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Dreams are perhaps the most puzzling experiences we have. What are they for? Why does the brain construct these rich scenarios for us to enact while we sleep? And more important, why are they so weird?
I have recurring zombie dreams, but not the blood-curdling nightmarish kind. My zombie dreams are adventures with close escapes, prodigal head shots, and the fashioning of rudimentary MacGyver weapons. I wake up feeling like a champ.
In last night's episode, it wasn't the zombies that I woke up thinking about. Instead, I realized that I wasn't alone in my dream. There were people present who I knew in real life. A colleague from long ago, a family friend. There they were in my dream, taking part in the zombie fun, but acting completely autonomously. I noticed that I didn't have to tell them what to do or will them into action. They just quietly carried on with whatever they were doing. Moreover, sometimes they contributed in ways that I did not expect. Sometimes they provided insights that I hadn't thought of. All in my dream.
How is this possible? After all, it was my brain that generated these characters, for no other purpose than to inhabit my slumber-show, and I control my brain — so how could those characters do things that hadn't occurred to me? Were they thinking for themselves, with their own mini-minds, packed into my mind like Russian nesting dolls? Or was my brain imbuing them with intent and keeping those intentions a secret from me?
Feeling betrayed, I woke up. As often happens, I tried to re-immerse myself in the dream, hoping to sleep more. But now when I willfully imagined those characters, they were dull pastiches of their former selves. They weren't real. I was imagining them. I could control everything they did. Their actions were meaningless.
How did they lose their intent, just as I reclaimed mine? And more important, how could I, with my brain, create a personage whose behavior I seemingly could not command? To put it another way, how could I think of something that doesn't think like me?
The truth, as I see it, is that I was tricked by an illusion.
While we sleep, our brain consolidates what it has learned in the past day. Yesterday I interacted with many people: I had lunch with friends, I spoke to colleagues about work, I ordered lunch from a waitress. In all these interactions, my brain was busily interpreting other people's actions and trying to attribute intent to them: What did she mean by that? Did I offend him? How are they going to react? went my inner monologue. Although the actual intent of my peers was never known to me, deep in my brain there were groups of cells trying to predict what the people I interacted with were thinking. This ability is what some call Theory of Mind. And we learn it gradually as we grow up. Even scrub-jays are thought to have it.
Back in my dream, as I watched my zombie hunter friends and tried to find meaning in their actions, it seems that I was repeating this process. Confronted with their unpredictable behavior, I set about trying to read their minds. Does this mean that they had minds to be read? That sounds ridiculous, although that is exactly how it seems. The answer is no (of course), and this is the root of the illusion.
For my brain to make me believe that my dream friends were autonomous, it wouldn't have to actually generate autonomous characters or behaviors. Instead, it would just have to re-engage within me the Theory of Mind processes that I had spent the previous day practicing. Cognitively, the process of "reading minds" and the experience of observing autonomous behaviors are two sides of the same coin. You can't have one without the other. As my brain replayed this cognitive process in sleep, my personal experience would thus be of trying to deduce what another person was thinking without having access to their intentions, just as in real life. Only this time, there were no actual intentions there in the first place to be deduced! Just my brain going through the motions. A dry run, if you will.
This raises the prospect that the content of my dreams, the figurines which populate it for me to observe, are not what sparked my attempt to read their minds. Rather, the characters were generated precisely because my brain was rehearsing my Theory of Mind ability. The causal chain might very well be the other way around.
Perhaps even the craziest of dreams are just a consequence of our brain quietly rehearsing.
