biological rhythms : ultradian rhythms

Question 1

What is an ultradian rhythm?

Answer 1

a type of biological rhythm that takes less than 24 hours to complete

Question 2

What is an example of the ultradian rhythms?

Answer 2

sleep cycle

Question 3

What happens during stage 1 & 2 of the sleep cycle?

Answer 3

• light sleep where the person is easily woken
• brainwave patterns become slower & more rhythmic (alpha waves)
• patterns become even slower as sleep gets deeper (theta waves)

Question 4

What happens during stage 3 & 4 of the sleep cycle?

Answer 4

• delta wave which are even slower and have greater amplitude
• deep sleep or slow wave sleep
• difficult to rouse a person

Question 5

What happens during stage 5 of the sleep cycle?

Answer 5

• the body is paralysed
• brain activity speeds up to the extent it resembles the awake brain
• Rapid Eye Movement (REM) reflect the fast , jerky activity of the eyes at this point
• highly correlated with the experience of dreaming

Question 6

How is improved understanding a strength of ultradian rhythms?

Answer 6

• research into ultradian rhythms has led to improved understanding of age related changed in sleep
• sleep scientists observed that sleep stages reduce with age (sleep/wake cycle changes)
  
  • this as growth hormones are mostly produced during sleep and therefore it is reduced in old people
• may result in various issues in old age as relaxation and medication may be used to induce a deeper sleep

Question 7

How is the sleep lab a strength of ultradian rhythms?

Answer 7

sleep labs use controlled settings and research can exclude extraneous factors ( such as noise , temperature)

Question 8

How is the sleep lab a weakness of ultradian rhythms?

Answer 8

Lab studies involve ppts being attached to artificial machinery which can lead to ppts to sleep in a way that doesn’t represent normal sleep. This means that findings from the study may lack generalisability .

Question 9

How are individual differences a weakness of ultradian rhythms?

Answer 9

• there’s a significant variation between people
• Tucker = found large difference between ppts in terms of duration of each sleep stage ( especially stage 3 & 4)
  • these differences are biologically determined which makes it difficult to describe normal sleep in a meaningful way