Biological Rhythms: Infradian And Ultradian Rhythms Flashcards
Outline- infradian rhythm- menstrual cycle
- a cycle that completes every 28 days as a result of changes in hormone levels which regulate ovulation. Rise in the level of of oestrogen which stimulates the release of an eggs and the womb lining being released.
Outline- McClintock (1998)
-29 women with irregular periods
- samples of pheromones were gathered from 9 of the women at different stages of their cycle from the arm pit.
- the pheromones were rubbed on to the upper lip of the rest of the women.
Found- 68% of women experienced changes to their cycle which brought them closer to the cycle of their ‘odour donor’
Outline- Seasonal Affective Disorder (SAD)
- depression that is triggered in the winter months, when the hours of daylight are shorter. It has a circannual rhythm that occurs once every year.
- found melotonin is implicated in the cause of SAD. during winter the lack of light in the morning means the secretion of melotonin lasts for longer. And then this affects serotonin which is a chemical linked to depression.
Outline- stages of sleep
Stages 1 and 2- light sleep when easily woken. Brainwave patterns become slower slower (alpha waves to theta waves)
Stages 3 and 4- delta waves which are slower still, very deep sleep.
Stages 5 and REM- body is paralysed yet brain activity speeds up. REM stands for, rapid eye movement, which is when we dream.
Evaluation- dement and kleitman
- monitored sleep patterns of nine adult participants in a sleep lab.
- brainwave activity was recorded on an EEG and the researchers controlled for the effects of caffeine and alcohol. REM Activity during sleep was highly correlated with the experience of dreaming, brain activity varied according to how vivid dreams were, and participants woken during REM had vivid memory of their dream.
- suggests REM sleep is an important component of the ultradian cycle
Evaluation- Trevathan et al
-failed to find any evidence of menstrual synchrony in all female samples.
