Autonomic Nervous System Flashcards Preview

Functional Neuranatomy > Autonomic Nervous System > Flashcards

Flashcards in Autonomic Nervous System Deck (40):
1

chief goals of the autonomic nervous sytem

-maintain homeostasis
-allostasis
-adjustments sometimes, but rarely, require voluntary actions and awareness of internal state sometimes comes to consciousness via emotional experience

2

homeostasis

-steady state of bodily function centered around a set point

3

allostasis

-stability through change

4

multi-units

-involve large numbers of postganglionic fibers, each in close contact with smooth muscle fibers
-this arrangement provides independent and more precise control of contraction

5

single units

-involve small numbers of postgangionic fibers, which only contact a small number of muscle fibers
-the smooth muscle fibers not in direct contract either receive transmitter via diffusion or are activated via gap junctions
-the fibers contract in synchrony

6

Sympathetic effect on pupil: ciliary muscle

dilation!: increases light
-ciliary relaxation leads to far vision

7

parasympathetic effect on pupil and ciliary muscles

pupil: contracts (sphincter)---> decreases light
ciliary muscle contracts --> near vision

8

sympathetic effects on lacrimal, salivary glands

-vasoconsriction, slight secretions and decreased digestions! This allows blood to flow to muscles

9

parasympathetic effects on lacrimal, salivary glands

-vasodilation; copious- this cleans the cornea
-watery secretions- increase digestion

10

sympathetic effects on the heart

-increased heart rate, increased force of contraction, and ouput; coronary vasodilation (B)
-these all seek to enhance cardiovascular performance

11

parasympathetic effects on the heart

-decreased heart and cardiac output
-heart is at rest

12

sympathetic effects on bronchi and lungs

-bronchodilation (B), decreased secretions, and increased respirations

13

parasympathetic effect on the bronchi and lungs

-bronchoconstriction and increased secretions
-this helps remove contaminants

14

sympathetic effects on the stomach, pancreas, and intestines

decreased peristalsis, decreased secretion, and vasocconstriction

15

parasympathetic effects on the stomach, pancreas, and intestines

-increased peristalsis and secretion; vasodilation

16

sympathetic effects on urinary bladder

-constriction of internal sphincter; urinary retention

17

parasympathetic effects on the urinary bladder

-contraction of detrusor muscle; relaxation of internal sphincter

18

sympathetic effects on extremities

-sweat secretion, vasoconstriction, piloerection, vasodilation in muscles (B)
-this redistributes blood flow to the muscles and it decreases temperatures

19

sympathetic effects on the face

-vasodilation and blushing

20

mydriasis

-dilation of the pupil

21

superior cervical ganglion

-gives out sympathetic dilatory fibers

22

ciliary ganglion

-gives out parasympathetic fibers

23

pupillary light reflex is mediated by

-parasympathetic system

24

accessory oculomotor nucleus is also called the

-Edinger-Westphal

25

how will the pupillary light reflex show unilateral optic nerve damage?

-the reflex will be abolished in both eyes, but only when light is shown into the ipsilateral eye

26

how will unilateral oculomotor nerve damage affect the pupillary light reflex?

-will abolish then reflex in the ipsilateral eye, regardless of where light is shown

27

a patient with fixed and dilated eyes may be suspected of having

-damage to the midbrain

28

What drug can suppress the pupillary light reflex?

-atropine

29

what is the main pacemaker of the heart? What is its backup?

-the sinatrial node is the main pacemaker of the heart (SA node)
-the atriventricular node (AV) can operate as pacemaker if the SA node is disabled

30

sympathetic innervation to the heart comes from the

-paravertebral chain and extends beyond the nodes to the cardiac muscle itself

31

do many autonomic nerves carry sensory fibers and motor fibers?

-YES!

32

sensory cells of the autonomic nervous system

-typically pseudounipolar
-soma typically in cranial or dorsal root ganglia
-most are thin Ad or c fibers
-can be nociceptors, chemoreceptors, and mechanoreceptors

33

where do chemoreceptors of blood gases lie in the body?

-carotid body: between the internal and external branches of the carotid artery

34

chemoreceptor cells release transmitter onto afferents of which cranial nerve?

glossopharyngeal nerve

35

where does the glossopharyngeal project to after it receives transmitter from the chemoreceptors

nucleus of the solitary tracts

36

the nucleus of the solitary tracts will alter the activity of the

-reticulospinal neurons and increase respiratory rate and increase blood flow to the brain

37

where do stretch receptors lie? what do they do?

-stretch receptors detect blood pressure and lie within the carotid sinus of the carotid artery

38

the caudal nucleus of solitary tract (NTS) receives

visceral afferents signals from the vagus and glossopharyngeal nerves

39

the efferents of the NTS include

ascending inputs to other nuclei that regulate autonomic function like the hypothalamus and the limbic system

40

Horner's syndrome

associated with interruption of the sympathetic input to the head, usually as a result of a tumor to the superior cervical ganglion
-unilateral
-face is warm due to lack of sympathetic input
-drooping eyelids
-maybe caused by internal carotid dissection which could lead to massive strokes