Biological Rhythms: Infradian and Ultradian Flashcards
What are ultradian rhythms?
Rhythms subject to less than 24 hour cycles.
What do ultradian rhythms regulate?
- Sleep stages.
- Blinking.
- Basic rest activity cycle.
What are infradian rhythms?
Rhythms subject to more than 24 hour cycles.
What do infradian rhythms regulate?
- Menstrual cycle.
- Seasonal affective disorder.
What are 2 examples of infradian rhythms?
- Seasonal Affective Disorder (SAD)
- Menstrual cycle
Outline Seasonal affective disorder.
-Occurs in winter due to less light.
-Less light = less serotonin produced.
-More melatonin due to less light.
-Melatonin inhibits serotonin (mood transmitter).
Outline the menstrual cycle.
-Production of eggs.
-Uterus lining sheds.
-FSH, LH, progesterone and oestrogen.
-Average cycle between 23-36 days.
Give 2 strengths of infradian rhythms.
- SAD lamps can be used to treat disorder.
60% saw improvement.
Lamps are cheap - no therapy needed.
Therefore, cost effective + less strain on economy. - Affect relationship behaviour.
Women may no longer be attracted to their partner when they come off pill.
Shows women need to be aware of consequences.
Therefore, real life application.
What are 3 examples of ultradian rhythms?
- Sleep wake cycle.
- Thermoregulation.
- Blood circulation.
Outline the sleep cycle.
90 minute cycles - 5 full cycles.
Move through alpha, theta, delta, and theta waves.
What is meant by sleep spindle?
Indicates you have reached stage 2 and are fully asleep.
What did Kleitman suggest with ultradian rhythms?
90 minute cycles exist when awake.
Basic rest activity cycle: alertness is followed by physiological fatigue.
Physiological fatigue results From hunger, thirst etc.
Give one strength of ultradian rhythms.
Research support.
Dement + Kleitman: REM activity during sleep highly correlated with dreaming.
Shows idea of sleep stages has credibility as REM influences certain stage.
Therefore, distinct sleep stages.
