Biopsysch: infradian and ultradian rhythms

Question 1

Ultradian: five stage sleep cycle 90 mins

Answer 1

stage 1 & 2 = shallow sleep where alpha and beta waves are produced
3 & 4 = deeper, delta wave production
5 = REM sleep where dreaming occurs

Question 2

Infradian: menstrual cycle

Answer 2

oestrogen regulates ovulation and fertility - endogenous

Stern & McClintock found evidence that they can synchronise due to hormones (exogenous).

Question 3

Stern & McClintock

Answer 3

gathered pheromones from 9 women at various stages of their monthly cycle, and rubbed them on the upper lip of 20 others. 68% experienced some adjustments in their cycle

Question 4

Another example

Answer 4

(SAD) due to the pineal gland, being disrupted by the darker mornings and shorter days of winter. having a knock on effect on serotonin

Question 5

Evaluation strength: Dement & Kleitman

Answer 5

monitored sleep patterns of nine participants using an EEG. found a clear correlation between REM activity and the experiences of dreaming

Question 6

Strength: methodological issues

Answer 6

confounding variables that effect a women’s cycle reduces validity and reliability of research

Question 7

strength:

Answer 7

treatments of SAD. patient may use a light box that produces intense light in the mornings and evening to reset melatonin levels

Question 8

Weakness:

Answer 8

animal research - sea urchins have been found to release pheromone into water to prompt fertilisation