infradian

    Cards (37)

    • What is an infradian rhythm?
      A cyclical change longer than a day
    • How is an infradian rhythm characterized?
      By one peak and one trough
    • What is an example of an infradian rhythm in humans?
      The female menstrual cycle
    • What are examples of circannual rhythms in animals?
      Migration and hibernation
    • How long does the menstrual cycle typically last?
      28 days
    • What controls the menstrual cycle?
      The body's endogenous pacemakers
    • What can influence a female's menstrual cycle?
      Exogenous zeitgebers like pheromones
    • What does FSH stand for?
      Follicle stimulating hormone
    • What hormone is released during the luteal phase?
      Progesterone
    • What are the phases of the menstrual cycle?
      1. Menstrual phase
      2. Follicular phase
      3. Ovulation phase
      4. Luteal phase
    • What marks the beginning of the menstrual phase?
      The first day of the period
    • Why does the menstrual phase occur?
      Because fertilization has not occurred
    • How long does the menstrual phase typically last?
      3 to 7 days
    • What initiates the follicular phase?
      Release of FSH from the pituitary gland
    • What happens to the follicles during the follicular phase?
      Only the healthiest egg matures
    • What does the maturing follicle cause to happen?
      A surge in estrogen levels
    • What is ovulation?
      Release of a mature egg from the ovary
    • When does ovulation typically occur in a 28-day cycle?
      Around day 14
    • What happens to the egg after ovulation?
      It travels down the fallopian tube
    • What occurs during the luteal phase?
      The corpus luteum releases hormones
    • What happens if fertilization does not occur after ovulation?
      The female gets her period again
    • What were the findings of McClintock's study on menstrual synchrony?
      • 29 women studied over 10 years
      • 68% of recipients responded to pheromones
      • Cycles shortened by 1.7 days in follicular phase
      • Cycles lengthened by 1.4 days in ovulatory phase
    • What did Russel et al confirm about pheromones?
      Pheromones can entrain menstrual cycles
    • What issue did Trevathan et al raise about McClintock's findings?
      They failed to replicate the findings
    • What confounding variables might affect menstrual synchrony?
      Stress, diet, exercise, health conditions
    • What did Reinberg's study suggest about light levels?
      Light levels can influence cycle periods
    • What was the average menstrual cycle length reported by Reinberg?
      25.7 days
    • How does light affect serotonin levels?
      Low light decreases serotonin levels
    • What is Seasonal Affective Disorder (SAD)?
      • Extreme form of winter depression
      • Related to lack of bright light
      • Influences melatonin and serotonin levels
    • What treatment has been shown to reduce SAD symptoms?
      Light therapy
    • What did Terman find about SAD prevalence?
      SAD is more common in northern states
    • What was the conclusion of Terman et al's study on light exposure?
      Bright light may reset the body clock
    • What are the potential mechanisms of light therapy for SAD?
      • Lowers melatonin levels
      • May directly affect mood
      • May influence serotonin levels
    • What type of drugs are used to treat depression related to SAD?
      Prozac and MAOIs
    • What percentage of the bright light group showed improvement in Terman's study?
      60%
    • What percentage of the placebo group showed improvement in Terman's study?
      5%
    • What is a potential genetic component in SAD?
      There may be a genetic predisposition
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