task 6

Question 1

The three standard psychophysiological bases for defining sleep in stages

Answer 1

1. electrocehalogram (EEG)
2. electrooculogam (EOG)
3. electromyogram (EMG)

Question 2

first-night phenomenon

Answer 2

the disturbance of seep observed during the first night in a sleep laboratory.

Question 3

there are…. stages if sleep

Answer 3

4

Question 4

just before sleep (as seen on a EEG)

Answer 4

• alpha waves : waxing and waning bursts of 8-13 Gz

Question 5

stage 1

Answer 5

• low voltage, high frequency (slower than that of alert wakefulness)
• also called REM sleep
• loss of cire-muscle tone
• ceberal activity (bloodflow, neuron firing) increases till waking levels in many brainstructures
• general increase in the variability of the autonomic nervous system system (respiration, blood pressure)
• penile erection in males

Question 6

stages 2

Answer 6

• gradual increase in voltage and decrease in frequency compared to stage 1
• K complex: a large negative wave (upwards), followed by a single large positive wave (downwards)
• sleep spindle: waxing and waning outbursts of 12-14 Hz waves
• NREM sleep (non-rem sleep)

Question 7

stage 3

Answer 7

• gradual increase in voltage and decrease in frequency compared to stage 1 and 2
• occasional presence of delta waves

Question 8

delta waves

Answer 8

the largest and slowest EEG waves, with a frequency of 1-2 Hz

Question 9

stage 4

Answer 9

• gradual increase in voltage and decrease in frequency compared to the other stages
• a predominance of delta waves

Question 10

initial stage 1 EEG

Answer 10

• first period of stage 1 EEG

- not marked striking EOG or EMG changes

Question 11

emergent stage 1 EEG

Answer 11

• subsequent periods of stage 1 sleep EEG
• REMs
• loss of tone in the muscle of the body core

Question 12

REM sleep

Answer 12

rapid eye movement

Question 13

slow-wave sleep (SWS)

Answer 13

sleep 3 and 4 together ( =because of delta waves)

Question 14

Freud on dreams

Answer 14

manifest dreams (sleep dreams) are merely disguised versions of our latent dreams (real dreams)

Question 15

activation-synthesis theory

Answer 15

the information supplied by the cortex during REM sleep is largely random and that the resulting dream is the cortex’s effort to make sense of these random signals.

Question 16

recuperation theories of sleep

Answer 16

being awake disrupts the homeostasis of the body in some way and sleep is required to restore it

Question 17

adaptation theories of sleep

Answer 17

• sleep is the result of an internal 24-hour timing mechanism.
• To conserve energy resources and to be less susceptible to predation in the dark
• sleep is a behaviour we are highly motivated to engage in, but not necessary to stay healthy

Question 18

the effects of sleep deprivation are often difficult to study because they are often cofounded by

Answer 18

stress

Question 19

sleep deprivation leads to (3)

Answer 19

1. increase in sleepiness
2. worse performance on written tests of mood
3. worse performance on tests of vigilance (computer screen responding)

Question 20

sleep deprivation impacts which cognitive function

Answer 20

worse performance on tests of executive function

Question 21

executive function

Answer 21

cognitive abilities that appear to depend on the prefrontal cortex. For example, innovative thinking, lateral thinking, assimilating new information to update plans and strategies.

Question 22

physiological consequences of sleep deprivation

Answer 22

• reduced body temperature
• increased blood pressure
• decreases in some aspects of immune function
• hormonal changes
• metabolic changes

Question 23

microsleeps

Answer 23

brief periods of sleep (2-3 seconds long) during which the eyelids drop and you become less responsive to external stimuli while your still standing or sitting

Question 24

the carousel apparatus is used to

Answer 24

deprive an experimental rat of leep

Question 25

REM sleep deprivation has two effects

Answer 25

1. following REM sleep deprivation, someone display a REM rebound 2. with each successive night of REM sleep deprivation, there is a greater tendency for participants to initiate REM sequences.

Question 26

REM rebound

Answer 26

people will have more than usual amount of RE sleep for the first two nights after the REM sleep deprivation

Question 27

mnemonic function

Answer 27

pertaining to memory

Question 28

according to the default theory of REM sleep

Answer 28

- it is difficult to stay continuously in NREM sleep, so the brain periodically switches to one of the other two states. - REM sleep and wakefulness are similar states

Question 29

antidepressants reduce

Answer 29

REM sleep

Question 30

sleep deprivation causes sleepers to become more efficient because

Answer 30

- sleep deprived have a higher proportion of slow-wave sleep, which is the main restorative function

Question 31

circadian rhythms

Answer 31

rhythms lasting about a day

Question 32

nocturnal animals

Answer 32

animals that sleep during the day and stay awake at night

Question 33

zeitgebers

Answer 33

environmental cues, such as light-dark cycle, that can control the timing of the circadian rhythms

Question 34

circadian rhythms are

Answer 34

- freerunning rhythms | - freerunning period

Question 35

the biological clock habitually runs

Answer 35

-slow unless it is entrained by timerelated cues in the environment (25 hours instead of 24)

Question 36

internal desynchronization

Answer 36

when subjects are housed in constant laboratory environments, their sleep-wake cycle and body temperature cycles sometimes break away from one another

Question 37

jet lag occurs when

Answer 37

the zeitgebers that control the phases of various circadian rhythms are accelerated during west-bound flights (phase advances) or decelerated during east-bound flights ( phase delays)

Question 38

what happens in shift work

Answer 38

the zeitgebers stay the same, but workers are forced to adjust their natural sleep-wake cyclus in order to meet the demands of their work schedule.

Question 39

2 ways of reducing jet lag

Answer 39

1. gradually shifting someone sleep-wake cycle in the days prior to the flight 2. administering treatments after the flight that promote the required shift in the circadian rhythm

Question 40

circadian clock

Answer 40

internal timing mechanism that by using physiological systems regulate sleep

Question 41

suprachiasmatic nuclei

Answer 41

- SCN - located in the medial hypothalamus - disrupts circadian cycles therefore contains a circadian timing mechanism

Question 42

There are minor circadian clocks in mammals for example

Answer 42

cells from other parts of the body display free-running circadian cycles of activity when maintained in tissue culture