Question 1

REM sleep normally occurs for the first time:

Accepted Answer

REM sleep typically occurs about 70 to 90 minutes after sleep onset, and then recurs approximately every 90 minutes throughout the night.

Question 2

The reason that REM sleep occurs is:

Accepted Answer

The exact reason why REM sleep occurs is still not fully understood, making "unknown" the most accurate answer. While there are theories suggesting REM sleep plays a role in memory consolidation, problem-solving, and tension release, the definitive purpose of REM sleep remains a subject of ongoing research.

Question 3

What can sleep scientists say about people who do not get enough sleep?

Accepted Answer

Sleep deprivation can lead to an increase in cortisol, the stress hormone.

Question 4

The deeper stages of NREM sleep are characterized by:

Accepted Answer

The deeper stages of NREM sleep, such as stage 3 and 4, are characterized by slow brain waves called delta waves.

Question 5

Traditionally, there are _______________ stages of NREM sleep.

Accepted Answer

Traditionally, there are four stages of NREM sleep. These stages are distinguished based on the patterns of brain waves, with each stage being progressively deeper than the previous one.

Question 6

Your cousin Brenda says she is suffering several symptoms and claims they are due to premenstrual syndrome (PMS). Which of the following symptoms that she cites is the most questionably linked to the menstrual cycle?

Accepted Answer

The answer of Your cousin Brenda says she is suffering...

Question 7

James has been sleeping for about 90 minutes when his brain shows rapid, irregular waves. His blood pressure rises, his heart rate increases, and his skeletal muscles go limp. Which of the following is the most likely conclusion?

Accepted Answer

The rapid, irregular brain waves, increased heart rate and blood pressure, and limp muscles all indicate REM (rapid eye movement) sleep, which is characterized by physiological changes such as these. Since James has only been sleeping for 90 minutes, it is likely that he has just entered REM sleep for the first time in his sleep cycle. Therefore, option D is the most likely conclusion. Option A is incorrect because there is no evidence to suggest that James is chronically sleep-deprived or that his sleep during the day is abnormal. Option B is incorrect because the symptoms described are not consistent with the third stage of sleep. Option C is incorrect because physical activity during the day is not relevant to REM sleep.

Question 8

Chronic insomnia affects about _______________ of all adults.

Accepted Answer

Chronic insomnia affects about 10 percent of all adults. This condition is characterized by difficulty falling asleep, staying asleep, or experiencing non-restorative sleep for at least three nights a week for a minimum of three months, despite adequate opportunity for sleep.

Question 9

During sleep, periods of rapid eye movement (REM) alternate with non-REM sleep in a cycle that recurs about every:

Accepted Answer

The cycle of alternating periods of REM and non-REM sleep recurs about every 90 minutes. This cycle typically happens four to six times throughout the night.

Question 10

On an average, REM sleep periods last about _______________.

Accepted Answer

On average, REM sleep periods last about 20 minutes. REM sleep cycles, which are characterized by rapid eye movement and vivid dreaming, typically lengthen through the night, with the first cycle being the shortest and subsequent ones longer, but on average, a single REM period lasts around 20 minutes.

Question 11

During the night, which two types of sleep alternate with each other in cycles that take approximately 90 minutes?

Accepted Answer

During the night, REM (rapid eye movement) and NREM (non-rapid eye movement) sleep alternate with each other in cycles that take approximately 90 minutes. This cycle repeats several times throughout the night. REM sleep is characterized by rapid eye movements, muscle paralysis and vivid dreams, while NREM sleep is divided into 4 stages and is characterized by slow brain waves, reduced muscle activity and deep relaxation.

Question 12

When researchers studied whether or not dreaming occurs in non-REM sleep, they found that:

Accepted Answer

Researchers have found that dreaming occurs in non-REM sleep, but the dreams tend to be shorter and less vivid than those in REM sleep. This suggests that dreaming is not exclusive to REM sleep, but rather occurs throughout the sleep cycle.

Question 13

Judith is startled when her six-year-old daughter, Laura, sleepwalks into the family room. It is most likely that Laura is experiencing the _______________ stage of the sleep cycle.

Accepted Answer

Sleepwalking typically occurs during the deep stages of non-REM sleep, particularly in stages 3 and 4, with stage 4 being the deepest stage of sleep.

Question 14

Delta waves occur during:

Accepted Answer

Delta waves are high amplitude, low frequency waves that occur during NREM sleep, particularly during stages 3 and 4 which are also known as slow-wave sleep.

Question 15

During the night:

Accepted Answer

During the night, REM sleep periods become longer. This is because as the night progresses, the amount of deep sleep (NREM) decreases and the amount of lighter sleep (REM) increases.

Question 16

Periods of REM sleep alternate with periods of non-REM sleep in a cycle that recurs about every _______________ minutes.

Accepted Answer

The cycle of alternating periods of REM and non-REM sleep is approximately 90 minutes long. This cycle repeats throughout the night with each cycle becoming longer towards morning.

Question 17

_______________ are occasionally emitted by the brain in the third stage of non-REM sleep.

Accepted Answer

Delta waves are the slowest and highest amplitude brain waves and are associated with deep sleep, including the third stage of non-REM sleep.

Question 18

REM sleep has been called "paradoxical sleep" because:

Accepted Answer

REM sleep is called paradoxical sleep because the brain is highly active, almost as much as when we're awake, but the body is completely still and inactive. This is in contrast to NREM sleep, where the brain is less active but the body can still move and be restless.

Question 19

In _______________, a person experiences sudden unpredictable and irresistible attacks of sleepiness during the day.

Accepted Answer

Narcolepsy is a sleep disorder characterized by sudden and uncontrollable episodes of sleep during the day. These episodes can last from a few seconds to several minutes, and individuals with narcolepsy may fall asleep at inappropriate times, such as during a conversation or while driving.

Question 20

_______________ are the short bursts of rapid, high-peaking waves that the brain emits in the second stage of non-REM sleep.

Accepted Answer

Sleep spindles are the short bursts of rapid, high-peaking waves that the brain emits in the second stage of non-REM sleep. Alpha waves are low-frequency waves that occur when we are awake and relaxed, while delta waves are slower, high amplitude waves that occur during deep sleep. Neuro spindles is not a recognized term in the field of sleep research.

Quiz 5: Body Rhythms and Mental States