The Science Of Addiction

We can get hooked on loads of things, from substances to the rush from behaviors like shopping and online gaming — even ones that start off healthy, such as exercise. Here, we comb through what happens in our bodies to reel us in and what it takes to break free

- Marisa Cohen

So what is addiction, anyway? We've all said it: “I’m so addicted to salted-caramel lattes/This Is Us/my new dry shampoo.” Yeah, no. While you may love and even overdo things like that, it’s when you become so preoccupied with a substance or behavior that you’ve lost control over it — and you keep pursuing it despite negative consequences to your health, relationships and finances — that you’ve crossed over into the addiction zone.

This happens due to the brain’s plasticity—repeated exposure to environments and behaviors changes the way the neurons talk to each other, locking in certain reactions and routines. Here’s how: The first time you try a shot of vodka or pop a pill, a rush of the neurotransmitter dopamine floods the pleasure center of your brain, making you feel more confident, more aroused, less anxious. “But addictive substances hijack the system by spiking dopamine levels even higher than natural rewards do,” explains Kelly Dunn, Ph.D., an associate professor of psychiatry and behavioral sciences at Johns Hopkins Medicine. Over time, the brain is rewired so you need more of the drug, drink or behavior to get a buzz, and the stuff that used to make you happy starts to feel comparatively dull and joyless.

The worst part is, as those neurons get rewired, you start needing more and more not just to get high, but to keep from dropping into the physical and emotional abyss of withdrawal, so you may become physically as well as psychologically dependent. Eventually, a person who is hooked on a substance uses merely to keep from feeling bad, and intense cravings are triggered by the anticipation of taking it — the smell of the liquor, the sight of white powder. This makes quitting incredibly hard.