Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NURS 6413 Advanced Physiology and Pathophysiology > Neuro PPT 2 > Flashcards

Neuro PPT 2 Flashcards

1
Q

What serves as the integrative area for cord reflexes?

A

Cord Grey matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where do sensory signals enter the spinal cord?

A

Sensory roots (Posterior or dorsal roots)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Sensory signals have Two destinations in the spinal cord. What are they?

A

Local segmental reflexes - this branch terminates in the gray matter for local reflexes

Higher system transmission: this branch sends signals to higher nervous system levels (brain stem, cortex)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are anterior motor neurons?

A

Large neurons located in the anterior horns and directly innervate muscles. Transmit impulses quickly.

Three types:
alpha motor neurons
Gamma motor neurons
Renshaw cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are interneurons

A

Found in the gray matter, highly excitable and integral to reflex arcs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Alpha motor neurons give rise to ________ motor nerve fibers

A

A alpha

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do alpha motor neurons do?

A

Stimulates multiple skeletal muscle fibers (ie: motor unit)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What do gamma motor neurons innervate?

A

Intrafusal fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Gamma motor neurons are _______ fibers

A

Small

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Gamma motor neurons give rise to ______ motor nerve fibers

A

A gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Stimulation of the intrafusal fibers by gamma motor neurons helps control _______ ________ _______

A

Basic muscle tone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are interneurons located?

A

Widely distributed throughout the cord gray matter
ie: dorsal horns, intermediate areas, anterior horns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Function of interneurons

A

Process and relay signals

Extensive Interconnections responsible for spinal integrative functions: diverging, converging, repetitive-discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Location of renshaw cells

A

Anterior horn of the gray matter

Closely associated with anterior motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Function of renshaw cells

A

Refines motor control by transmitting INHIBITORY signals from the anterior motor neuron to adjacent motor neurons

Causes lateral inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Function of propriospinal fibers

A

Form communications between spinal cord segments to coordinate multi-segmental reflexes, allowing coordination of movement between extremities.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Two types of muscle sensory receptors

A

Muscle spindles and golgi tendon organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Function of muscle sensory receptors

A

Provide continuous feedback of sensory information about muscle length and tendon tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Muscle spindles

State location and function

A

Location: muscle belly

Function: senses muscle length and rate of change of length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Golgi Tendon Organs

State location and function

A

Location: tendons

Function: senses tendon tension and rate of change of tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Feedback from the muscle sensory receptors is sent to which 3 areas?

A

Spinal cord
Brain stem
Motor areas of cerebral cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Muscle spindles consist of …

A

3-12 intrafusal fibers that taper at the ends to connect to larger extrafusal muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

T/F: Continuous transmission of nerve signals is
required for function of the cerebral cortex

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How much time does direct stimulation effects persist for?

A

Milliseconds or seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How much time does neurohormonal systems effects persist for?

A

Minutes or hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Location for the reticular excitatory area:

A

Pons/mesencephalon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Where are facilitatory signals transmitted to?

A

Spinal cord and cerebral cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Location of the reticular inhibitory areas:

A

Medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

_________ releasing nerve fibers from locus ceruleus transmit signals
throughout brain

Primarily excitatory effects, possibly involved in dreaming

A

Norepinephrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

____________ nerve fibers from raphe nuclei (i.e., medulla and pons) transmit
signals to spinal cord, diencephalon, and cerebral cortex

At spinal cord level, it is involved in pain suppression

At diencephalon and cerebral cortex level, it has inhibitory effects,
possibly involved in regulation of sleep

A

Serotonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

_________ nerve fibers from substantia nigra transmit signals to caudate
nucleus, putamen, hypothalamus, and limbic system

Primarily inhibitory effects, possibly some excitatory effects

A

Dopamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

__________ nerve fibers from gigantocellular neurons of reticular excitatory area
transmit signals to spinal cord and higher brain levels

Primarily excitatory effects, possibly involved in wakefulness

A

Acetylcholine (Cholinergic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What system:
Controls emotional behavior and motivational drive

Reward/Punishment (i.e., pleasant/unpleasant)

Vegetative functions (e.g., control of body temperature,
control of osmolality of body fluids, hunger, thirst)

A

Limbic System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Anatomy of the Limbic System:

A

SUBCORTICAL STRUCTURES

Hypothalamus- central physiologic function

Septum area, paraolfactory area, anterior nucleus of
thalamus, portions of basal ganglia, hippocampus,
amygdala

LIMBIC CORTEX

Orbitofrontal cortex, subcallosal gyrus,
cingulate gyrus, parahippocampal gyrus

Medial forebrain bundle extends from orbitofrontal
cortex through hypothalamus to brain stem reticular
formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Two-way communication exists between hypothalamus and all levels of limbic system:

A
  1. Transmits signals to brain stem then to
    peripheral nerves of ANS
  2. Transmits signals to anterior thalamus and other
    structures of limbic system
  3. Transmits signals to hypothalamic infundibulum to
    control secretion from pituitary gland
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the seven functions of the hypothalamus?

A
  1. cardiovascular regulation
  2. body temperature regulation
  3. body water regulation 4. regulation of uterine contraction and milk
    ejection
  4. gastrointestinal regulation
  5. circadian rhythm
  6. pituitary
    gland regulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Sensory experiences cause activation of
___________, which sends signals to
anterior thalamus, hypothalamus, and other
structures of limbic system

A

Hippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are the two functions of the hippocampus?

A
  1. Formation of memories
  2. Consolidation of memories
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Anatomy of the amygdala:

A

Group of nuclei situated inferiorly to medial
anterior pole of temporal lobe

Two-way communication with cerebral
cortex, hippocampus, septum, thalamus,
and, in particular, the hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are the functions of the amygdala?

A

(Stimulation causes same effects as direct stimulation of the hypothalamus

  1. tonic and clonic movements
  2. circling
    movements
  3. movements associated
    with olfaction and eating (licking,
    chewing, swallowing)
  4. Reward/Punishment patterns
  5. Activities of reproductive organs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Portion of cerebral cortex that
belongs to limbic system, functioning as
transitional zone and functions as the association area for behavioral
control

A

Limbic Cortex

41
Q

Unconsciousness from which a person
can be aroused by sensory or other stimuli

A

Sleep

42
Q

25% of sleep,
period of high brain activity during which
dreams occurs

How long does it occur and last?

A

REM (Rapid Eye Movement)

Occurs every 90 minutes, lasts 5-30 minutes

42
Q

Restful sleep that often occurs during the early stages of sleep:

When does it occur?

A

NREM (Non-REM)

Occurs during first hour of sleep

43
Q

Unconsciousness from which a
person cannot be aroused

A

Coma

44
Q

What are six things that occur during REM sleep:

A

1.Dreams likely to occur

2.Difficulty arousing

3.Depressed muscle tone and irregular
muscle movements

4.Irregular heart rate and respiratory rate

5.Increased brain metabolism (i.e., 20%)

6.EEG demonstrates patterns similar to
wakefulness (i.e., paradoxical sleep)

45
Q

What are three things that occur during NREM Sleep

A

1.Dreams may occur

2.Decreased BP, RR, and basal metabolic rate

3.EEG demonstrates slow, high-amplitude
waves

46
Q

Theories of Sleep Mechanisms: Early Theory vs. Current Theory

A

Early Theory: Sleep is the result of
inactivation of the reticular activating
system due to progressive fatigue throughout
the day

vs.

Current Theory: Sleep is the result of active
inhibition of higher brain areas by an area
caudal to the mid-pons

47
Q

What are the three transmitter substances of sleep?

A
  1. Serotonin: Secreted by nerve endings of fibers from the raphe
    nuclei, blockade of serotonin production leads to prolonged
    wakefulness
  2. Muramyl peptide: Low-molecular-weight peptide that
    accumulates in CSF during prolonged periods of wakefulness
  3. Delta sleep-inducing peptide: Nonapeptide present in CSF after
    electrical stimulation of thalamus
48
Q

Spontaneous activity of
reticular activating nuclei excites cerebral
cortex and peripheral nervous system, which
send excitatory signals to reticular activating
nuclei in a positive feedback loop

A

Wakefulness

49
Q

(Sleep-Wake Cycle) What substance is produced by hypothalamic
neurons that provide excitatory input to
other areas of the brain

A

Orexin

50
Q

Fatigue of neurons in the reticular
activating nuclei disrupts positive feedback
loop, allowing centers to actively
inhibit the cerebral cortex

A

Sleep

51
Q

What are the six physiological functions of sleep?

(Divided into nervous system and other functional systems)

A

Nervous System
1. Cognition
2. Neural maturation
3. Facilitation of learning and memory
4. Targeted erasure of synapses (i.e.,
“forgetting”)

Other Functional Systems:
5. Conservation of metabolic energy
6. Clearance of metabolic waste
products

52
Q

Electrical recordings from surface of
brain or scalp that reflect level of
excitation throughout the brain

A

Brain waves

Vary markedly between
wakefulness, sleep, and coma

53
Q

2 different nuclear structures of muscle spindles

A

Nuclear bag - multiple muscle fiber nuclei congregate in bags, which excites only primary afferent endings

Nuclear chain - multiple muscle fiber nuclei are aligned in a chain, which excites BOTH primary AND secondary afferent endings

54
Q

What are ranges of intensity and frequency of brain waves?

A

Intensity: 0-200 µV
Frequency: <1 – >50

55
Q

Explain the difference between synchronous and nonsynchronous brain waves

A

Synchronous: Concurrent firing of
neurons in synchrony with each other will
produce waves with higher voltage

Nonsynchronous: Concurrent firing of
neurons in opposite directions results in
opposing polarities and produces waves
with lower voltage

56
Q

What are the four types of brain waves?

A
  1. Alpha
  2. Beta
  3. Theta
  4. Delta
57
Q

What brain wave is present during
focused mental
activity, found in
frontal and parietal
areas?

What is the frequency of this type of wave?

A

Beta Waves

> 14 Hz

58
Q

What brain wave appears
during quiet
wakefulness,
primarily in the
occipital lobe?

What is the frquency and intensity?

A

Alpha Waves

8-13 Hz
~50 µV

59
Q

What brain wave is common in
children, linked to
emotional stress and
degenerative brain
states in adults?

What is the frequency?

A

Theta Waves

4-7 Hz

60
Q

What brain wave occurs in deep sleep, often
high amplitude?

What is the frequency?

A

Delta Waves

<3.5 Hz

61
Q

Two types of waves are involved in wakefulness:

Occurs during increased mental activty: _________
Occurs during decreased mental activity: ________

A

Increased mental activity: beta waves

Decreased mental activity: alpha waves

62
Q

Name the stages of NREM sleep and name the brain wave associated with the stage:

A

Stage 1: low-voltage with
intermittent ‘sleep
spindles’

Stage 2-3: theta waves

Stage 4: delta waves

63
Q

What brain waves occur during REM sleep?

A

Beta waves

64
Q

Muscle spindles with nuclei in “bags” excites which afferent endings?

A

Primary only

65
Q

Muscle spindles with nuclei in chains excite which afferent nerve endings?

A

Primary and secondary

66
Q

Primary afferent nerve endings are type _______ fibers that _________ the central portion of the muscle spindle

A

Ia
Encircles

67
Q

Secondary afferent endings are type ______ fibers that innervate areas ________ to primary afferent nerve endings

A

II
Lateral

68
Q

What type of motor nerve fibers innervate the ends of intramural fibers to control muscle tone?

A

Gamma motor nerve fibers

69
Q

What characterizes the dynamic responses of muscle spindles?

A

It is a rapid, short-lived response to changes in muscle LENGTH

Via primary afferent endings

70
Q

What characterizes the static response of muscle spindles?

A

Slow stretching of muscle spindles via primary AND secondary afferent endings for several minutes

71
Q

The static response of muscle spindles ensures smooth muscle movement over prolonged periods of stretch
True or false

A

True

72
Q

The dynamic response involves both primary and secondary afferent endings? true or false?

A

False
Only primary

73
Q

Define muscle stretch reflex

A

Excitation of muscle spindle causes reflex contraction of extrafusal skeletal muscle fibers, ensures smooth movement of muscles and prevents jerky movements

74
Q

Muscle stretch reflex is a _________ pathway formed between type ____ fiber from muscle sprinkles and anterior motor neuron which minimizes time delay for reflex action to occur

A

Monosynaptic

Ia

75
Q

Describe dynamic stretch reflex

A

Type Ia fibers rapidly but briefly transmit signals to oppose changes in muscle length

76
Q

Describe static stretch reflex

A

Type Ia and II fibers transmit signals to maintain constant degree of muscle contraction

77
Q

Describe Golgi tendon organ

A

Encapsulated sensory receptor that surrounds muscle tendon fibers

78
Q

Sensory and motor innervation of golgi tendon organ

A

Sensory: type Ib sensory afferent nerve fibers —> inhibitory interneurons —> anterior motor neurons —> prevents activation of anterior motor neurons

79
Q

The dynamic response of the Golgi tendon organ has intense reaction to ___________ _________ in tension

A

Sudden increases

80
Q

Static response of the Golgi tendon organ is a ______-______ firing that is proportional to to muscle tension

A

Steady-state

81
Q

What is the function of the Golgi tendon reflex

A

inhibitory reflex that prevents excessive muscle tension
Ex: someone throws a 50pound weight at you

82
Q

Type _____ fibers from Golgi tendon organ synapse with inhibitory ________ in dorsal horn which synapses with anterior motor neuron

A

Ib
Interneuron

83
Q

Explain the flexor reflex pathway and function

A

Sensory afferent nerve fibers transmit stimuli (nociceptive) to the interneuron pool in the dorsal horn which synapses with anterior motor neurons

Flexor muscles contract in response to sensory stimulus to coordinate flexión and abduction of the limb (withdrawal of the limb)

84
Q

Explain the 3 interneuron pools of the flexor reflex:
Diverging circuits
Reciprocal inhibition
Afterdischarge

A

Diverging: activate complimentary muscles
Reciprocal inhibition: inhibits antagonistic muscles
Afterdischarge: extends duration of reflex response

85
Q

Describe the pathway and function of the crossed extensor reflex

A

Sensory afferent nerve fibers transmits stimuli to the interneuron pool which synapses with anterior motor neuron on the contra lateral side of the spinal cord

Function: extensor muscles on the contra lateral side contract in response to sensory stimulus to coordinate muscle extension to maintain balance

86
Q

Describe the interneuron pool of crossed extensor reflex:
Afterdischarge

A

Extends duration of the reflex response

87
Q

Explain reciprocal inhibition and innervation

A

Reflex excitation of one muscle results in simultaneous inhibition of antagonistic muscles, ensures smoothness and efficient movements

Ex: flexor reflex and crossed extensor reflex

88
Q

3 reflexes of posture

A

Positive supportive reaction
Magnet reaction
Cord righting reflex

89
Q

Explain positive supportive reaction

A

Pressure on the footpad causes extension of the limb

90
Q

Explain the Magnet reaction

A

Pressure on one side of the footpad causes extension in that direction, preventing the animal from falling to that side

91
Q

Explain the cord righting reflex

A

Spinal animals laid on their side produce uncoordinated movements in attempt to raise the animal to standing position

92
Q

List 4 reflexes of locomotion

A

Stepping movements
Stumble reflex
Reciprocal stepping
Mark time reflex

93
Q

explain stepping movements reflex

A

Oscillation between reciprocal inhibition circuits controlling agonist and antagonistic movements cause rhythmical stepping of the limbs

94
Q

Explain the stumble reflex

A

Obstruction on top of foot will cause foot to stop, lift higher, and proceed forward

95
Q

Explain reciprocal stepping reflex

A

Forward movement of one limb causes backward movement of the opposite limb

96
Q

Explain mark time reflex

A

Diagonal stepping between all limbs occurs when animal is suspended and limbs dangle

ex: holding doggy over pool

97
Q

Explain scratch reflex

A

Initiated by itch/tickle —> position sense locates the point of irritation —> produces to-and-fro scratching (oscillatory movement)

98
Q

Muscle spasms result from _______ impulses

A

Pain

99
Q

mass reflex —> Strong pain or organ distensión produces sudden and profound activation of spinal cord

What 4 effects?

A

Flexor muscle spasm
Bladder/bowel evacuation
Increased arterial pressure
Profuse sweating

100
Q

3 possible causes for muscle cramping

A

Local irritation/metabolic abnormalities (severe cold, over exercise)
Broken bones - sharp edges produce pain —? Muscle spasm
Peritonitis —> abdominal muscle contraction

NURS 6413 Advanced Physiology and Pathophysiology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions