Biopsychology: Biological Rhythms

Question 1

What are the biological rhythms?

Answer 1

• Ultradian rhythms
• Infradian rhythms
• Circadian rhythms

Question 2

How long do ultradian rhythms last? Example?

Answer 2

Take less than 24 hours.

E.g. Sleep Stages cycle.

Question 3

How long do infradian rhythms last? Example?

Answer 3

Take longer than 24 hours

E.g. menstrual cycle, SAD.

Question 4

What research is used for infradian rhythms?

Answer 4

McClintock: Samples of pheromones from women’s armpits. Suggests menstrual cycle may be influenced by exogenous factors.

Question 5

What does SAD stand for?

Answer 5

Seasonal Affective Disorder.

Question 6

What is SAD?

Answer 6

Occurs when longer nights. Melatonin secreted in pineal gland at night. Linked to increase in depressive symptoms.

Question 7

How many stages of the sleep cycle are there?

Answer 7

4/5

Question 8

What is stages 1+2 of sleep cycle?

Answer 8

Person is in light sleep - can be easily woken.
Breathing and heart rate slows down.
Brain patterns become slower.

Question 9

What happens in stage 3+4 of sleep cycle?

Answer 9

Deep sleep. Brain begins to produce slow delta waves.

Rhythmic breathing.

Question 10

What is stage 5 of sleep cycle?

Answer 10

REM: Rapid eye movement. Brainwaves speed up and dreaming occurs.

Question 11

How long does each sleep cycle occur?

Answer 11

90 minutes.

Question 12

What are negatives of sleep stages?

Answer 12

Individual differences - not everyone will have the same sleep pattern.
Study in controlled lab setting may be invasive not representing ordinary sleep cycle.

Question 13

What is a circadian rhythm?

Answer 13

Any cycle that lasts 24 hours.

Question 14

What are biological rhythms regulated by?

Answer 14

Endogenous pacemakers and Exogenous zeitgebers.

Question 15

What are Endogenous pacemakers?

Answer 15

Body’s internal body clock that regulate biological rhythms.

Question 16

What is an example of Endogenous pacemakers (EP)?

Answer 16

Suprachiasmatic nucleus (SCN) - detects light, even when eyes are closed.

Question 17

What are Exogenous zeitgebers (EZ)?

Answer 17

External factors in the environment which reset our biological clocks e.g. light.

Question 18

How do endogenous pacemakers affect sleep-wake cycle?

Answer 18

SCN (master clock) receives info about light from optic nerve. Sends signal to pineal gland - increased melatonin at night.

Question 19

What case study supports endogenous pacemakers?

Answer 19

Michel Siffre - spent 61 days and nights in a cave. No EZ’s (lights, clocks). Only influence was body clock.

Question 20

What did Michel Siffre find?

Answer 20

His sleep-wake circadian rhythm extended to 25-32 hours.

Question 21

What can we conclude from Siffre’s study?

Answer 21

Without EZ’s, our biological rhythms still operate, however they become out of synch with the 24 hour day.

Question 22

What are EZ’s responsible for?

Answer 22

Responsible for resetting the body clock each day, keeping it on 24hr cycle.