Page 101 - 2024-bfw-MyersAP4e

Module 1.5b

• Leaving the alpha waves of the awake, relaxed stage, • Being bathed in (or deprived of) light disrupts our 24-hour
we descend into the irregular brain waves of Stage 1 biological clock. People who are chronically deprived of
sleep, the first non-REM (NREM) sleep stage, which is natural sunlight, such as night-shift workers, may experi-
often associated with hallucinations. ence desynchronization.
• Stage 2 sleep (in which we spend about half our sleep • Artificial light, including that from light-emitting elec-
time) follows, with its characteristic sleep spindles. tronic devices, delays sleep and affects sleep quality.
• We then enter Stage 3 sleep, lasting about 30 minutes,
with large, slow delta waves. 1.5-7 What are sleep’s functions?
• About an hour after falling asleep, we ascend from our
initial sleep dive and begin periods of REM (rapid eye • Sleep may have played a protective role in human evolu-
Distributed by Bedford, Freeman & Worth Publishers. Not for redistribution.
movement or R) sleep. REM sleep, which includes most tion by keeping people safe during potentially dangerous
dreaming, is described as a paradoxical sleep stage periods.
because it features internal arousal but external calm • Sleep helps restore the immune system and repair dam-
(near paralysis). aged neurons.
Copyright © Bedford, Freeman & Worth Publishers.
• During a normal night’s sleep, Stage 3 sleep shortens and • Sleep consolidates our memories by replaying recent
REM and Stage 2 sleep lengthens. learning and strengthening neural connections.
• Sleep promotes creative problem solving the next day.
1.5-6 How do biology and environment interact in
our sleep patterns? • During slow-wave sleep, the pituitary gland secretes
human growth hormone, which is necessary for muscle
• Biology — our circadian rhythm as well as our age and our development.
body’s production of melatonin (influenced by the brain’s • Sleep conserves energy, helping us preserve it for when
suprachiasmatic nucleus) — interacts with social, cultural, we need it most.
and economic influences and individual behaviors to
determine our sleeping and waking patterns.

®
AP Practice Multiple Choice Questions
1. Which of the following psychological concepts refers to 3. Which body chemical is most implicated in Dr. Liza’s
a student’s biological clock’s sleep–wake pattern that research?
follows a 24-hour cycle? a. Dopamine c. Norepinephrine
a. Melatonin b. Melatonin d. Epinephrine
b. Circadian rhythm 4. If Dr. Liza finds that the group who scrolled through their
c. Suprachiasmatic nucleus friends’ photos on social media took longer to fall asleep
d. Rapid eye movement sleep
than the other group, what conclusion can she draw?
Use the following text to answer questions 2–5: a. Scrolling through friends’ photos on social media
caused the volunteers to take longer to fall asleep.
Dr. Liza conducted a sleep study in which half of the
volunteers were randomly assigned to scroll through their b. There is a positive correlation between scrolling
friends’ photos on social media right before bedtime. The through friends’ photos on social media and the
other half of the volunteers were told to avoid screens at length of time it took the volunteers to fall asleep.
bedtime. Dr. Liza measured the length of time it took for the c. The effect of social media usage prior to bedtime can
volunteers to fall asleep once they got into their beds. be applied to the general population.
d. Dr. Liza cannot draw any conclusions about this
2. Which brain area is the likely focus of Dr. Liza’s research? research given its qualitative nature.
a. Hippocampus c. Suprachiasmatic nucleus
b. Cerebellum d. Motor cortex

Sleep: Sleep Stages and Theories Module 1.5b 101

03_myersAPpsychology4e_28116_ch01_002_163.indd 101 15/12/23 9:24 AM