Using the Laptops…Follow the instructions on page 6 of your workbook

Biological Rhythms

A2 Psychology – PSYA3

Introduction to Biological Rhythms and Sleep

Connect…What kind of rhythms or

cycles do we experience

in our lives?????

Objectives…By the end of this lesson you should be able to…

Understand the exam requirements of this topic

Distinguish between different types of biological rhythms

What is a biological rhythm?

The human body has rhythms and cycles that occur regularly e.g: Menstrual cycle Sleep-wake cycle Body temperature etc.

We don’t always know why our cycles occur in the way that they do: Changes in environment? Natural body clock?

Biological

Rhythms

Ultradian Rhythms•Take less than 24 hours•E.g. the Sleep Stages cycle

Circadian Rhythms•Take just 24 hours•E.g. the Sleep –wake cycle

Infradian Rhythms•Take longer than 24 hours•E.g. the menstrual cycle

Ultradian rhythms

Research by….BergerDement & Kleitman

External control:Modification byZeitgebers

Endogenous control:Pacemaker (SCN)

Research by:Fulton and Bailey (tumors)

Jouvet (rats)

Inouye and Kawamoura (rats)

Ralph et al (mutant hamsters)

Research by:Michel Siffre (cave)

Aschoff & Wever (bunker)

Circadian rhythms

http://www.youtube.com/watch?v=jFfAbMbrZrA

Menstrual cycle:

Endogenous control

Pacemaker = pituitary gland

Regular production of hormones (FSH and LH) by the pituitary gland over a 28 day period, causes regular thickening and shedding of the uterus wall, together with ovulation (egg maturation and release)

Modification by external Zeitgebers1.Russell et al. – donorpheromones on lips of female test participants

Infradian Rhythms

Modification by external Zeitgebers2.McClintick et al. – the effect of male pheromones

Complete the activities on pages 7 and 8