Biological Rhythms (Infradian and Ultradian Rhythms) Flashcards
what is an infradian rhythm?
a type of bio rhythm which has a frequency of less than one cycle in 24 hours e.g. menstruation or SAD
what is the female menstruation cycle governed by?
monthly changes in hormone levels which regulate ovulation
what does the menstrual cycle refer to?
time between first day of period, when womb lining sheds to the day before her next period
how long does a typical cycle last?
28 days but 24-35 is considered normal
the rising level of what hormone causes the ovary to develop an egg and release it?
oestrogen
what hormone is present after ovulation? (when egg gets released)
progesterone
what does the hormone progesterone do?
helps the womb lining grow thicker, readying the body for pregnancy
what happens if pregnancy doesn’t occur?
egg is absorbed into the body, the womb lining comes away and leaves the body (the menstrual flow)
who conducted research to show menstrual cycle can be influenced by exogenous factors?
Stern and McClintock
what did Stern and McClintock demonstrate?
how menstrual cycles synchronise as result of inf of female pheromones
who were McClintock’s sample?
29 women with irregular periods
what did McClintock do?
get samples of pheromones from 9 women at diff stages of mens w/ cotton pas
how long were pads worn on armpits?
8 hrs to make sure pheromones picked up
what happened to cotton pads after collection?
treated with alcohol, frozen and rubbedon upper lip of other ppts
what happened on day 1 and day 2 and so on in Stern and McClintock’s exp?
day 1 - pads from start of mens applied to 20 ppts
day 2 - all ppts given pad and so on
what were the findings of Stern and McClintock’s exp?
68% of ppts exp changes to cycle, bringing them closer to cycle of odour donor
what is SAD?
seasonal affective disorder, diagnosed as mental disorder in DSM-5
why is SAD an infradian rhythm?
symptoms such as low mood and interest triggered by winter months when number of daylight hrs are shorter
