There's no neural fix for reversing the dependency pandemic. Using psychoactive drugs to enhance experiences is as old as humanity itself, and in the majority of cases, this doesn't lead to self-destruction. But they can also become a quick fix by activating and manipulating neurochemistry in a way that few natural stimuli can compete with. Judith Grisel, a professor of psychology, uses her own experiences to delve into the complexity of our brains and the causes and consequences of addiction. Here she reveals how the inability to treat substance use disorders stems from a narrow-minded view that brains and genes are their real cause. "Of the relatively few discoveries linking DNA sequences to substance use disorders, the biggest hits turn out to code for liver enzymes. Though these might be statistically significant, I'm pretty sure my problems had more to do with what drugs did above my neck, than below. In retrospect, it should have been obvious that genes don't cause complex behaviours such as those underlying addiction. Instead, as we now know, genes tip scales of sensitivity to shape a range of responses to our environment. It's nature via nurture, as Matt Ridley put it in 2003, not one or the other."