Psychology: Biological Rhythms
· Circadian Rhythm: A biological rhythm that takes place over 24 hours, such as sleep/wake cycle.
· Infidelity Rhythm: Rhythm that last more than one day and a cycle that occurs less often, for example menstrual cycle 28 days.
· Ultradian Rhythm: Rhythm cycle that occurs more than once in 24 hours, for example sleep stages – 90 minutes cycle.
Control of Circadian Rhythm:
· Endogenous Pacemaker: Internal control mechanisms, i.e. Suprachiasmatic nucleus and pineal gland.
· Exogenous Zeitgebers: Extent control mechanisms, i.e. light.
Process of melatonin release:
- Light enters the eye even when shut.
- Information sent via neural pathways to SCN.
- SCN located in hypothalamus.
- Information sent via neural pathways to Pineal gland.
- Pineal gland is located deep within the Brain.
- Low light information from SCN triggers pineal gland…