Autonomic Nervous System Overview

A set of 100 vocabulary flashcards covering key concepts of the Autonomic Nervous System presented in the lecture notes.

Autonomic Nervous System

A motor division of the peripheral nervous system that controls involuntary actions.

Visceral Motor Division

Another name for the autonomic nervous system, emphasizing its control over visceral organs.

Involuntary Actions

Actions that occur without conscious control, mediated by the autonomic nervous system.

Viscera

The internal organs, particularly those within the thoracic and abdominal cavities.

Denervation Hypersensitivity

Exaggerated responses of cardiac and smooth muscle following the severing of autonomic nerves.

Autonomic Output Pathways

Pathways that involve components from both the central and peripheral nervous systems controlling autonomic functions.

Sympathetic Division

Part of the autonomic nervous system that prepares the body for physical activity.

Parasympathetic Division

Part of the autonomic nervous system that calms many body functions and reduces energy expenditure.

Autonomic Tone

The normal background rate of autonomic activity, reflecting a balance of sympathetic and parasympathetic activity.

Visceral Reflexes

Responses to stimulation involving visceral receptors that are unconscious and automatic.

Acetylcholine (ACh)

A neurotransmitter released by preganglionic fibers in both the sympathetic and parasympathetic divisions.

Norepinephrine (NE)

A neurotransmitter released by postganglionic fibers of the sympathetic division.

Autonomic Ganglion

A cluster of nerve cell bodies where preganglionic neurons synapse with postganglionic neurons.

Dual Innervation

The condition where most viscera receive nerve fibers from both parasympathetic and sympathetic divisions.

Antagonistic Effect

When the two divisions of the autonomic nervous system oppose each other's actions.

Cooperative Effects

When the sympathetic and parasympathetic divisions work together to produce a unified overall effect.

Sympathetic Vasomotor Tone

Baseline firing frequency of sympathetic nerves that keeps blood vessels partially constricted.

Central Nervous System Control

The regulation of the autonomic nervous system at multiple levels of the CNS including the hypothalamus and brainstem.

Hypothalamus

The major visceral motor control center in the brain that regulates basic functions like hunger and thirst.

Brainstem Functions

Includes nuclei for cardiovascular control, salivation, and other autonomic functions.

Spinal Cord Reflexes

Autonomic control of processes like defecation and urination, modulated by spinal reflexes.

Effectors of ANS

Organs or tissues that respond to autonomic nerve signals, such as smooth muscles and glands.

Cardiac Muscle

Muscle that is involuntarily controlled by the autonomic nervous system.

Smooth Muscle

Muscle that is also involuntarily controlled by the autonomic nervous system, found in internal organs.

Stimulatory Effect

An increase in activity or function, which can be caused by neurotransmitters in the autonomic nervous system.

Inhibitory Effect

A decrease in activity or function, which may occur depending on neurotransmitter and receptor interactions.

Preganglionic Neuron

The neuron that extends from the CNS to the autonomic ganglion.

Postganglionic Neuron

The neuron that extends from the autonomic ganglion to the effector organ.

Skeletal Muscle

Muscle that is under voluntary control and functions separately from the autonomic nervous system.

Piloerector Muscles

Muscles that cause hair follicles to stand on end, controlled by the autonomic nervous system.

Sweat Glands

Glands controlled by the autonomic nervous system that assist with thermoregulation.

Sympathetic Effects

Physiological responses that prepare the body for stressful or energetic activities.

Parasympathetic Effects

Physiological responses that promote rest and energy conservation in the body.

Integration Centers

Areas within the CNS that integrate sensory information and coordinate autonomic responses.

Cerebral Cortex

The brain region involved in higher functions that can influence the activity of the autonomic nervous system.

Limbic System

A network in the brain associated with emotions and memory that influences autonomic responses.

Emergency Responses

Rapid physiological changes mediated by the sympathetic division during stress or danger.

Effector Organs

The organs that receive signals from the autonomic nervous system leading to a physiological response.

Blood Vessels

Vessels that transport blood and are influenced by sympathetic control to adjust flow based on activity.

Hypothalamic Nuclei

Specific clusters of neurons in the hypothalamus responsible for regulating autonomic functions.

Homeostasis

The physiological state of equilibrium that the autonomic nervous system helps maintain.

Emergency Autonomic Control

Sympathetic nervous system responses that help the body cope with immediate stressors.

Neurotransmitter Varieties

Different types of chemicals released by neurons that influence target cell activity.

Neurotransmitter Receptors

Proteins on target cells that bind to neurotransmitters, determining the effect on the cell.

Adrenal Medulla

An inner portion of the adrenal gland that releases hormones influencing sympathetic responses.

Vasodilation

The widening of blood vessels that increases blood flow to an area, often affected by the ANS.

Vasoconstriction

The narrowing of blood vessels that decreases blood flow, influenced by sympathetic activity.

Synapse

The junction between two neurons where signaling occurs via neurotransmitters.

Blood Glucose Increase

An effect of sympathetic activation that provides more energy for muscles during stress.

Defense Mechanism

Physiological responses triggered by the autonomic nervous system to protect the body.

Energy Expenditure

The amount of energy used by the body, influenced by the autonomic nervous system's activity.

Smooth Muscle Control

Regulation of involuntary muscle movement by the autonomic nervous system.

Motor Neurons

Neurons that transmit signals from the central nervous system to effect muscle or gland activity.

Autonomic Reflex Arc

A neural pathway that controls involuntary responses via the autonomic nervous system.

Target Organ

The specific organ or tissue that a nerve signal is directed to in the body.

ACh Effects

The result of acetylcholine action on target tissues, which can vary based on receptor type.

NE Effects

Norepinephrine's influence on target tissues, often enhancing sympathetic responses.

Cardiovascular Control

The regulation of heart rate and blood pressure by autonomic pathways.

Urinary Control

Regulation of bladder function by the autonomic nervous system.

Emotional Response

The association between strong feelings and autonomic changes in the body.

Motor Control Regions

Specific parts of the brain that guide motor functions, including autonomic actions.

Sympathetic Growth Responses

Changes in the body that promote growth and energy use during stressful conditions.

Parasympathetic Maintenance Control

Involvement of the parasympathetic nervous system in keeping metabolic processes running smoothly.

Glandular Secretion Modulation

Regulation of hormone and enzyme release influenced by autonomic nervous system activity.

Emergency Blood Flow Redistribution

The shifting of blood supply during a crisis, prioritizing vital organs and muscles.

Innervation Variation

Differences in nerve supply distribution among organs by the autonomous nervous system.

Neurotransmitter Secretion

The release of chemical messengers by neurons to transmit signals across synapses.

Visceral Sensory Information

Sensory signals arising from internal organs that inform the autonomic nervous system.

Homeostatic Mechanisms

Processes regulated by the autonomic nervous system to maintain stable internal conditions.