Biopsychology: infradian and ultradian rhythms

Question 1

What is Infradian rhythm

Answer 1

A type of biological rhythm with a frequency of less than one cycle in 24 hours e.g. menstruation and SAD

Question 2

What were Stern and McClintock (1998) findings

Answer 2

68% of women experienced changes tot heir cycle which brought them closer to the ‘odour donor

Question 3

What was the procedure for Stern and McClintock (1998) research

Answer 3

29 women. pheromones were gathered from 9 women at different stages of their cycle via the armpit. They wore pads for at least 8 hours, they were then frozen and treated with alcohol, then rubbed on the upper lip of the other 20 women

Question 4

What is SAD

Answer 4

A type of depression in winter caused by melatonin a which is secreted during sleep whilst it is dark, due to the period of darkness being longer, thought to have an effect on the production of serotonin.

Question 5

What is the Ultradian rhythm

Answer 5

A type of biological rhythm with a frequency of more than one clycle in 24 hours e.g. stages of sleep

Question 6

What are the possible causes of seasonal affective disorder

Answer 6

symptoms triggered in winter months=daylight hours shorter

night=pineal gland secretes melatonin until dawn (light up)
- lack of light=longer secretion=effect serotonin production

Question 7

Describe stages 1 and 2 of the sleep cycle

Answer 7

• light sleep=easily woken
• beginning of sleep, brainwaves slower/rhythmic (alpha waves), then slower (theta waves) as sleep gets deeper

Question 8

Describe stages 3 and 4 of the sleep cycle

Answer 8

delta waves=slower/greater amplitude
- deep sleep/slow wave sleep=difficult to wake someone

Question 9

Describe stage 5 of the sleep cycle

Answer 9

body paralysed
- brain activity speeds=awake brain
- REM=rapid eye movement
- REM activity highly correlated to dream

Question 10

What are the evaluation points of ultradian and infradian rhythms?

Answer 10

evolutionary basis of the menstrual cycle
- methodological limitations in synchronisation studies
- evidence supports the idea of distinct stages in sleep
- animal studies
- practical application to SAD

Question 11

What is the evolutionary basis of the menstrual cycle evaluative point of ultradian and infradian rhythms?

Answer 11

past=advantageous to menstruate together=pregnant together=newborns raised in group=increase survival

Question 12

What is the methodological limitations in synchronisation studies evaluative point of ultradian and infradian rhythms?

Answer 12

confounding variables e.g. stress/diet/exercise not controlled
- patterns in synchronisation may due to chance
- small samples;self report

Question 13

What is the evidence supports idea of distinct stages in sleep evaluative point of ultradian and infradian rhythms?

Answer 13

Dement/Kleitman: 9 adult sleep patterns in lab;EEG;control caffiene/alcohol;REM highly correlated to dreaming;brain activity varied how vivid dreams were
- replicated;small sample size

Question 14

What are the animal studies evaluative point of ultradian and infradian rhythms?

Answer 14

• knowledge of pheromone effect on behaviour derived from animal studies
• evidence for effect in human behaviour speculative/inconclusive
• can’t fully generalise animal study findings

Question 15

What are the practical applications to SAD of ultradian and infradian rhythms?

Answer 15

phototherapy=reset melatonin levels=relieve symptoms in 60% sufferers
- placebo effect 30% ‘sham negative ion generator’=doubt on influence of phototherapy