biological rhythms

Question 1

what are ultradian rhythms?

Answer 1

last less than 24 hours, but occur more than once every 24 hours - e.g. stages of sleep

Question 2

what happens in stage 1 of sleep + brain waves?

Answer 2

non-rem sleep –> changeover from wakefulness to sleep, can easily be woken
- alpha waves (high frequency and short wavelength)

Question 3

what happens in stage 2 of sleep + brain waves?

Answer 3

non-rem sleep –> light sleep before you enter deeper sleep
- brief bursts of SLEEP SPINDLES (electrical activity)
- alpha waves

Question 4

what are sleep spindles and what are they useful for?

Answer 4

brief bursts of electrical activity - help with consolidation of procedural and declarative memory

Question 5

stages 3 and 4 of sleep + brain waves?

Answer 5

non-rem sleep –> period of deep sleep
- heartbeat and breathing rate levels are at their lowest
- muscles are relaxed - difficult to wake you
- delta waves (even slower)

Question 6

what is REM sleep? (stage 5)

Answer 6

• dreaming occurs in REM sleep
• occurs 90 minutes after you fall asleep
• theta waves

Question 7

supporting study - Cauter et al (2000)

Answer 7

sleep patterns of men change with age, during slow wave sleep and REM sleep due to hormonal shifts. Less of the growth hormone is produced in REM sleep as you get older. Cortisol levels increase with age.

Question 8

supporting study - Tucker et al (2007)

Answer 8

• conducted sleep studies in the lab, extraneous variables controlled
• there is a variation in sleep patterns between different subjects
• duration of stages varies - may be genetically programmed
• due to controlled setting (lab) - ppts may not sleep normally due to unfamiliar setting, may not be ecologically valid

Question 9

circadian rhythms

Answer 9

occur once every 24 hours e.g. sleep wake cycle

Question 10

endogenous pacemakers

Answer 10

the body’s internal biological clock

Question 11

exogenous zeitgebers

Answer 11

changes in the environment