Biopsychology 7/15

Question 1

The sleep/wake cycle

Answer 1

The fact that we feel drowsy when it’s night-time and alert during the day demonstrates the affect of daylight - an important exogenous zeitgber - on our sleep/wake cycle.

Question 2

Exogenous zeitgebers

Answer 2

External cues in the environment that entrain our endogenous rhythms.

Question 3

Endogenous pacemakers

Answer 3

Internal body clocks that regulate many of our biological rhythms.

Question 4

Seasonal affective disorder - SAD

Answer 4

Depression associated with seasonal changes, usually the onset of winter and decreased darkness.

Question 5

Stages of sleep

Answer 5

90-minute cycles during sleep brain, sleep escalator from stage 1 to 5 and REM. Brain wave activity changes.

Question 6

What happens in stage 1 of sleep?

Answer 6

Light sleep; person can be easily woken. Theta waves in stage 1; person in light sleep and can easily be woken

Question 7

What happens in stage 2 of sleep?

Answer 7

Sleep spindles, theta waves and mixed EEG activity. Light sleep where person can be easily woken.

Question 8

What waves are present in stage 3 and 4 of sleep?

Answer 8

Involves delta waves that are slower and greater amplitude than earlier wave patterns. This is deep sleep/slow wave sleep and it’s difficult to rouse somebody at this point.