This article originally appeared on VICE UK.
Why is it that drinking and doing drugs can make some people fun, but others an absolute disaster?
While one of your friends might have to be regularly held back from swinging at a bouncer, another might get horribly weepy after a certain amount of alcohol. The shy, retiring one of your group could suddenly turn into Conor McGregor's even cockier long-lost twin, while the loud one might become exceptionally earnest and tell you in detail, for much longer than necessary, why it is you mean so much to them as a friend. Others—the majority, in fact, unless you're really unlucky and have a shitty group of friends—will just enjoy themselves in a slightly louder way than usual.
We know all this to be true, but what we don't know is why people who've all ingested pretty much the same mind-altering substances behave in such different ways when those substances take hold. Is it that drinking and doing drugs bring out what's hiding within? Are certain people predisposed to specific reactions? And is there anything that can be done to alter or prevent these outcomes?
Dr. Raffaella Margherita Milani—the course leader in Substance Use and Misuse Studies at the University of West London—says there are many factors that determine how drugs affect an individual: genetic makeup, physical characteristics, age, gender, mental state, etc. How fast or slowly we metabolize drugs such as MDMA will affect how positively or negatively we react to the drug's effects.
Jeremy Frank, an addiction psychologist, agrees. He says that while the exact science of how drugs and alcohol affect our brains and bodies differently is unknown, "we do know that different drugs affect different areas of our brains and different neurotransmitters and other hormones—but it also appears that the same drugs might cause some people to experience a surge in dopamine while others might experience a surge in serotonin."
"Our chemistry is just so vastly different from person to person," he adds, "and this is part of the reason why one person might experience one drug's effect one way and another might experience a completely different impact or effect."
While cold hard science goes some way to explain the different effects drugs and alcohol have on different people, the answer mostly lies in psychology.
Frank says that, partly, "our expectations also play a role in how drugs or alcohol affect us," and that "one person might have certain expectations for what alcohol or drugs might do for them, and another might have completely different ideas, and those ideas, expectations, or 'cognitions' might actually influence and predict what experience or result we get in a self-fulfilling way."
He adds that "if you think pregaming before a party takes the edge off or relaxes you, there is a good chance that that is true. If you think using cocaine releases your inhibitions or sometimes makes your anger come out, there is a good chance that those things might happen. Throw in the very real release of inhibitions from certain drugs, like alcohol and benzodiazepines, and you definitely get impulsive behavior or a lowering of inhibitions."
Dr. Milani agrees, saying that "expectations, previous experiences, and personality traits also influence the way individuals experience substances—for example, those who are more sensitive to rewards and are sensation seekers are more likely to report more intense positive experiences on stimulants, but they are also more likely to develop addiction to these substances."
So drugs can have wildly varying effects, depending on all those factors. However, if you're just talking about alcohol, the answers are clearer.
As alcohol's main effects are to increase impulsivity and lower inhibition, the behaviors that are already brimming under the surface are likely to come out. Milani says that while alcohol can make us more euphoric and friendly if a person is impulsive and aggressive, they’re more likely to take the first swing when they’re drunk than someone who is usually more chill. As alcohol also reduces our perception of risk, we’re more likely to engage in negative behaviors.
Dr. Kate Blazey, consultant psychiatrist at Addaction, says that while alcohol and drugs will reduce our anxiety and help us to relax after the initial drink or bump, after a while, there is likely to be an "enhancement" of our underlying mood state. For example, if someone is depressed, they are likely to feel more depressed the more they drink. If, before you start drinking, you’re feeling friendly, or weepy, or euphoric, these feelings are likely to be exacerbated as you get more fucked up. With stimulants like cocaine, users are likely to feel more aggressive and agitated—feelings which will, naturally, be more pronounced if you’re already a person prone to feeling aggressive and agitated.
According to Jeremy Frank, there's little research to confirm that drugs might actually enhance personality variables or tendencies toward certain behaviors that are already inherent in a person. However, he believes that it's only because they release one's general inhibitions that underlying personality factors can be exacerbated when people drink or use drugs. However, he adds that this is because, oftentimes, "one uses the fact that they are high or drunk as an excuse to behave a way that they might want to behave anyway."
Ultimately, then, alcohol and drugs lower our inhibitions and our perception of risk, which is why we might act in ways we'd usually avoid. Why certain people act in the very specific ways is still fairly unclear, but chances are it has a lot to do with how they're already feeling before substances are ingested.
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