biopsychology - infradian n ultradian rhythms.

Question 1

What is meant by infradian rhythms?

Answer 1

A type of biological rhythm which has a duration of over 24 hours, may be weekly, monthly or annually.

Question 2

What are examples of infradian rhythms?

Answer 2

• female menstrual cycle in humans.
• seasonal affective disorder (SAD).

Question 3

What is the menstrual cycle governed by?

Answer 3

Monthly changes in hormone levels which regulate ovulation.

Question 4

How long does the menstrual cycle last?

Answer 4

Approx. 28 days from the first day of period to the day of the next period.

Question 5

What is the menstrual cycle regulated by?

Answer 5

Hormones (endogenous).

Question 6

What occurs during the menstrual cycle?

Answer 6

• oestrogen increases to cause the ovary to develop an egg and release it (ovulation).
• progesterone thickens the womb lining which prepares the uterus for pregnancy.

Question 7

What exogenous factors may affect the menstrual cycle?

Answer 7

• health.
• age.
• physical activity.

Question 8

What is an example of an infradian rhythm?

Answer 8

The menstrual cycle.

Question 9

What did stern and mcclintock believe?

Answer 9

The menstrual cycle can be influenced by exogenous factors such as the cycle of other women [synchronization from pheromones]

Question 10

What was the aim of the stern and mcclintock research?

Answer 10

To investigate whether exogenous factors can influence the menstrual cycle.

Question 11

What was the **procedure* of the stern and mcclintock research?

Answer 11

1. the sample consisted of 29 women who had irregular periods.
2. samples of pheromones were taken from women at different stages of their menstrual cycle, via a cotton pad placed in their armpit which were worn for 8 hours.
3. the pads were sterilised and rubbed on the upper lip of the other women.
4. one day one, pads from the start of the menstrual cycle were applied to all 20 women, on day two they were given the pad from the second day of the cycle and so on.

Question 12

What was the **finding* of the stern and mcclintock research?

Answer 12

68% of women experienced changes to their cycle which brought them closer to the cycle of their ’odour donor’.

Question 13

What was the **conclusion* of the stern and mcclintock research?

Answer 13

Exogenous zeitgeber such as the cycle of other women can lead to menstruation synchronisation.

Question 14

What is meant by seasonal affective disorder (SAD)?

Answer 14

Form of depression.

Question 15

What is meant by seasonal affective disorder (SAD)?

Answer 15

Form of depression.

Question 16

When are seasonal affective disorder (SAD) symptoms triggered?

Answer 16

During winter months due to reduced daylight hours.

Question 17

What is the link between melatonin and seasonal affective disorder (SAD)?

Answer 17

• hypothesised that the hormone melatonin is involved in the onset of SAD.
• melatonin is secreted by the pineal gland until dawn where there is an increase in light.
• lack of light means secretion process happens for longer.
  ↳ influences the production of serotonin in the brain.

Question 18

What is meant by ultradian rhythms?

Answer 18

A type of biological rhythm which has a duration of less than 24 hours such as the cycle of sleep stages that occur throughout the night.

Question 19

How many times are ultradian rhythm cycles repeated?

Answer 19

Every 90-100 minutes throughout the night.

Question 20

What occurs during stage one of the sleep cycle?

Answer 20

• light sleep so can easily be woken.
• slower brain waves
• muscle activity slows down.
• occasional muscle twitching.

Question 21

What occurs during stage two of the sleep cycle?

Answer 21

• between 1-7 minute.
• bursts of high frequency waves.
• still aware of sounds and activity around us.
• easily woken.
• breathing and heart rate slows down.
• slight decrease in body temperature.

Question 22

What occurs during stage three and four of the sleep cycle?

Answer 22

• waves start to slow down and become higher in amplitude and wavelength.
• deep sleep.
• difficult to be woken up.
• rhythmic breathing.
• limited muscle activity.

Question 23

What occurs during stage five of the sleep cycle?

Answer 23

• fast activity of the eye under the eyelid.
• brain becomes very active.
• dreaming and deep sleep.
• heart rate and blood pressure increases.
• body temperature increases.
• muscles relax.
• breathing is rapid and shallow.

Question 24

What is stage one of the sleep cycle’s waves called?

Answer 24

Theta.

Question 25

What is stage two of the sleep cycle’s waves called?

Answer 25

Sleep spindles.

Question 26

What is stage three and four of the sleep cycle’s waves called?

Answer 26

Delta waves.

Question 27

What is stage five of the sleep cycle’s waves called?

Answer 27

REM sleep (rapid eye movement).

Question 28

What is a strength of infradian rhythms?

Answer 28

A supportive evolutionary explanation therefore menstrual synchronisation is an adaptive strategy.

Question 29

What is a strength of ultradian rhythms?

Answer 29

Supportive research providing credibility for the stages of sleep theory as it provides supporting evidence which increases the reliability of the REM explanation.

Question 30

What is a strength of the understanding of seasonal affective disorder (SAD)?

Answer 30

• understanding the implications of SAD leads to the development of treatment which is phototherapy
  ↳ positive application helps improve mood and daily functioning of individuals improving their quality of life.

Question 31

What is a weakness of the menstrual cycle?

Answer 31

Early synchronisation studies may have confounding variables involved in the research that have not been considered lacking internal validity.