Biological Rhythms

Question 1

Biological rhythms

Answer 1

Controlled by internal body clocks (endogenous pacemakers) and external cues (exogenous zeitgebers)

Question 2

Circadian rhythms

Answer 2

Biological rhythms, subject to a 24 hour cycle

Question 3

Two examples of circadian rhythms

Answer 3

Sleep/Wake cycle
Core body temperature

Question 4

The sleep/wake cycle

Answer 4

Governed by daylight and by biological clock (SCN), gets light information from the eyes

Question 5

Siffre’s cave study

Answer 5

His free running rhythm extended slightly to 25 hours when deprived of daylight

Question 6

Other research on circadian rhythms
(Support for exogenous Zeitgebers)

Answer 6

Support for exogenous zeitgebers entraining internal clock (Aschoff and Weavers, bunker, natural rhythm longer)

Question 7

Other research on circadian rhythms
(Support for endogenous cues)

Answer 7

Support for endogenous cues if difference too big (Folkard cave with 22 hour day)

Question 8

Biological rhythms evaluation points- Shift work

Answer 8

STRENGTH

Reduced concentration at 6 am, more accidents (Boivin) Heart disease three times more likely (Knutsson)

Question 9

Biological rhythms evaluation points- Counter point to shift work

Answer 9

LIMITATION

Studies are correlational, effects may be due to disruptive social routines (Solomon)

Question 10

Biological rhythms evaluation points- Medical treatment

Answer 10

STRENGTH

Timing of drugs (Chronotherapeutics), aspirin more effective at night for a heart attack (Bonten)

Question 11

Biological rhythms evaluation points- Individual differences

Answer 11

LIMITATION

Cycle length is vary (13 to 65 hours, Czeisler), ‘larks’ and ‘owls’ (Duffy), generalisation may be meaningless

Question 12

Infradian rhythms

Answer 12

Bodily rhythm that takes more than 24 hours to complete

Question 13

What are the two examples of Infradian rhythms

Answer 13

• Menstrual cycle
• Seasonal Affective Disorder

Question 14

The menstrual cycle

Answer 14

Oestrogen regulate ovulation, progesterone readies the body for pregnancy (Endogenous factors)

Question 15

Synchronising the menstrual cycle

Answer 15

Menstrual cycle is synchronised through pheromones, exogenous factor
(Stern and McClintock)

Question 16

Seasonal affective disorder

Answer 16

Form of depression triggered in the winter months and regulated by melatonin, a circannual rhythm

Question 17

Infradian rhythms evolution points- Evolutionary basis

Answer 17

STRENGTH

Synchronisation may have an adaptive function, leads to shared care for babies

Question 18

Infradian rhythms evolution points- Methodological limitations

Answer 18

LIMITATION

Mini confounding variables not controlled to synchronisation maker by chance (Trevathan)

Question 19

Ultradian rhythms

Answer 19

Bodily rhythm that takes less than 24 hours to complete

Question 20

Stage 1 and 2 of the ultradian rhythms

Answer 20

Alpha waves and sleep spindles

Question 21

Stage 3 and 4 of ultradian rhythms

Answer 21

Deep sleep in Delta waves

Question 22

Stage 5 of ultradian rhythms

Answer 22

R.E.M. (Rapid Eye Movement) sleep theta waves

Question 23

Ultradian rhythms evolution points- Improved understanding

Answer 23

STRENGTH

SWS reduces the age, explains issues in old age e.g. reduced alertness (Van Cauter)

Question 24

Ultradian rhythms evolution points- Individual differences

Answer 24

LIMITATION

Differences found in duration of each leap stage, particularly stages 3 and 4
(Tucker)