Deck 11: Biological Rhythms and Sleep

Question 1

If a hamster is kept in a laboratory and receives no information about changes in day length or temperature (i.e. housed in constant dark), its rhythms will eventually _______, with a daily cycle that lasts a bit longer than 24 hours.

A) persist, but only in males
B) become free-running
C) disappear
D) persist, but only in females

Answer 1

B

Question 2

The human menstrual cycle provides an example of a(n) _______ rhythm, because it repeats less than once per day.

A) infradian
B) ultradian
C) circadian
D) free-running

Answer 2

A

Question 3

In an experiment with hamsters, if a light with a timer is adjusted so that the light switches on and off 6 hours earlier than the animals are used to, they will show

A) period adjustment.
B) zeitgeber.
C) phase shift.
D) arrhythmia.

Answer 3

C

Question 4

The stimulus (usually the light-dark cycle) that entrains circadian rhythms is called a(n)

A) oscillating cycle.
B) phase marker.
C) zeitgeber.
D) biological rhythm.

Question 5

In the U.S., evidence that daylight affects human circadian rhythms is supported by the observation that even though everyone's time keepers (clocks, phone) report the same time, people in the western part of the time zone go to bed _______ people in the in eastern part of the time zone.

A) much earlier than
B) slightly earlier than
C) a bit later than
D) at the time as

Question 6

_______ is a symptom of a mismatch between internal and external time while traveling.

A) Entrainment
B) Zeitgeber
C) Jet lag
D) Free-run

Question 7

Destruction of the SCN _______ circadian rhythms of hormone secretion.

A) lengthens
B) abolishes
C) does not affect
D) shortens

Question 8

If an adult hamster with a 24-hour endogenous rhythm receives a lesion to the SCN and a subsequent SCN transplant from a young hamster with an endogenous rhythm of 20 hours, which outcome occurs?

A) The adult hamster will be arrhythmic.
B) The adult hamster will adopt a 20-hour rhythm.
C) The adult hamster will regain its original 24-hour rhythm.
D) The adult hamster will fail to entrain to the light-dark cycle.

Question 9

If SCN neurons are transplanted from animal A to animal B, and animal B previously had its SCN lesioned, animal B's rhythmicity will

A) disappear.
B) become abnormally short.
C) match animal A's rhythm.
D) become infradian.

Question 10

When deprived of time cues, people tend to show activity cycles that are

A) exactly 24 hours long.
B) a little less than 24 hours long.
C) a little more than 24 hours long.
D) completely unpredictable.

Question 11

The pineal gland of some birds and reptiles is referred to as a primitive "third eye" because

A) it feeds light information to the eye.
B) the skull over the pineal gland is especially thin, so it can sense light.
C) it secretes the hormone melatonin, which is a metabolite of a hallucinogen.
D) it is the only unilateral structure in the brain.

Question 12

Unlike in mammals, in birds the _______ is sensitive to light and may mediate entrainment of rhythms even after surgical removal of the eyes.

A) SCN
B) pituitary
C) pineal gland
D) thalamus

Question 13

Which statement is about the molecular clock is false?

A) The proteins Clock and Cycle bind to form a dimer.
B) The Clock/Cycle dimer enhances DNA transcription of the genes for Per and Cry.
C) Per and Cry inhibit the Clock/Cycle dimer.
D) Clock and Cycle proteins eventually break down and the 24 hour cycle begins again.

Question 14

People who tend to wake up in the morning with lots of energy likely carry a different version of the _______ gene than night owls, who stay up late at night and are drowsy in the morning.

A) Clock
B) per
C) cry
D) tau

Question 15

Because of shifts in circadian rhythms that occur around puberty, students at high schools that begin the school day after 8:30 am generally experience

A) increased levels of depression.
B) better academic performance.
C) lower school attendance.
D) faster growth rates.

Question 16

What is the primary evolutionary benefit of a circadian rhythm?

A) It allows an animal to better adjust to sudden, dramatic changes in the environment.
B) It allows an animal to incorporate a genetic program to dictate behavior.
C) It allows an animal to incorporate information about past important natural events and adjust its behavior accordingly.
D) It allows an animal to anticipate an important natural event and adjust its behavior accordingly.

Question 17

In a young adult, during the course of a night's sleep the length of the bouts of _______ sleep progressively decrease, while the length of bouts of _______ sleep progressively increase.

A) stage 3 SWS; REM
B) stage 1; stage 3 SWS
C) stage 2; REM
D) REM; state 3 SWS

Question 18

Stage 3 sleep (SWS) is characterized by

A) the periodic appearance of spindles.
B) low-voltage, high-frequency scalp EEG activity.
C) slow waves with a frequency of 10 Hz.
D) large-amplitude delta waves.

Question 19

Dreams experienced during REM sleep are characterized by

A) vague visual imagery.
B) a lack in intellectual content.
C) realistic visual imagery.
D) complicated story lines.

Question 20

Flaccidity in the large muscles of the body is associated most commonly with _______ sleep.

A) stage 1
B) stage 3
C) REM
D) Both a and b

Question 21

If you recall a vivid dream as you wake up, you likely to have been in _______ sleep just before awakening.

A) stage 1
B) stage 2
C) stage 3
D) REM

Question 22

A child wakes suddenly after sleeping for a couple of hours, is terrified and shows significant autonomic activity, such as a racing heart rate and dilated pupils. When questioned, the child cannot remember what frightened her. It is likely the child has just woken from _______ sleep.

A) stage 1
B) stage 2
C) stage 3
D) REM

Question 23

The characteristic EEG recording obtained from subjects who are relaxed with their eyes closed is called the

A) alpha.
B) beta.
C) delta.
D) gamma.

Question 24

Frightening dreams associated with stage 3 sleep are called

A) nightmares.
B) night terrors.
C) vertex spikes.
D) night spindles.

Question 25

How do dolphins sleep if they must regularly come to the water's surface to breathe?

A) Only one brain hemisphere sleeps at a time.
B) Both hemispheres sleep at the same time but the sleep is light.
C) They retain air in their lungs and stay at the surface to breath while sleeping.
D) They do not come to the surface while sleeping, but instead obtain oxygen through their skin.

Question 26

Infant sleep is characterized by _______ sleep cycles than those of adults, with proportionally more _______ sleep.

A) deeper; stage 1
B) shorter; REM
C) longer; stage 2
D) longer; stage 3

Question 27

Newborn infants spend as much as _______ % of their sleep time in REM sleep.

A) 5
B) 20
C) 50
D) 80

Question 28

A woman has just celebrated her 100^th birthday. Which description of her sleep is mostly likely to be true?

A) She still enjoys sleeping in until 9 am most days.
B) Long periods of REM sleep in her usual sleep cycle.
C) An EEG of her brain would reveal the complete absence of stage 3 sleep.
D) She routinely has a problem with falling asleep, but once asleep she stays asleep until morning.

Question 29

The large proportion of _______ sleep seen in infancy suggests it is necessary for nervous system maturation.

A) stage 1
B) stage 2
C) stage 3
D) REM

Question 30

Prolonged sleep deprivation (around 8 days) can lead to all of the following except

A) hallucinations and disorientation.
B) difficulty concentrating.
C) increases in irritability.
D) a strengthened immune system.

Question 31

Depending on the definition used for insomnia, its prevalence ranges from _______ in the adult population.

A) 2% to 20%
B) 5% to 30%
C) 10% to 40%
D) 20% to 60%

Question 32

Which statement about fatal familial insomnia is false?

A) Autopsy of patients with this disorder shows degeneration in the cortex and thalamus.
B) It is characterized by chronic lifetime insomnia.
C) It is caused by a defect in the gene for a prion protein.
D) People with this disorder show diffuse bacterial infections.

Question 33

Experimental evidence suggests that the biological role of SWS and REM sleep may be related to the

A) consolidation of perceptual learning.
B) effort to shed bad memories.
C) processing of intense sexual excitement.
D) problem-solving activities of the brain.

Question 34

Sleep that immediately follows a period of learning has the apparent effect of

A) blocking long-term retention.
B) improving long-term retention.
C) undoing the learning.
D) impairing retrieval of the learned material.

Question 35

Which mechanism has not been identified as a biological function of sleep?

A) Energy conservation
B) Niche adaptation
C) Restoration of brain and body
D) Brain rest

Question 36

The _______ system is responsible for promoting REM sleep.

A) pontine
B) forebrain
C) brainstem
D) hypothalamic

Question 37

The isolated forebrain preparation involves a cut through the

A) spinal cord.
B) medulla.
C) midbrain.
D) thalamus.

Question 38

The cortical EEG pattern of the isolated forebrain animal is characterized by

A) sustained SWS.
B) ongoing arousal.
C) alternating periods of arousal and sleep.
D) intense seizure activity.

Question 39

What is the significance of the finding that the isolated brain exhibits signs of alternating between wakefulness, SWS, and REM sleep?

A) It showed that in an isolated brain sleep is erratic and unpredictable.
B) It showed that the systems for controlling sleep are very simple.
C) It showed that that systems for controlling sleep are located in the brain.
D) It showed that systems for controlling sleep are not located in the brain.

Question 40

A scientist wants to conduct a study in which an animal brain is transected but REM sleep could continue to be measured in the cerebral cortex. Which region must remain connected to the cortex?

A) Basal forebrain
B) Optic chiasm
C) Spinal cord
D) Pons

Question 41

Research has shown that in the forebrain system, SWS is promoted through the actions of GABA on the _______, while in the brainstem system, the _______ projects axons to the brain, promoting wakefulness.

A) tuberomammillary nucleus; locus coeruleus
B) tuberomammillary nucleus; reticular formation
C) locus coeruleus; coeruleus
D) locus coeruleus; reticular formation

Question 42

A lesion made to the reticular formation will result in a cortical EEG pattern of

A) sustained sleep.
B) intense arousal.
C) arousal and sleep in alternating periods.
D) intense seizure activity.

Question 43

Norepinephrine innervation to the brain comes primarily from the

A) tuberomammilary nucleus.
B) locus coeruleus.
C) reticular formation.
D) basal forebrain.

Question 44

Small lesions near the pontine REM sleep center _______ the loss of motor inhibition during REM sleep.

A) increase
B) abolish
C) diminish
D) have no effect on

Question 45

Electrical stimulation of the _______ can induce SWS activity.

A) basal forebrain
B) optic chiasm
C) thalamus
D) reticular formation

Question 46

The region that appears to be responsible for activating wakefulness is known as the

A) basal forebrain.
B) optic chiasm.
C) locus coeruleus.
D) reticular formation.

Question 47

Many people with narcolepsy also exhibit _______, in which muscle tone is suddenly lost without loss of _______.

A) atonia; sleep
B) cataplexy; consciousness
C) sleep-onset insomnia; REM sleep
D) sleep apnea; snoring

Question 48

REM behavior disorder (RBD) may be reduced by drugs that

A) reduce pain.
B) prevent REM sleep.
C) prevent stage 3 sleep (SWS).
D) reduce anxiety.

Question 49

In humans, somnambulism usually occurs during _______ sleep.

A) stage 1
B) stage 2
C) stage 3
D) REM

Question 50

People diagnosed with sleep apnea show all of the following symptoms except

A) frequent awakenings.
B) snoring.
C) an abundance of REM sleep.
D) low oxygen levels during sleep.

Question 51

It has been speculated that sudden infant death syndrome (SIDS) may be a consequence of a form of

A) sleep paralysis.
B) sleep apnea.
C) insomnia.
D) REM behavior disorder.

Question 52

The incidence of insomnia is greatest in _______ in general, and in both men and women in _______.

A) women; the later stages of life
B) men; the later stages of life
C) women; middle age
D) men; middle age

Question 53

The type of rhythmicity characterized by the regular, predictable onset of a particular behavior once a day is called a(n) _______ rhythm.

Question 54

The process by which an animal slowly shifts its circadian rhythm to synchronize with the time of sunrise each day is called _______.

Question 55

The hormone _______ has been especially implicated in informing the brain about day length?

Question 56

A sleeping person whose EEG shows vertex spikes is in the phase of _______ sleep.

Question 57

The EEG of a person in _______ sleep is characterized by brief periods of sleep spindles and K complexes.

Question 58

The EEG of a sleeping person is desynchronized, their limbs are flaccid, and their eyes are darting under closed eyelids; this person is in _______ sleep.

Question 59

In a person who is sleeping, _______ sleep shows periodic bursts of 12‒14 Hz brain activity in an EEG recording.

Question 60

The brain region called the _______ promotes stage 3 sleep (SWS), and lesions to this region induce insomnia.

Question 61

The brain region called the _______ promotes REM sleep in large part by preventing motor neurons from firing.

Question 62

Sleep _______ is treated with vasopressin, which reduces urine production.

Question 63

Differentiate circadian, ultradian and infradian rhythms, and provide an example of each.

Question 64

Create a short paragraph using the following terms: zeitgeber, entrainment, free-run, and phase shift

Question 65

Researchers in one study transplanted the SCN of a fetal hamster with the tau mutation into the hypothalamus of a nonmutant adult hamster with a lesioned SCN. What was the purpose of this study, and what was the outcome?

Question 66

Explain how gene mutations in tau and Clock affect circadian rhythms.

Question 67

Which characteristic EEG pattern is seen during stage 2 sleep?

Question 68

How do REM sleep and total sleep change across the lifespan?

Question 69

Explain the niche adaptation concept of the biological function of sleep.

Question 70

Briefly summarize the four neural systems that underlie sleep.

Question 71

Why might it be risky to sleep with someone who has been diagnosed with REM behavior disorder (RBD)?

Question 72

Compare and contrast sleep-onset insomnia and sleep-maintenance insomnia.

Question 73

Describe research observations of mammals that indicate the existence of an endogenous clock.

Question 74

Explain, using a diagram, the molecular basis of the circadian clock.

Question 75

Name and describe the sleep stages of humans, including descriptions of EEG recordings and behavioral observations for each stage.

Question 76

Describe the sleep patterns of infants, adults, and elderly people. Discuss why sleep patterns may change across the lifespan.

Question 77

Describe the effects of long-term sleep deprivation on human health and performance.

Question 78

Outline the four hypotheses that attempt to explain the biological function of sleep, citing research evidence in each case.

Question 79

Give an overview of the connections between sleep and learning, citing experimental evidence in your answer.

Question 80

Describe the four interacting neural systems that underlie sleep.