Deck 8: Wakefulness and Sleep

Question 1

The mean preferred time of going to sleep gets later and later until about age 20 and then starts a gradual reversal.​

Answer 1

True

Question 2

A human's body temperature over the course of 24 hours is usually highest ____.​

A)about the time of awakening
B)​mid-morning
C)​mid to late afternoon
D)in the middle of the night

Answer 2

​mid to late afternoon

Question 3

The dominant zeitgeber for land animals is light.​

Answer 3

True

Question 4

Biological clocks are very resistant to environmental influences.​

Question 5

Animals produce endogenous circadian rhythms that last ____.​

A)about an hour
B)​about a day
C)​about a week
D)more than a day

Question 6

Bright light late in the afternoon shortens the circadian rhythm.​

Question 7

After removing all sensory input to the brain,an animal would continue to have periods of sleep and wakefulness.​

Question 8

What does "endogenous" mean?​

A)occurring at regular intervals
B)​more likely to be learned
C)​sensitive to light/dark patterns
D)generated from within

Question 9

​Suppose you fell into a cave and lost your watch.Without any time cues,your circadian rhythm would ____.

A)increase dramatically over time
B)​cease to exist
C)​decrease over time
D)remain relatively stable

Question 10

Which of the following is most clearly under the control of a circadian rhythm in most animals?​

A)sleep
B)​storage of body fat
C)​migration
D)mating

Question 11

Dreams only occur during REM sleep.​

Question 12

Orexin is not necessary for waking up,but it is for staying awake.​

Question 13

Melatonin is released by the SCN.​

Question 14

The activation-synthesis theory of dreams argues that dreams are the result of random brain activity.

Question 15

Blind and deaf animals do not have circadian rhythms.​

Question 16

Young children are more likely to be "morning people" than older adults.​

Question 17

Alternation between wakefulness and sleep depends completely on stimuli in the environment.​

Question 18

Temporary sleep deprivation causes the body to respond in a similar manner as it does to being ill.​

Question 19

Sleep apnea is characterized by sleep attacks during wakefulness.​

Question 20

The biological clock depends on part of the hypothalamus,called the suprachiasmatic nucleus.​

Question 21

The suprachiasmatic nucleus is found in the ____.​

A)substantia nigra
B)​caudate nucleus
C)​thalamus
D)hypothalamus

Question 22

Which of the following would most likely help someone adjust to jet lag?​

A)taking a nap during the day
B)​taking melatonin when you need to wake up
C)​keeping the room light when you need to stay awake
D)darkening the room when you need to stay awake

Question 23

Which statement is TRUE with regard to the duration of a self-generated sleep/activity cycle?​

A)It is unreliable in most species, and dependably close to 24 hours only in primates.
B)​It is longer if the organism is normally active in the dark.
C)​It rarely varies from one individual to another, if at all.
D)It is highly consistent in a given individual in a given environment.

Question 24

Social stimuli - that is,the effects of other people - are weak ____,unless they induce exercise or other vigorous activity.​

A)effects
B)​motivators
C)​rhythms
D)zeitgebers

Question 25

A "zeitgeber" is a(n)____.​

A)biological clock
B)​animal that does not have a biological clock
C)​environmental cue that resets a biological clock
D)body activity that is controlled by a biological clock

Question 26

Based on research,it has been determined that the human circadian rhythm appears to be ____.​

A)shorter than 24 hours
B)​exactly 24 hours
C)​just over 24 hours
D)closer to 28 hours

Question 27

What is the principal zeitgeber for land animals?​

A)light
B)​the tides
C)​temperature
D)barometric pressure

Question 28

When traveling across time zones,how does the direction of travel affect one's adjustment to the new time zone?​

A)Travel to the east is easier.
B)​Travel to the west is easier.
C)​The direction of travel makes no difference.
D)The effect varies greatly from person to person.

Question 29

After damage to the suprachiasmatic nucleus,the body ____.​

A)cannot generate biological rhythms
B)​still has rhythms in synchrony with environmental patterns of light and dark
C)​still has rhythms, but they are less consistent
D)still has rhythms, but they can only be reset by artificial light

Question 30

Research on circadian rhythms has shown that one of the best ways to increase the alertness and efficiency of workers on night shifts is to ____.​

A)expose them to bright lights while they work
B)​keep the environmental temperature constant from night to day
C)​have them eat a big meal before going to sleep
D)allow them to catnap

Question 31

When studying disruptions to the biological clock in animals,what did Curt Richter find?​

A)Blinding animals strongly disrupted their clock.
B)​Rendering animals deaf strongly disrupted their clock.
C)​Long periods of forced activity strongly disrupted the clock.
D)The biological clock is insensitive to most forms of interference.

Question 32

A person's circadian activity cycle would most likely drift out of phase with the activity of other people if the person ____.​

A)spends a period of time in the wilderness, away from clocks
B)​habitually eats a big meal just before bedtime
C)​spends a period of time in seclusion, away from sunlight
D)lives near the equator, where the seasons do not vary

Question 33

Suppose you work on a submarine with only artificial light.You are required to follow a schedule of working for 12 hours and then sleeping for 6.What rhythm,if any,will your alertness and body temperature show?​

A)They will follow a rhythm of 18 hours.
B)​They will follow the usual rhythm of 24 hours.
C)​They will follow a rhythm of 21 hours.
D)They will cease to show any consistent rhythm.

Question 34

If suprachiasmatic nucleus neurons are disconnected from the rest of the brain,they ____.​

A)no longer produce any activity
B)​continue to produce activity that follows a circadian rhythm
C)​produce a 20-hour rhythm
D)produce spontaneous bursts of activity, but on no rhythmic pattern

Question 35

​A disruption of circadian rhythms due to crossing time zones is known as ____.

A)circashift
B)​phaselag
C)​jetlag
D)zeitgeber

Question 36

What happens after damage to the suprachiasmatic nucleus itself?​

A)Light no longer resets the biological clock, but the animal continues generating a 24-hour rhythm.
B)​Animals' activity patterns become less consistent and no longer respond to light and dark cycles.
C)​Animals lose their biological rhythms of temperature, but keep other circadian rhythms.
D)Animals begin to maintain a constant level of activity throughout the 24-hour day.

Question 37

Mammals have circadian rhythms ____.​

A)only for their sleep/activity cycle
B)​only for frequency of eating and drinking
C)​for sleep and body temperature only
D)for a variety of activities, including sleep

Question 38

An astronaut orbiting earth experiences 45-minute periods of daylight alternating with 45-minutes periods of darkness.What is likely to happen? ​

A)The alternating patterns allow for normal rhythm development.
B)​They are fully alert during wakeful periods.
C)​They are able to sleep during rest periods.
D)They sleep poorly during rest periods.

Question 39

What is the role of the suprachiasmatic nucleus in circadian rhythms?​

A)Its neurons generate a 24-hour rhythm by themselves.
B)​Its neurons can reset the biological clock, but they do not generate it.
C)​It relays visual information to the biological clock.
D)It relays information from the biological clock to areas that control temperature and activity.

Question 40

The SCN produces circadian rhythms by altering ____.​

A)blood pressure
B)​production of proteins
C)​action potential velocity
D)axon myelination

Question 41

​The SCN is located just above the ____.

A)optic chiasm
B)​thalamus
C)​hypothalamus
D)visual cortex

Question 42

Someone in a(n)____ state alternates between periods of sleep and moderate arousal,although even during the more aroused state,the person shows no awareness of surroundings and no purposeful behavior.​

A)unconscious
B)​minimally conscious
C)​coma
D)vegetative

Question 43

A polysomnograph displays ____.​

A)action potentials of individual neurons
B)​a combination of EEG and eye-movement records
C)​the rate of glucose uptake in active regions of the brain
D)the electrical resistance of the scalp

Question 44

Alpha waves are characteristic of what type of activity?​

A)NREM sleep
B)​nightmares
C)​relaxed wakefulness
D)periods of great excitement

Question 45

What do the EEG waves look like when brain activity is "desynchronized"?​

A)long, slow waves of large amplitude
B)​short, rapid waves of large amplitude
C)​regular alternation between waves of large amplitude and waves of small amplitude
D)irregular waves with low amplitude

Question 46

EEG waves are larger when brain activity decreases because ____.​

A)the EEG measures muscle tension, which also decreases
B)​neurons are becoming more synchronized
C)​neurons are becoming more desynchronized
D)blood flow is increasing

Question 47

With each succeeding stage of sleep (from 1 to 4),____.​

A)breathing and heart rates increase
B)​brain activity increases
C)​slow, large-amplitude waves increase in number
D)brain waves become smaller

Question 48

The pineal gland releases the ____ hormone,which influences both circadian and circannual rhythms.​

A)androgen
B)​melanopsin
C)​melatonin
D)estrogen

Question 49

Researchers have demonstrated that the expression of the SCN genes can be changed through ____.​

A)exposure of the eyes to light
B)​barometric pressure
C)​the diet
D)morning exercise

Question 50

The PER and TIM proteins accumulate during the day until they cause sleepiness.What prevents them from continuing to accumulate at night?​

A)Metabolic rates increase at night, so proteins are digested faster than they can be synthesized.
B)​The high levels of melatonin present at night react with the proteins to disable them.
C)​The proteins are unstable at the lower body temperatures that are typical at night.
D)When the proteins reach a high level, they turn off the genes that produce them.

Question 51

The circadian rhythm is reset by input from special ganglion cells in the retina.These ganglion cells are unusual in that they ____.​

A)receive input from only cones, not rods
B)​are located only in a doughnut-shaped band surrounding the fovea
C)​respond directly to light, but respond very slowly
D)become active only at night or in very dim light

Question 52

A small branch of the optic nerve,known as the ____ path extends directly from the retina to the SCN.​

A)opticthalamic
B)​retinohypothalamic
C)​opticretinal
D)retinothalamic

Question 53

After isolating a neuron from the rest of the brain,you find that it has a moderately stable circadian rhythm.The most likely home of this neuron is in the ____.​

A)optic nerve
B)​MPOA
C)​SCN
D)pineal gland

Question 54

Slow-wave sleep is comprised of ____.

A)alpha wave sleep
B)​stages 1 and 2
C)​stages 3 and 4
D)REM sleep

Question 55

When do the secretions of melatonin begin?​

A)just before a person awakens
B)​when body temperature is at its lowest
C)​when body temperature is at its highest
D)a couple of hours before a person naturally falls asleep

Question 56

What is paradoxical about paradoxical sleep?​

A)It serves restorative functions, and yet the body has no apparent need for it.
B)​it is light sleep in some ways and deep sleep in other ways
C)​It depends on serotonin for its onset and acetylcholine for its offset.
D)It is associated with dreaming although brain activity is low.

Question 57

The input from the eyes to the suprachiasmatic nucleus,responsible for shifting the phase of the circadian rhythm,originates from ____.​

A)cones only
B)​ganglion cells that are not connected to any cones or rods
C)​cones and rods equally
D)rods only

Question 58

Sleep spindles and K-complexes are most characteristic of which sleep stage?​

A)stage 1
B)​stage 2
C)​stage 3
D)stage 4

Question 59

The proteins PER and TIM,originally discovered in insect but now found in mammals also,influence circadian rhythms by ____.​

A)building up during the day and declining during sleep
B)​being transformed into melatonin
C)​stimulating and inhibiting (respectively) the release of acetylcholine in the cerebral cortex
D)providing negative feedback from the muscles to the neurons that innervate them

Question 60

An electroencephalograph displays ____.​

A)action potentials of individual neurons
B)​a net average of all the neurons' potentials
C)​the rate of glucose uptake in active regions of the brain
D)the electrical resistance of the scalp

Question 61

Typically,a person who falls asleep enters ____.​

A)stage 4 and slowly progresses through the stages 3, 2, 1 and then REM
B)​REM and then slowly progresses from stage 4, to 3, then 2, and lastly 1
C)​stage 1 and slowly progresses through stages 2, 3 and 4, but not necessarily in order
D)stage 1 and slowly progresses through stages 2, 3 and 4 in order

Question 62

In response to emotionally arousing events,the locus coeruleus releases ____.​

A)norepinephrine
B)​acetylcholine
C)​dopamine
D)serotonin

Question 63

After entering stage 4 for the first time each evening,the sleeper typically ____.​

A)returns immediately to stage 1
B)​enters REM
C)​cycles back through stages 3 and 2
D)wakes up

Question 64

The ____ is a structure that extends from the medulla into the forebrain.​

A)reticular formation
B)​tectum
C)​tegmentum
D)thalamus

Question 65

During REM sleep,the EEG shows ____.​

A)regular, high-voltage slow waves
B)​irregular, high-voltage slow waves
C)​regular, low-voltage slow waves
D)irregular, low-voltage fast waves

Question 66

Some drugs used to treat allergies may produce drowsiness if they ____.​

A)block histamine
B)​stimulate acetylcholine
C)​decrease adenosine
D)block GABA

Question 67

Sometimes people find themselves unable to move their postural muscles immediately after awakening Why?

A)Blood pressure is too low.
B)​The motor nerves are inactive until body temperature reaches its normal level.
C)​An increase in light striking the eyes reflexively inhibits the motor neurons.
D)Part of the brain is still asleep.

Question 68

In comparison to NREM dreams,REM dreams ____.​

A)are less likely to include striking visual imagery
B)​are more likely to include complicated plots
C)​do not contain violence
D)are almost always less than five minutes

Question 69

What is the best way to determine if an individual who claims to never dream does,in fact,have dreams?​

A)Ask them about their dreams immediately after they wake up in the morning.
B)​Wake them up during REM sleep and ask them if they have been dreaming.
C)​Wake them up during NREM sleep and ask them if they have been dreaming.
D)Ask them under hypnosis if they have had any dreams recently.

Question 70

REM sleep is characterized by which of the following?​

A)tension and activity of the postural muscles
B)​low and steady heart and breathing rates
C)​a high level of brain activity
D)a highly synchronized EEG pattern

Question 71

After a cut through the midbrain separates the forebrain and part of the midbrain from all the lower structures,an animal ____.​

A)stops sleeping
B)​sleeps a normal amount per day, but lacks REM sleep
C)​enters a prolonged state of sleep
D)alternates rapidly between sleep and wakefulness

Question 72

Compared to the earlier part,the later part of a night's sleep ____.​

A)includes a larger percentage of REM sleep
B)​includes a lower percentage of REM sleep
C)​is characterized by declining body temperature
D)has more slow wave sleep

Question 73

The role of the reticular formation in arousal is that it is ____.​

A)the single, critical system in arousing the cortex
B)​only one of several systems involved in arousal
C)​activated only by external stimuli
D)activated only by internal stimuli

Question 74

Cells in the basal forebrain increase arousal and wakefulness by releasing ____.​

A)norepinephrine
B)​acetylcholine
C)​dopamine
D)serotonin

Question 75

For a normal person,about how long does a cycle of sleep (from stage 1 to stage 4 and back again)last?​

A)10 minutes
B)​90 minutes
C)​4 hours
D)7 hours

Question 76

Stimulation of the pontomesencephalon ____.​

A)awakens a sleeping individual
B)​decreases alertness in someone already awake
C)​shifts the EEG from short waves to long, slow waves
D)delays the onset of the next REM period

Question 77

Orexin,produced by neurons in the hypothalamus,appears to be necessary for ____.​

A)getting to sleep
B)​waking up
C)​raising body temperature
D)staying awake

Question 78

The relationship between sleep stage and dreaming is that dreams ____.​

A)occur only in REM sleep
B)​occur only in NREM sleep
C)​are more frequent and more vivid in REM sleep
D)are more frequent and more vivid in NREM sleep

Question 79

One part of the reticular formation that contributes to cortical arousal is known as the ____.​

A)tectomesencephalon
B)​pontomesencephalon
C)​corticomesencephalon
D)rubromesencephalon

Question 80

With regard to sleep and arousal,the locus coeruleus is ____.​

A)very active during sleep
B)​active when the pontomesencephalon is not
C)​almost completely inactive during sleep
D)instrumental in waking us up