Interesting Insights from the Neuroscience of Dreaming
When you sleep, your brain is reconfigured: the imaginative1 and visual2 parts are dialed way up.
Your prefrontal cortex, which is the fact-checker, the part says “That’s not right” when you’re told something silly, is shut off3. The prefrontal cortex is also the decision-maker, the thing you rely on to make decisions in daily life like, “Should I have tea or coffee?” Because it’s off, you often don’t make decisions in dreams. For example, in real life, before you go to the railway station, you have to make an explicit decision to leave home and head there. In dreams, it often happens spontaneously. The dream just flows and you’re carried forward with the story. As if you’re watching a movie where the story plays out even if you as the viewer don’t decide anything. Except that in a dream, you’re in the movie, not watching it on a rectangular screen.
The emotional part of your brain — the amygdala — is sometimes dialed way up4. But sometimes dialed down to zero. For example, in my real life, I lost someone dear. One night, I dreamt that I was in front of her and she was dying in front of my eyes, but the emotion had been drained out. In fact, it was less emotional than watching a stranger lose his loved one. Because it didn’t hurt, it was a dream and not a nightmare. My brain was trying to understand what the process of death is like without being overwhelmed by emotion (which would defeat the purpose). Imagine you go a restaurant and something really bad happens: say something falls on your head and you’re hospitalised for a month. After you’ve recovered, you may develop a fear of that restaurant. If you do, it may be worth going back there for a meal to reassure yourself that “This place isn’t as scary as it seemed”. Similarly, my dream softened the event and brought me a bit of peace.
The part of the brain that handles short-term memory is starved of glucose5.
When you dream, you become a different species. You couldn’t experience life that way when you’re awake if you wanted to.
Here’s what Michio Kaku says on the science of dreams.
This is why dreams are so imaginative, coming up with scenarios you’d never think of when awake.
This is why dreams are so strikingly visual, like a bridge that’s so high it looks like it’s up in the sky.
This is why we uncritically and wholeheartedly buy into these outlandish scenarios.
This is why dreams have such an emotional impact, which we can recall years or decades later.
This is why dreams don’t have continuity: I once had a dream where I went to a railway station and there was a big room, like the waiting rooms you find in stations. I entered it, and my physics lecturer from college was teaching a class, and the students in the room were my classmates from college. Since I was in a classroom, I sat down and began listening to the lecture.
If you think about, the first step (going to the railway station) and second step (finding a room) fit together. The third (finding a physics class) fits with the second (finding a room) — after all, it’s reasonable for a physics class to be conducted in a room. But the third step doesn’t fit with the first. This happened because my short-term memory in my dream was limited to only one step. By the time I reached the third step, I forgot the first step (that I was at a railway station) and so attending a class didn’t seem out of place.