infradian and ultradian rhythms - biopsychology

Question 1

what are infradian rhythms

Answer 1

biological rhythm
occurs less than one cycle in 24 hours

Question 2

example of infradian rhythms

Answer 2

menstruation and seasonal affective disorder (SAD).

Question 3

how dose the menstral cycle work

Answer 3

Rising levels of oestrogen cause ovary to release an egg

progesterone helps the womb lining to thicken, readying the body for pregnancy.

If pregnancy does not occur, the egg is absorbed into the body and the womb lining comes away and leaves the body

Question 4

who studied women’s menstral cycles

Answer 4

Stern and McClintock (1998)

29 women’s irregular periods

Question 5

what was stern and mcclintocks procedure

Answer 5

Pheromones taken via cotton pad under armpit

pads were cleaned with alcohol and later rubbed on the upper lips of the other participants.

Question 6

what were stern and mcclintocks findings

Answer 6

68% of women experienced changes to their cycle
closer to the cycle of their ‘odour donor’.

demonstrates how menstrual cycles may synchronise as a result of the influence of pheromones.

Question 7

what triggers seasonal depressive disorder

Answer 7

triggered during the winter months when the number of daylight hours becomes shorter.

Question 8

what type of infradian rhythms is Seasonal depressive disorder

Answer 8

a circannual rhythm - subject to a yearly cycle.

Question 9

what causes SAD

Answer 9

melatonin - during night pineal gland secretes melatonin until there is an increase in light.

During winter - lack of light in the morning means secretion goes on for longer.

effects the production of serotonin in the brain –serotonin linked to depressive symptoms.

Question 10

what are ultradian rhythms

Answer 10

biological rhythm with a frequency of more than one cycle in 24 hours

Question 11

example of ultradian rhythms

Answer 11

the stages of sleep (sleep cycle)

Question 12

when do the stages of sleep occur

Answer 12

90 minute periods

five stages - characterised by a different level of brainwave activity

Question 13

what are stage 1 and 2 of sleep cycle

Answer 13

light sleep - easily woken
brain waves - high frequency + short amplitude
stage 1 and 2 = alpha waves
stage 2 = occasional random changes in pattern called sleep spindles.

Question 14

what Are stage 3 and 4 of sleep cycle

Answer 14

deep sleep
waves - delta
low frequency and high amplitude

Question 15

what is stage 5 of sleep cycle

Answer 15

REM - rapid eye movement sleep
body is paralysed yet brain activity resembles awake brain
waves - threta
dream often occur at REM

Question 16

One strength is research on the menstrual cycle

Answer 16

its evolutionary basis.

advantageous for females to menstruate together and become pregnant at the same time.

In a social group, this would allow babies who had lost their mothers to have access to breast milk, thereby improving their chances of survival.

Question 17

one strength of SAD reaserch

Answer 17

real world applicate