Biopsychology: biological rhythms -circadian rhythms

Question 1

what is a biological rhythm?

Answer 1

.a periodic activity of the body that are governed by internal biological clocks (endogenous pacemakers) and external changes (exogenous zeitgebers)

Question 2

what is a circadian rhythm?

Answer 2

.a daily rhythm (lasts about 24 hours)

Question 3

what is an example of a circadian rhythm?

Answer 3

.sleep-wake cycle

Question 4

what is the sleep-wake cycle?

Answer 4

.one period of wakefulness and one period of sleep
.the fact we feel sleepy during the night and alert during the day shows the effect of daylight (an exogenous zeitgeber) on our biological rhythms

Question 5

what are some examples of factors that can influence the sleep-wake cycle?

Answer 5

.light
.temperature
.social cues

Question 6

what is free-running

Answer 6

.a biological clock that’s left to its own devices

Question 7

what gland is associated with feeling sleepy during the sleep-wake cycle?

Answer 7

.pineal gland

Question 8

what hormone is secreted by the pineal gland which makes you feel sleepy during the sleep-wake cycle?

Answer 8

.melatonin

Question 9

what does melatonin do?

Answer 9

.induces sleep

Question 10

what hormone makes us feel alert during the sleep-wake cycle?

Answer 10

.cortisol

Question 11

who conducted the main study in support of the
sleep-wake cycle?

Answer 11

.michel siffre

Question 12

what type of study did michel siffre do?

Answer 12

.longitudinal study

Question 13

what did michel siffre do?

Answer 13

.stayed in a cave where he was deprived of exposure to natural light and sound
.took his own vitals everyday and performed skill tests

Question 15

what were the findings of Michel siffre’s study?

Answer 15

.found his body took a 25 hour day instead of 24 hour day

Question 16

what does this study support the idea of?

Answer 16

.supports the idea that our biological clocks are reset by external factors (exogenous zeitgebers)

Question 17

how does this study supports the idea that our biological clock is reset by exogenous zeitgebers

Answer 17

.because his body took to a 25 hour day not a 24 hour

Question 18

what were some problems with Michel siffre’s study?

Answer 18

.case study (small sample of 1 odd person)
.in an image of siffre, he is visible meaning they brought artificial light into the cave and a study showed that artificial light can effect the body clock so he’s not completely free running

Question 19

who conducted the study that proved artificial light can effect the body clock?

Answer 19

.czeisler et al

Question 20

what did czeisler et al do?

Answer 20

.he could alter circadian rhythms from 22 hours to 28 hours just by using dim artificial light

Question 21

what is a positive to the idea of circadian rhythms?

Answer 21

.real life application to drug treatments:
-drugs taken at certain times in the day can be more effective in line with other biological rhythms eg: aspirin at night to prevent early morning heart attacks