Insomnia

Today we looked at explanations for insomnia. We discussed whether it is helpful or not to use the primary/secondary insomnia distinction - Ohayon & Roth's study suggests that it might be best to always treat the insomnia first, whether or not it is a symptom of something else. We discussed precipitating/perpetuating/predisposing factors, and also the diathesis-stress model - more of this tomorrow. 

Today's powerpoint is here.

Tomorrow we have our timed essay on the restoration theory, and also the last bit of the sleep topic.

Lifespan changes in sleep

We looked today at how sleep changes over the human lifespan. You drew timelines and then we discussed the evaluative material for each stage. This is a straighforward topic that gathers together material we have already studied. Today's powerpoint is here. 

Our next timed essay is next Wednesday, 22nd October, period 3. The title is:

 Outline and evaluate restoration theory as an explanation of the function of sleep

(8+16 marks)

A suggested plan is here.

Restoration theories of sleep

Today we looked at the second theory of sleep - the restoration theory - which suggests that sleep is for our body to restore itself after the day's activities. Oswald is the main proponent and he suggested that REM was for brain restoration and SWS is for bodily restoration. We looked at the evidence for this, and concluded that the REM/brain restoration link was better supported.

We looked at two sleep deprivation case studies, to see whether the lack of sleep could provide clues as to it's purpose. There is plenty of information on Peter Tripp and Randy Gardener out there; here is a sample about Randy Gardener.

Today's powerpoint is here.

Your next timed essay will be on the restoration theory of sleep. This will be on Wednesday 22nd October.

Mrs Watson

Evolutionary explanations of sleep continued...

Today we looked at the second evolutionary explanation - energy conservation. Sleep is constrained by predator risk, and research found that prey animals sleep less than predators, presumably for this reason. This reason isn't wholly satisfactory for various reasons - we discussed the fact that evolutionary arguments are non-falsifiable, and in this case can be used to prove entirely contradictory behaviour (eg you could argue that staying asleep is a good way to avoid predators).
The powerpoint is the same as yesterdays, on the previous blog post.
Don't forget to bring your sleep diaries in next Tuesday (21st).

Evolutionary theories of sleep

Today we looked at the first evolutionary theory of sleep - that of energy conservation. This says that sleep is for energy conservation, but there are various problems with the theory and we spent a long time discussing these. It's probably the case that sleep evolved for a variety of reasons, that differ across species, and no-one theory will satisfactorily answer the question of why we sleep.

The key studies supporting this study (Zeppelin & Rechtschaffen, and Allison & Cicchetti) are correlational only - so very difficult to prove cause and effect.

The powerpoint on evolutionary theories of sleep is here - we haven't finished it all yet - there is more to come!

The nature of sleep

Today we looked at the nature of sleep and it's normal characteristics, both in humans and animals. This is pretty straightforward stuff and the powerpoint is here. 

We also spent some time looking at our essays and how to improve them for next time. The next timed essay will be on Tues 7th Oct, on shift work and jet lag, and I handed out plans today. A copy is here. Don't forget my comments on improving AO2 and cutting down on unnecessary AO1 detail.