Studying dreams and dreaming is a very useful way of helping us to study consciousness. In particular what is consciousness, and where does consciousness come from?
Dreaming is definitely one way you can start to answer these questions. REM sleep is almost like a second state of consciousness. Our waking consciousness and our dreaming consciousness are very different. So one thing you can do is compare what’s happening in our brain when we’re awake and when we’re in a dream, because we know that subjectively these are two very different conscious states.
"The amount of REM sleep that you have varies during your lifespan – a baby seems to spend all their time in REM sleep. As you get older the amount of REM sleep decreases."
If we can look at these different objective measurements of brain function and so on, then we can get an idea of the systems that are necessary to facilitate waking consciousness by their absence in dreaming. In REM sleep or when we’re dreaming, the frontal areas of our brain are de-activated compared to when we’re awake – so that’s an interesting area for studies.
Another interesting area to study is lucid dreams, because they’re a halfway bridge between dreaming and being awake. So you’re still having this very internal, very subjective experience of a dream, but you’ve actually regained some of the faculties of being awake. You have insight into the fact that it’s a dream, and you can control its content, you can make memories from your waking life and here we find that these frontal areas of the brain become reactivated again during lucid dreaming. Not quite to the same amount as when we’re awake, but certainly higher than when we’re dreaming.
"Current thinking is that problems with REM sleep can be a predictor of memory disorders. When REM sleep starts to fail it can lead to problems with memory while awake, conditions like Alzheimer’s."
One of the things that happens when people start to learn how to lucid dream is that you wake up – that’s common. It can be hard to remain in that halfway state. So that’s interesting because we’re looking at correlating brain activity in these states. Another study has fund that if you can make some mild stimulation across the frontal cortex you can actually increase the amount of lucidity in a dream.
The amount of REM sleep that you have varies during your lifespan – a baby seems to spend all their time in REM sleep. As you get older the amount of REM sleep decreases. So REM sleep is considered important for brain development. Talking about conditions such as Alzheimer’s, REM sleep is much more messed up. People don’t seem to get a sustained period of REM sleep.
Current thinking is that problems with REM sleep can be a predictor of memory disorders. When REM sleep starts to fail it can lead to problems with memory while awake, conditions like Alzheimer’s.
It can be hard to distinguish between what we mean by REM sleep and dreaming – it’s easy to measure REM sleep objectively. But dreaming is entirely subjective. But it’s worth looking at reports of problems with REM sleep as people get older and degenerative illnesses.