Infradian And Ultradian Rhythms Flashcards
Define ultradian rhythm
Lasts fewer than 24 hrs such as cycle of sleep stages that occur through the night
Describe the sleep stages
- cycle alternates between REM and NREM “
1. Stages 1 and 2 is light sleep- brain wave patterns become slower and more rhythmic starting with alpha waves progress to theta waves.
2.stages 3 and 4- deep sleep- associated with delta waves- brain generates slow delta waves, rhythmic breathing, limited muscle activity
Stages 1,2,3,4 is NREM sleep
3. Stage 5 is REM sleep - body is paralysed to stop people acting out the dream- brain activity represents that of an awake person- rapid eye movements,heart rate increases, breathing is rapid
Define infradian rhythm
Type of biological rhythm that lasts longer then 24 hrs and can be weekly,monthly,annually
Monthly infradian rhythm is the menstrual cycle
Describe
Regulated by hormones that promote ovulation or stimulate the uterus for fertilisation
-ovulation occurs halfway through the cycle when oestrogen levels are at its highest- lasts 16-24 hrs
-after progesterone levels,a increase for possible implantation of an embryo in the uterus
-menstrual cycle usually lasts 28 days but some women have it for 23 or 36
AO3 infradian rhythms
—menstural synchronisation is not presented in all females
-no evidence of all female pps of menstrual synchronisation- extraneous variables ie smoking,alcohol,physical activity
+research support by McClintock et al
-mesnstural cycle synchronisation amongst 29 women-9 women has pad underarm pit and then rubbed on to lip to the other 20- found women short ended or extended menstrual cycle to match donor
AO3 ultradian rhythm
— lacks ecological validity
- pps attached to monitors- subjected to levels of control- may sleep in a way that don’t reflect ordinary sleep cycle
— individual differences
- Tucker et al found found differences between pps in terms of duration in each stage- in particular stage 3 and 4 just before REM sleep
