infradian ryhtyms

• what are Infradian rhythms?

  rhythms that last longer than 24 hours and can be weekly monthly or even annually
• 1. A monthly infradian rhythm is the female menstrual cycle, which is regulated by hormones that promote ovulation or stimulate the uterus for fertilisation. 
  2. Halfway through the cycle is ovulation - oestrogen levels are highest, (lasts for 16-32 hours). 
  3. After the ovulatory phase, progesterone levels increase in preparation for the possible implantation of an embryo in the uterus. 
  4. Normal cycle lasts 28 days, there cqn be variation, so a cycle of 23 days and others cycles up to 36 days.
• seasonal affective disorder 

  • Research has found seasonal variation in mood, 
  • SAD is an infradian rhythm on a yearly cycle. 
  • Psychologists claim The lack of light and longer nights during the winter months results in a longer period of melatonin secretion by the pineal gland which has been linked to the depressive symptoms.
  • Most deaths occurring in january