Chapter 10

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

phase shift.

The _______ system is responsible for promoting REM sleep.

pontine

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

reticular formation.

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

sleep apnea.

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.

stage 3

Slow, large-amplitude waves are seen in the EEG records of people who are in _______ sleep.

stage 3

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.

stage 3 SWS; REM

In humans, enhanced serum levels of growth hormone are evident during

stage 3 sleep (SWS).

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

sustained SWS.

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

50

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

the skull over the pineal gland is especially thin, so it can sense light.

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

10% to 40%

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

Brain rest

Electrical stimulation of the reticular formation leads to immediate

Awakening

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

Jet lag

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

Only one brain hemisphere sleeps at a time.

Nightmares are associated with _______ sleep.

REM

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

REM

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?

The adult hamster will adopt a 20-hour rhythm.

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 bit later than

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

a little more than 24 hours long.

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

a strengthened immune system.

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

abolish

Destruction of the SCN _______ circadian rhythms of hormone secretion.

abolishes

The pattern of sleep in elderly people is characterized by increases in

awakenings

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.

become free-running

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

consolidation of perceptual learning.

Stage 3 sleep (SWS) is especially prominent during the _______ of a night's sleep.

initial half

Stage 3 sleep (SWS) is characterized by

large-amplitude delta waves.

Norepinephrine innervation to the brain comes primarily from the

locus coeruleus.

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

match animal A's rhythm.

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.

Clock

What is the primary evolutionary benefit of a circadian rhythm?

It allows an animal to anticipate an important natural event and adjust its behavior accordingly.

In the absence of light cues, hamsters with two copies of the tau mutation will show biological rhythms with periods of _______ hours.

about 20

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

sustained sleep.

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

ultradian

In the typical sleep pattern of healthy adults, the first REM period of the night may last a few minutes while the last REM period may last

up to 40 minutes.

Dreams experienced during REM sleep are characterized by

vague visual imagery.

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

women; the later stages of life

The external cue that animals use to discern the time of day is called a

zeitgeber