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I've been talking to a young man about his drug issues, and he feels he's got a serious dilemma to unravel. Lately he's been taking dissociatives -- dextromethorphan (DXM) and ketamine -- and they get him to a place he can't seem to find without them.
Charles (I'll call him) is in his early twenties, bright, energetic, and a bit lost. He's tried a number of jobs and hobbies, a little time at university, and lately quite a few drugs. He seems to have a healthy fear concerning really nasty drugs like meth, crack, and heroin. But dissociatives are freely available among his friends and at the local drugstore, they don't come with a heavy price tag, either in terms of money or raised eyebrows, and they don't seem very dangerous to him. In fact I'm not aware that there is a toxic dose for these drugs, though you can sure make yourself sick. And brain damage does not seem likely, but it wouldn't be that hard to kill yourself if you stumbled around in traffic or fell down the stairs.
What dissociatives do to your mind and brain.
Dissociatives do exactly what their name suggests. They break down associations between current experience and all the reference points, memories, and meanings that normally make experience make sense. Experience that pulls away from sense is a liquid haze of emotions, impressions, and shifting boundaries between the real and the imagined. Take enough and those boundaries disappear for hours at a time. Take more and you lose control of your muscles as well: you can't walk or talk normally, if at all.
Dissociatives work by blockading NMDA receptors all over the cortex. These are entry ports into neurons that allow for communication among distant cortical regions. But NMDA receptors have a special function: they don't just pass on any information; they transmit information that allows the cortex to make sense. They help the cortex -- the part of the brain that thinks and plans -- to fit present experience to a sensible model of the world. In other words, they might not be much good for interpreting abstract art, but they tell you what you're doing, where you're doing it, when you started doing it, and why it makes sense to be doing just that. This is pretty important for day-to-day living. But it gets seriously messed up with DXM or ketamine (or PCP or angel dust). Now you can experience things the way they seem to be or the way you want them to be. With your cortex in disarray, meaning might get formed by more primitive parts of your brain, like the limbic system and brain stem, without the usual "reality testing" that shapes experience into something familiar.
Charles was not surprised when I shared this with him. But his dilemma remains. There are times when he's on these drugs that he feels completely free of the constraints, values, and habits he's been enslaved by (so it seems to him) for most of his life. The rules by which he conducts himself, his constant efforts at impression management, and his sometimes suffocating need to be "good" dissolve into a mist of spontaneity and adventure. He can let himself be himself, his real self -- the true self that, as he puts it, has been out of reach for his whole life. So his question is this: I know I get there through drugs, I know it's a short-cut, and I know it won't last, but isn't there something productive, even wonderful, at finding my true self, even for a few hours?
I'd like to know your thoughts about this. I'll tell you what I think in Part 2, coming in a couple of days.
(Additional posts on similar topics (with more personal and neuroscientific detail) can be found on the Memoirs of an Addicted Brain blog/website.)
