in the autonomic nervous system.

Neurotransmitter Effects in ANS

The effects on target organs depend on the type of neurotransmitter and receptors; can be stimulatory or inhibitory.

Dual Innervation

Most internal organs receive nerve fibers from both the sympathetic and parasympathetic divisions.

Sympathetic Tone

The continuous level of sympathetic activity that helps regulate various physiological parameters.

Ach

Acetylcholine, a neurotransmitter used by both somatic and autonomic nervous systems.

Adrenergic Fibers

Nerve fibers that release norepinephrine, primarily in the sympathetic nervous system.

Cholinergic Fibers

Nerve fibers that release acetylcholine; includes all parasympathetic neurons.

Local Effects of Parasympathetic Division

The effects of the parasympathetic division are short-lived and localized due to rapid destruction of acetylcholine.

Brain Stem Control of ANS

The brain stem regulates basic autonomic functions such as heart rate, blood vessel diameter, and gastrointestinal activities.

Hypothalamus

The main integrative center for autonomic nervous system activity, controlling various bodily functions.