Alcohol is a very simple molecule with incredibly complex effects. Although I already knew a bit about the neurobiology of alcohol, I just spent an afternoon reading a dense journal article that described roughly 50 different neural mechanisms it affects. After which I felt like I needed a drink. It’s widely known that alcohol reduces stress temporarily, and many people use it for just that purpose. It reduces stress by increasing the uptake of aneurotransmitter called GABA, the brain’s primary inhibitory molecule. (And by “inhibitory” I don’t mean that it makes you feel inhibited. Quite the opposite, of course.) By sending more GABA to your brain cells, alcohol works much like common tranquilising drugs such as Valium and Xanax. That’s why you start to stumble and slur if you drink too much. But alcohol acts on many other neurotransmitters too.
I’ll mention three important ones and show how they contribute to the joys of inebriation. While alcohol increases GABA, it reduces the uptake of glutamate, the brain’s premier excitatory molecule. Less excitation and more inhibition? That sounds like simple summation, but GABA and glutamate have different effects on different brain regions, and that’s where things get complicated. In the prefrontal cortex, the part of the brain you use for thinking and planning, the net effect is inhibition. That’s why your judgment is flawed, your decision-making is set to “whatever,” and your ability to see things from any perspective other than your own approaches nil. The remarkable side effect of this general dimming is that your thoughts seem amazingly clear – which is nice – while in reality they are just amazingly limited. Meanwhile, GABA is also busy turning off the brakes on a system that releases dopamine, the molecule that takes centre stage in all varieties of addiction. What’s that again? Well, when you take off the brakes, the car starts to move. So what you get is a stream of dopamine coursing into the striatum (or reward system), the brain part that generates desire, anticipation, and (once you’ve finally brought the glass to your lips) pleasure.
So far, you’ve got physical relaxation, which diminishes stress, reduced judgment, allowing you to talk and behave however you want, and stimulation of the brain’s reward system, which makes you feel like something nice is about to happen. But the fourth neurotransmitter tops the bill: opioids. Sometimes called endorphins or internal opiates, they get released by alcohol too. Everyone knows that opiates feel good, but did you know that you can get your opiates legally by downing a stiff drink? The American martini – which consists of three ounces of gin and little else – feels particularly nice for a very simple reason. The faster the alcohol goes in, the more internal opiates get released. Hence the aaaaahhhhh.
Given all the things that make up an alcohol high, it shouldn’t be surprising that inebriation feels different to different people, feels different from the first to the last drink, and definitely feels different once it becomes hard to stop. People who carry around a lot of stress drink to relax. People who spend a lot of energy controlling their impulses drink in order to let themselves go. The first drink of the night excites you, the last drink of the night sedates, and that isn’t nearly as much fun. College kids indulge in binge-drinking because they’re still bright-eyed novices when it comes to taking chemicals that alter their mood – the more the merrier. Twenty years later, they may drink to feel less, not more, because life has become oppressive, and anxieties seem ready to spring from every train of thought.
But once people become addicted to alcohol, as many do, the fun of the high is eclipsed by two opposing fears. The fear of going without, versus the fear of being unable to stop. That clash of concerns comes from several sources. First there are the unpleasant bodily effects that plague big drinkers when they stop for a few hours or, worse, a few days. Add to that the emotional emptiness, depression, and increased stress responsiveness that overcome the drinker’s mood at the same time. Taken together, these effects make up what George F Koob callsthe dark side of addiction. But I think the real bogeyman, the unbeatable Catch-22 when it comes to alcohol and other drugs, is the realisation that the thing you rely on to relax is the very thing that stresses you out the most. It’s hard to find a way out of the recurrent cycle of anxiety and temporary relief, over and over, and that’s the epitome of a losing battle.
People like to get drunk because alcohol smacks your brain around in a number of ways that feel pleasant, or at least different, or at the very least better than going without. And that’s really how all mood-altering drugs work. Which is generally OK, because recreational drug use, including drinking, doesn’t lead to addiction for most people. But for those who get caught, the fun soon disappears.
Drugs, including alcohol, fashion neural habits: get it, take it, lose it, then get it again. And those habits narrow the brain’s focus to a very singular goal, at the expense of everything else. The striatum – the brain’s reward system – is responsible, not just for pleasure, but more seriously, for feelings of desire. And desire isn’t fun, unless you’re just about to get whatever it is you want. Then, the more you get it, the more your striatum gets tuned by that surge of dopamine, modifying its synaptic wiring a little bit at a time until other goals just don’t count for much.
But alcohol has one advantage over drugs like heroin and cocaine. It’s legal, and socially sanctioned. In fact drinking has become deeply enmeshed with themes of social engagement, joyful celebrations and all the rest of it.
Drinking doesn’t make you a bad person – in fact it seems to put you in good company and thereby make you a good person – if you can resist its addictive lure. The problem is that people who start to drink too much get pulled by two conflicting emotional beacons: feelings of connecting with those around them and feelings of shame that toxify those relationships. That’s a conflict of interest that gets increasingly difficult to resolve. So, just as they say in the fine print on the back of the bottle: “know your limits”.