Biological Rhythms: Infradian and Ultradian Rhythms Flashcards
What is an untraditional rhythm?
A biological rhythm with a frequency of more than one cycle in 24 hours
What is an infradian rhythm?
A biological rhythm with a frequency of less than one cycle in 24 hours
What are examples of infradian rhythms?
- Menstrual cycle
- Seasonal Affective Disorder (SAD)
What are examples of ultradian rhythms?
Sleep cycle
Describe the menstrual cycle:
- Levels of oestrogen causes ovaries to develop and release an egg
- Progesterone helps the womb lining to thicken, readying the body for pregnancy
- If no pregnancy then egg is absorbed and womb lining comes away hand leaves the body
What did Stern and McClintock (199) do?
- 29 women with irregular periods
- Pheromones were taken at different stages of cycle visual cotton pad
- Pads cleaned with alcohol and rubbed on lips of other participants
What did Stern and McClintock (1989) find?
68% of women experienced changes to cycle which brought them close to their ‘odour donors’
What is Seasonal Affective Disorder (SAD)?
Depressive disorder (low mood/activity) with a seasonal pattern
What is another type of rhythm does SAD come under other than infradian rhythm?
Circannual
What is released during the night which is linked to SAD?
Melatonin
Which gland is melatonin secreted from?
Pineal gland
What stimulus causes the release of melatonin?
The dark
Is the release of melatonin increased or decreased during the winter?
Increased
What knock-on-effect does melatonin have?
Effect secretions of serotonin
What type of rhythm is stages of sleep?
Ultradian