In the recent Hollywood blockbuster, Inception, the audience is given a moment to reconsider through new eyes an everyday phenomenon--dreaming. Today, great advances in neuroscience research by pioneers such as J. Allan Hobson (Harvard), Robert Stickgold (Harvard), Matt Walker (Berkeley), and Antti Revonsuo (University of Skövde, Sweden) have led to a plethora of new insights regarding the liaisons among dreaming, cognition, and the brain. (The reader interested in dreaming research should consult the work of these pioneers; click here.) Much of these observations stem from careful laboratory experiments requiring fancy technological approaches such as electroencephalography and neuroimaging. But the film allows one to appreciate that truly remarkable observations about dreams can be made at home, by simply reflecting upon the kinds of things that occur regularly in one's dream world, the place where one spends roughly one-third of one's lifetime.
For example, the film illustrates in dramatic fashion that our dream environments (composed of, say, buildings, natural scenes, or fantastical landscapes) are all creations of our brain, somehow. Some of these creations are as enchanting as a science fiction film by Lucas or as dramatic as a tragedy by Coppola. As mentioned by Leonardo DiCaprio's personage, in our dream world, we do not consider such landscapes and other creations to be 'self-generated,' though of course both the dream setting and the image of ourselves within the setting are fabricated by the same brain. Other components of the dream world, such as decisions, preferences, and 'action selection' can be construed as 'self-generated.' Aspects of these self-generated processes resemble those of waking life: Deciding which alley to run down when escaping a foe is a similar deliberation in a dream or in waking life.
The film also allows one to appreciate that many aspects of the dream narrative can be irrational. For instance, I recently had a dream in which I was fishing with a friend, only to moments later be giving a lecture on 'memory and the brain' in a university classroom. (It was a university that I had never visited nor seen on television, but, for some reason, this did not grab my attention; I just kept on lecturing.) Such non-sequitur series of events do not happen in reality, primarily because sensory inputs from 'the world out there' constrain the creations of the mind. The mind is not a passive entity, but a creative one, much like a film producer. According to Hobson, one fails to detect non-sequiturs and other absurdities in dreams because the higher-level, rational centers of the brain (such as prefrontal cortex) are less activated when dreaming than when being awake. (This is in contrast to many other parts of the brain, which, surprisingly, are more active during dreaming than waking.) Figuratively speaking, the narrative or 'melody' of the dream can be irrational.
At the same time, many aspects of the dream experience are lawful. For instance, in one snippet of dream time, eye-glasses in my 'fishing-to-lecturing dream' were always on people's faces and were never floating in mid air. And apples were red (as they should be), chairs were on the floor (as they should be), and what I was scribbling on the blackboard during my lecture was white chalk on a black background. All these creations were lawful. It could be said that the appearance of things at one moment in a dream--the 'harmony' of a dream--tends to be more lawful than the dream melody. Regarding lawfulness, the film also brings attention to the fact that, upon experiencing tissue-damage in a dream, one experiences pain, even though there is no real physical cause of the pain. Such an observation can be readily made in one's dream.
This brings me to another observation, one about dreams. Perhaps it will only be in the sequel that this startling fact is brought to the attention of the audience--that the 'software' in our brain giving rise to our dream experiences is the same (or similar to) software giving rise to our experiences during waking. (See further discussion here.) In short, both the world of dreams and of 'waking reality' are magnificent creations of the same brain and the same kind of software. These creations are as enthralling and intriguing as those of Hollywood, but admission is free.