by Sunny Biswas
I had this little kid fear well past being a little kid that I’d wake up a different person then the one I went to sleep as. As in, the thoughts I was having before going to bed would be forgotten by morning and the impostor waking up would have ones that were subtly, unmistakeably different in content and tone. What’s he going to be like, I’d wonder. Will he be smarter? Happier? Is he going to like turkey sandwiches better? Is he going to miss me?
That kid wasn’t 100% wrong, kind of. At around the same time he was learning that you don’t grow new brain cells when you grow up so don’t huff paint/ride rollercoasters/bang your head on the wall, neurobiologists were finding out that the opposite was true. It turns out that in a couple of parts of the brain, neural stem cells are constantly giving birth to new neurons that travel around and plug into already existing networks. Sometimes they’re replacing dying neurons and sometimes they’re just helping a part of the brain grow. (A lot of neurons don’t get replaced at all, though, so we’re about half a ship of Theseus). There’s a body of recent literature that suggests that this is how adults form new memories. Some of it also says that depressed people are worse at doing this — important chunks of our brains stay locked into these self-destructive patterns, while healthy people have brains that are malleable enough to change.
I should say here that I realize that the literature is inconclusive, that adult neurogenesis is still a controversial topic, and that as someone who does research on the topic I know enough to be very, very cautious in how I describe the connection between small amounts of experimental data and chin-stroking thoughts about how, um, thoughts work. It’s one of the strange things about studying neurobiology that you learn a lot about the brain and end up being more careful than before in tying that into how exactly you think.
But what the hell, right? I read about neural stem cells and think about how different I am from even a few years ago, and I get the weird feeling that I was right when I was little, that I’m the most recent in a long line of not very good impersonators of myself. Science (science!) confirms that parts of me are here now that weren’t there even a little while ago (and that parts of me that were there before are gone forever). In other words: one night someone else went to sleep and woke up as me. I do a lot of the same things as him but I know that I’m not the one who came up with them. I like a lot of the same things as him but I know I didn’t discover them. Otherwise I act in ways that he wouldn’t have thought of and found new stuff to like that he wouldn’t have recognized. I’ve taken that poor bastard’s place and he barely even realized it was happening. It’s awesome.
Because I’m finally starting to be okay with getting replaced. If every impostor has to keep pieces of me (a bunch of what neural stem cells do is supply neurons to already existing networks, remember), it’s more a collaboration between me and the next guy than a theft. That makes it a little less strange and even kind of cool seeing what each one has come up with on his own. Which one of us started drinking coffee? Who finally decided to buy clothes that actually fit? I wish I could thank the guy who decided to hang out with the people I ended up spending most of my time with. And I wish I knew what the next guy is going to have to keep around and what amazing thing he’s going to be original about. None of this is true for just me, of course, because it’s the same way for everyone: part of us gets old and part of us is new all the time, and the trick is integrating both.
So when the trees or robots or lizard people from under the earth start taking over in Y2K12, I’ll miss a lot of things, not the least of which is that we never figured out how we even work. But what I’ll really miss is finding out how we’re all going to be different and how we’re going to be the same. Who’s still talking and who’s going to be that guy you haven’t thought of in forever? Who do we not know yet who’s going to be part of our group? Are Andy and April on “Parks and Recreation” going to end up together or what? Will Kanye start dressing like late period Michael Jackson? And seeing how this is the internet, let’s be really self-absorbed for a bit and think: what parts of us are going to stick around and what’s waiting to be born?
It’s too bad, really, that it’s happening so soon. That’s the shame of living this close to the end — we’ll be too much like ourselves right now by the time we’re all gone. So let me just say that I hope the me who’s going to be around for the end of the world is a better, cooler person who can relax and enjoy the spectacle. And maybe also one that can hold his liquor better.
Sunny is working in a lab in Austin that studies memory formation in adult mice. Oddly enough, this involves lots of pipetting. He’ll probably end up going to med school like every other Indian person you know. He writes stuff here.