biological rhythms questions from the book

Question 1

What are the strength of using EPG

Answer 1

Using an EEG is an objective measure. All the participants are monitored in the same scientific way so this increases the reliability and validity of the findings from each participant’s brainwave activity during their sleep.

A further strength is EEGs collect quantitative data that can be analysed statistically which may make it easier to draw conclusions from the data.

Question 2

What are the limitations of EPG

Answer 2

A limitation of measuring sleep and dreaming in a laboratory is the way participants behave may be different than at home. They are aware that they are being observed in this setting which could affect their sleeping patterns; the amount of REM sleep may be different at home. Their reactions may not be typical. Also being hooked up to the EEG equipment may make it more difficult to sleep because the participants may be uncomfortable.

With most sleep studies, the sample sizes tend to be very small making generalisations difficult, particularly when there are such great individual differences between participants.

The EEG does not explain why the electrical activity is taking place. The activity may not be caused by dreaming but by some other factors.

Question 3

Explain how each of the following studies can be used to support the influence of peacemaker and ziegtoabor

Siffre:

Answer 3

The ‘cave man’ studies by Michel Siffre in 1962 and 1972 support the presence of endogenous pacemakers or biological ‘clocks’ in the sleep/wake cycle as his circadian rhythm maintained a regular rhythm without the aid of any external cues in the form of light (zeitgebers).

Question 4

Explain how each of the following studies can be used to support the influence of peacemaker and ziegtoabor

Aschoff and Wever

Answer 4

found evidence for a free-running sleep/wake cycle of about 25 hours. This suggests that light has an influence on circadian rhythms. This is because the absence of light (in a bunker) meant this zeitgeber could not entrain the natural cycle, suggesting this is the normal function of zeitgebers. However, the findings also showed that there is an endogenous pacemaker controlling the sleep/wake cycle because each participant had a regular and predictable rhythm.

Question 5

Explain how each of the following studies can be used to support the influence of peacemaker and ziegtoabor

Stern and McClintock:

Answer 5

The menstrual cycle was once thought to be regulated wholly internally, by the hypothalamus (the endogenous pacemaker). However, evidence suggests that external factors (zeitgebers) can play a role in ovulation and menstruation. It is thought that women at different stages of the menstrual cycle give off different pheromones. McClintock and Stern’s findings show that the menstrual cycle is influenced by these zeitgebers, and explain to an extent how women’s menstrual cycles can come to synchronise.

Question 6

Using an example, explain what is meant by ‘exogenous zeitgeber’.

Answer 6

external factors that entrain our biological rhythms such as the influence of light on the sleep wake cycle

Question 7

Explain what is meant by the ‘sleep/wake cycle’. (2 marks)

Answer 7

A daily cycle of biological activity based on a 24 hour period that is influenced by regular variations in the environment such as alternation in the day and mind

Question 8

Briefly explain the effect of endogenous pacemakers on the sleep/wake cycle. (2 marks)

Answer 8

Internal body clocks that regulate many of the biological rhythms for example the SCN on the sleep and the sleep cycle. provides information from the eye about light, light resets the superchiasmatic nucleus. drowsy feeling at night occurs due to the superchiasmatic nucleus

Question 9

Core body temperature when is it highest and closes

Answer 9

6pm core temperature 38 degrees

4am varies around 2 celecius over 24 hours and 36 degrees