ANS, Hypothalamus and Limbic System

Question 1

Autonomic Nervous System

Answer 1

Influenced by hypothalamus

Question 2

ANS Functions

Answer 2

Maintains homeostasis

Regulates activity of internal organs and vasculature

Question 3

Mechanoreceptors

Answer 3

Respond to pressure and stretch

Question 4

Chemoreceptors

Answer 4

Sensitive to chemical concentrations in blood, medulla and hypothalamus
Stomach, taste bud and olfactory bulbs are examples

Question 5

Nociceptors

Answer 5

Respond to stretch and ischemia

Question 6

Thermoreceptors

Answer 6

Respond to small changes in temperature of circulating blood

Question 7

Information from visceral receptors into CNS via….

Answer 7

Spinal cord via dorsal roots

Brainstem via CN VII, IX and X

Question 8

Central Regulation

Answer 8

Visceral information enters brainstem and converges in solitary nucleus
From solitary nucleus, relayed to control areas in pons and medulla
Relayed to modulatory areas in hypothalamus, thalamus and limbic system

Question 9

Location of Solitary Nucleus

Answer 9

Medulla

Question 10

Central Regulation (Medulla)

Answer 10

Regulates heart rate, respiration, vasoconstriction and vasodilation

Question 11

Central Regulation (Pons)

Answer 11

Regulates respiration

Question 12

Central Regulation (Hypothalmus, Thalamus, and Limbic System)

Answer 12

Modulate brainstem autonomic control
Influences cardiorespiratory, metabolic, water reabsorption and digestive activity by acting on pituitary and control centers
Information is projected to limbic system

Question 13

Who sends information directly to hypothalamus?

Answer 13

Olfactory

Small part of visual

Question 14

Limbic System Components

Answer 14

Hypothalmus
Nuclei of Thalamus
Limbic cortex
Hippocampus - memory center
Amygdala - fear

Question 15

Limbic System Functions

Answer 15

Emotion and memory functions

Influences motor and autonomic output via emotion

Question 16

Sympathetic System

Answer 16

“Fight or Flight”

Cell bodies of preganglionic located in lateral horn (T1-L2)

Question 17

Sympathetic System Function

Answer 17

Maintain optimal blood supply to organs
Regulate body temperature and metabolic rate
Regulates activity of viscera

Question 18

Parasympathetic System

Answer 18

“Rest and Digest”

Preganglionic cell bodies in brainstem and sacral spinal cord (S2-S4)

Question 19

Parasympathetic System Function

Answer 19

Energy conservation and storage
Decreases cardiac activity
Facilitates digestion
Regulates activity of viscera

Question 20

Sympathetic Characteristics

Answer 20

Lot of input coming in
Two neuron system
Ganglia located closer to spinal cord
One neuron connection with adrenal gland

Question 21

Parasympathetic Characteristics

Answer 21

Not a lot of input coming in, but vagus is important

Two neuron system

Question 22

Neurotransmitters Released by ANS

Answer 22

Acetylcholine

Norepinephrine

Question 23

Peripheral Nerve Injury (Clinical Correlation)

Answer 23

Loss of vascular control
Temperature regulation
Sweating

Question 24

Spinal Region Injury (Clinical Correlation)

Answer 24

Completer S2-4 lesion or cauda equina produces flaccid bladder
Above sacral cord, hypertonic/hyperreflexive bladder
Lesion above T6 - autonomic dysreflexia

Question 25

Brainstem Injury (Clinical Correlation)

Answer 25

Interfere with descending control of HR, BP and respiration

Affects cranial nerve nuclei

Question 26

Cerebral Injury (Clinical Correlation)

Answer 26

Disrupts homeostasis with metabolic and behavioral dysfunctions