Rhythms

Question 1

What is the circadian rhythm

Answer 1

24 hour long
Sleep wake cycle
Body temp
Hormone production

Question 2

How is core body temperature regulated in sleep

Answer 2

Body temp rises at our last few hours of sleep, creating alertness in the morning
Small drop in temp in the afternoon creates sleepiness

Question 3

How does circadian rhythm control hormones

Answer 3

Produces melatonin
Highest during darkness
Encourages sleepiness

Question 4

What case study is used for circadian rhythms

Answer 4

Michel strife

Question 5

Who is Micheal siffre

Answer 5

Cave expert who investigated his sleep/ wake cycle for 6 months with artificial light
Found there was no effect showing internal body clock

Question 6

Evaluate circadian rhythm

Answer 6

+ practical app to shift work- knutson- shift workers 3 times more likely to get heart disease- economic implications
+ practical app to drug treatments- treatments for cancer/ epilepsy more effective at certain times- real life medical benefits
- small samples- siffre- at 60 biological clock slower
- Individual differences- czeisler found sleep wake cycles can vary 13 to 65 hours- also age differences- not representative

Question 7

What is a endogenous pacemaker

Answer 7

Internal body clock that regulate biological rhythms

Question 8

What are exogenous zeitgebers

Answer 8

Environmental cues that help regulate our biological clock

Question 9

What is responsible for our endogenous pacemaker

Answer 9

Suprachiasmatic nucleus and pineal gland

Question 10

What is the SCN, where is it located ?

Answer 10

Located in hypothalamus
Master clock
Sends signals to peripheral clocks that maintain sleep/ wake cycle

Question 11

How does the SCN send signals to peripheral clocks and maintain sleep/ wake cycle

Answer 11

SCN recieve info via optic nerve on light
Morning light will speed up biological clock
At the of the day SCN sends signals to pineal gland to secrete melatonin

Question 12

What are two examples of exogenous zeitgebers

Answer 12

Light and social cues

Question 13

How does light work at regulating our biological clock

Answer 13

Receptors in SCN sensitive to light. They use this to reset our biological clock
Melanopsin in the eye gauges brightness to reset biological clock

Question 14

Example of social cues

Answer 14

Mealtime

Question 15

What is an ultradium rhythm

Answer 15

Less than 24hours
Eg- sleep cycle
BRAC- basic rest activity cycle

Question 16

What are infradium rhythms

Answer 16

Longer than 24 hours
Menstrual cycle
Seasonal affective disorder

Question 17

What are the stages of the sleep cycle

Answer 17

Stage 1&2: light sleep- alpha to beta waves
Stages 3&4 : difficult to rouse- deep sleep- delta waves
Stage 5: REM sleep- body paralysed but brain speeds up

Question 18

What is BRAC

Answer 18

Focus’s period for 90 mins

Question 19

Evaluate ultradium and infradium rhythms

Answer 19

+ highest scientific validity- brain scans/ hormone samples- lab control- high scientific validity
- research- Ericson- violinist practice for 90 mins then nap- BRAC
+ practical app- menstrual cycle= contraceptives- economic implications- unwanted pregnancies
- individual differences- Tucker- 11 night experiment found different sleep stages- not generalisable