Ch 14- Sleep, Dreaming and Circadian Rhythms

Question 1

What are the 3 standard psychophysiological measures of sleep

Answer 1

• EEG, EOG and EMG

Question 2

Explain stage 1 of EEG sleep

Answer 2

• As a person prepares to sleep, eyes shut and alpha waves being to punctuate the low voltage high frequency waves of alert wakefulness
• then, as the person transitions into stage 1 there is a low voltage, high frequency signal slower than alert wakefulness

Question 3

Explain stage 2 of EEG sleep

Answer 3

• gradual increase in EEG voltage and a decrease in frequency
• slightly higher amplitude and lower frequency than stage 1
• ## K complexes and sleep spindles

Question 4

Explain K complexes in stage 2 sleep

Answer 4

single large negative wave (upward deflection) followed immediately by a single large positive wave (downward deflection)

Question 5

Explain sleep spindles in stage 2 sleep

Answer 5

0.5-2 sec waxing and waning burst of 11-15 Hz waves

Question 6

Describe stage 3 EEG sleep

Answer 6

• defined by predominance of delta waves (largest and slowest EEG waves), 2Hz

Question 7

Explain emergent stage 1 sleep

Answer 7

• after staying in stage 3 for a while, the person cycles back into stage 1
• this time, emergent stage 1 EEG are marked by rapid eye movements (REMs) and a loss of tone in the muscles

Question 8

How long does each sleep cycle tend to be?

Answer 8

90 minutes, as the night progresses, more time is spent in emergent stage 1 and less time in stage 3

Question 9

Stage 3 sleep is often referred to as

Answer 9

slow wave sleep or NRM3 (non rem sleep)

Question 10

Summary of sleep stages

Answer 10

REM sleep- emergent stage 1

NREM:
- initial stage 1 (NREM1)
- stage 2 (NREM2)

Slow wave sleep:
stage 3 (NREM3)

Question 11

Kleitman’s discovery of REM sleep and dreaming

Answer 11

• woke up subjects during REM sleep and found that 80% could clearly recall a dream they were just having (told it like a narrative)
• but only 7% of awakenings from NREM sleep led to dream recall (isolated experiences)

Question 12

5 common beliefs about dreaming

Answer 12

external stimuli and dreams, dream duration, ppl who don’t dream, sexual content in dreams, sleepwalking/talking

Question 13

explain external stimuli and dreams

Answer 13

• Dement and Wolport sprayed water on sleeping volunteers after they had been in REM for a few minutes then awoken
• in 14 out of 33 cases, the water was incorporated into the dream report
• some stimuli is more likely than others to be incorporated into a dream, such as pressure of a limb

Question 14

describe dream duration

Answer 14

• dreams run in real time
• Dement: participants were awoken 5 or 15 minutes after beginning REM episode and asked to decide if they had been dreaming for 5 or 15 mins,
• found that they were correct 92/111 times
• dreams run slightly slower than real time

Question 15

explain sexual content in dreams

Answer 15

• penile erections occur at the same rate in non sexual dreams as well

Question 16

explain sleep walking/talking

Answer 16

sleep talking has no association with REM and can occur any cycle, occurs during transition to wakefulness

sleep walking occurs during slow wave sleep and never during REM bc muscles are too relaxed here

Question 17

what is the term for sleep walking?

Answer 17

somnambulism

Question 18

what is the term for sleep talking?

Answer 18

somniloquy

Question 19

T or F: dreaming can occur during NREM sleep as well?

Answer 19

T

Question 20

what is lucid dreaming?

Answer 20

the ability to be consciously aware that one is dreaming and to be able to control the content of the dream

Question 21

Freud thoughts on dreams and manifest vs latent dreaming

Answer 21

dreams are triggered by some unacceptable repressed wishes often of sexual nature
- thought he could understand ppl by exposing the meaning of latent dreams through interpretation of manifest dreams

manifest dreams: the dreams we experience
latent dreams: versions of our real dreams

Question 22

T o F: dreams are influenced by what we experienced in the wakefulness period prior

Answer 22

T

Question 23

T or F: amount of anxiety experienced prior to dreaming affects the emotional content of dreams

Answer 23

T

Question 24

3 theories about why we dream

Answer 24

Hobsons activation synthesis hypothesis, Revonsuo’s evolutionary theory of dreams and Hobsons protoconsciousness hypothesis

Question 25

explain the activation synthesis hypothesis

Answer 25

- during sleep, many brain system circuits become active and bombard the cerebral cortex with neural signals - information supplied to the cortex during sleep is largely random and the resulting dream is the cortex's efforts to make sense of these random signals

Question 26

Explain Revonuso's evolution theory of dreams

Answer 26

dreams serve as important biological functions which are implicated in the darwinism sense - we dream to better predict and respond to such threats as when we are awake

Question 27

Explain Hobsons protoconsciousness hyopthesis

Answer 27

proposed that dreaming is important during early development when sensory input is limited (especially underdeveloped visual system) and throughout ones life by predicting how events will unfold in real life

Question 28

Major brain areas involved with dreaming

Answer 28

medial prefrontal cortex, medial occipital lobe, temporo parieto junction

Question 29

What is the recuperation theory of sleep

Answer 29

being awake disrupts homeostasis, and sleep restores it by restoring energy levels, clear toxins (beta amyloid plaques) and restore synaptic plasticity

Question 30

What is the adaptation theory of sleep

Answer 30

sleep is not a reaction to the disruptive effects of being awake but the result of an internal 24-hour timing mechanism

Question 31

T or F: sleep disruption effects are worse for executive function and have little effects on cognitive function

Answer 31

T

Question 32

what are microsleeps?

Answer 32

brief periods of sleep where participants eyelids droop for 2-3 secs and are less responsive