The new science of sleep and dreaming

According Dr James Pagel of the University of Colorado, who has studied sleep and dreams for over 40 years, the advent of electronic imaging is fundamentally changing our understanding of sleep.
Dr Pagel says that while this might frightening for those who are tied to a set belief system, it's very exciting for those in the field.
It's long been known that the stages of sleep are defined by different levels of electrical activity in your brain. After moving through quiet wakefulness to stages one and two, you reach deep, slow wave sleep.
Then, the final REM sleep has some unusual characteristics. Although you are still deeply asleep, your eyes move rapidly beneath their lids, all your body muscles are paralysed and you have no temperature regulation. The whole sleep cycle takes about 90 minutes and it repeats throughout the night.
The fact that the type of dream you have varies according to the stage of sleep you are in is a more recent discovery.
The dreams you have when you're falling asleep are called hypnagogic dreams. They are very visual and intense, almost like hallucinations, but lack a narrative.
The dreams of REM sleep tend to be long, story-like narratives that often closely resemble the waking state, while light sleep dreams are often rambling, unfocused regurgitations of the day's waking activities.
In contrast, the dreams of deep sleep are often bizarre, strange events coming from deep in the mind and are sometimes are more akin to sleepwalking. They can include night terrors, extreme body sensations and intense but undeveloped thought processes.
Related: The lucid dreamers
It’s been a widely held view that dreams only occur during the REM phase, but Dr Pagel says there was never been any proof of this, and that REM sleep can occur without dreaming, and dreaming can occur without REM sleep.
Seeing REM sleep as separate to dreaming has philosophical implications, Dr Pagel points out, because it suggests the biological brain and the mind are not the same thing. He describes dreams as 'tunnelling between the body and the mind'.
‘The interesting thing about dreams is that they have a component which is apparently not biologic,' he says. 'There are characteristic components of each dream. There are the visual components, the images we see. There are the memories, all of which somehow are in our system that we've incorporated into our dream stories. And then there are emotions.’
‘Those three components of the dream clearly have biologic structures and markers, neuroanatomy, electrophysiology, neurochemistry, things we very well understand.’
‘But there are components of dream which are mind-based. In other words, we use our dreams in creative process, we use our dreams in art, we use our dreams in understanding in ways that we don't attain with conscious thought.’
‘These appear to be mind-based correlates that we can see within a dream. Now, most dreams may not show those. Most dreams are reflections of our waking life. But some dreams can be very special.’
Dreaming and creativity are often linked, and to investigate this, Dr Pagel conducted a survey of artists, directors, screenwriters and actors working at Sundance Film Labs in the United States.
‘It was kind of amazing how much they used dreams in their work. It was also amazing that there was a difference based on individuals’ creative interest. In other words, directors used their dreams in responding to change in stress, screenwriters used their dreams in decision-making, and actors just used their dreams across the board. No one uses their dreams like an actor.’