Notes

Essay Practice:
Discuss the role of endogenous pacemakers and exogenous zeitgebers in the circadian rhythm. (30 mins)
Expectations

The examiner will expect to see a clear and accurate description of the role of endogenous pacemakers and exogenous zeitgebers in circadian rhythms. To achieve the best marks your description must be accurate and detailed. Remember to include psychological terms, describe studies concisely and write as clearly as possible.

Evaluation and Analysis

Here, the examiner is looking for your ability to analyse (break down into its component parts) the endogenous and exogenous components of the rhythm which you have described. It is time to think about the usefulness of the research by comparing it with the findings of other studies, which may support or refute the work, and take into account any methodological criticisms which may affect the validity or reliability of the study. You may bring in research into ‘consequences of disrupting circadian rhythms’ but you must make this material relevant to the question. In other words, only use it to comment on endogenous and exogenous factors.

Think carefully about approaches, issues and debates to achieve top marks. How useful is the biological approach in this case? Could other factors affect endogenous and exogenous control which can’t be explained using this reductionist and deterministic approach? Why could some of the early experiments on non-human animals not be carried out today and how does this affect future research into circadian rhythms? It would be prudent to explain that you are going to focus on the sleep-wake cycle, since much of the research into circadian rhythms has focused on this area.