Circadian rhythm

What is a circadian rhythm and what is an example

Biological process that takes approximately 24h

Endogenous pace maker

Internal body clock

Exogenous zietgeber

Environmental cue that helps regulate the bodily clock

Describe the sleep wake cycle

7-wake up

11-most alert

2-dip in alertness due to lunch

6-max temp

11-sleep

2-deepest sleep

4:30-min temp

Supercharesmatic nuclei

Endogenous pacemaker

Master clock in hypothalamus sensitive to light - pituitary gland -melatonin

What did Siffer do

In a cave for 6month no exogenous zeitgeber sleep wak cycle only went to 25h

Limitation

Individual differences-czeister et al-sleep wake cycle can vary between 13-65h

Strength

Understand consequences of desynchronisation-shift workers-bovin et al-3x more likely of heart disease

Improved medical treatment-chronotheraputics-can time the medication to kick in at peak time due to body changing throughout the day