So I'm sitting in a meeting, and my mind is wandering off to a conversation I had yesterday. I'm obsessively repeating the conversation in my head, detail by detail. It seems more real than the conference room I'm sitting in. I do this all the time, like when I'm trying to fall asleep. When I'm walking around, my mind is always wandering somewhere else. I know this is going to get me killed some day, after I step in front of a bus or something. Why, Science, why would my brain do this to me?
Distracted, Possibly to Death
You must not think of the human brain as a machine full of excess power and capacity. It's a cobbled-together mess, struggling to accomplish tasks with whatever resources can be mustered. This is why almost all of us are right- or left-handed (rather than ambidextrous), and it's also why our minds wander and we daydream.
It takes a significant amount of brainpower to process and comprehend the world around us. (In fact, it is still an impossible task for even the most powerful computers to comprehend a simple conversation or how to navigate a parking lot as well as the average 16-year-old.) When the external world is dull (and in all three of your circumstances—a meeting at work, lying quietly in bed, walking down a path you walk down every day—nothing interesting is going on), the brain really wants to put all that idle processing capacity to good use. Enter spontaneous thought processes—science's fancy word for daydreaming or mind-wandering.
The brain's default network is made up of the parts that light up when we're doing nothing. When we're in a boring environment, it takes hold of things and connects the world-processing parts of the brain to our memory centers, our action-planning centers, and our imaginative centers of the brain. We can pick apart memorable conversations we've had in the recent past, imagining them from multiple perspectives; plot future plans in the safety of our minds; or consider the consequences of changing the current reality of our environment—all with what would've been wasted time for the processing centers of our brain.
Science also has those 3:00-a.m. moments, when he is trying to sleep but his brain is instead replaying con-versations from earlier in the day. It is often an exhilarating experience—a bit like being in the bullet-time of the Matrix movies—and a way for those of us less socially apt to get some time to catch up and understand why everyone is always fed up with our uncouth ways.
So embrace your wandering mind. Just watch out for those buses!
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