“It was like watching a movie, one where you know something bad is about to happen to the main character, and you hope that somehow he escapes danger. Except the main character was me.”
James B., The Craving Brain
James B. was an athletic, intellectually gifted, and spiritually sensitive teenager. Before he even graduated from college, he had lost control of both his drinking and cocaine use. His family and friends were left shaking their heads. Why didn’t he just quit?
James didn’t quit, because he couldn’t quit. Beginning as a weekend binge drinker in high school and drinking even more in college, he had exposed his brain to frequent high levels of addictive chemicals. This exposure severely injured his brain’s reward system.
Through chemical messengers called neurotransmitters, the reward system helps us take pleasure in everyday activities. Not surprisingly, its strongest reinforcement is reserved for behaviors like eating and drinking that directly affect our survival.
The process by which the brain rewards our behavior is linked to the neurotransmitter dopamine, the “feel-good” molecule. When dopamine levels rise, the brain signals that the associated behavior is important and should be repeated. Thanks to dopamine, we eat and drink as if our lives depend on it—and, of course, they do.
In normal conditions, the brain’s “go switch” is balanced by an equally strong braking system. As the amount of dopamine in the brain increases, a complex anti-reward system kicks into gear, decreasing the amount of dopamine and returning the brain to its natural equilibrium. Thanks to this chemical balancing act, most of us do not get trapped into compulsively repeating the behaviors that give us pleasure.
The brain’s finely tuned reward system is upended when alcohol and other addicting drugs are delivered to the brain in frequent, heavy doses. Studies show that all addictive drugs increase the amount of dopamine in the nucleus accumbens, a central coordinating area of the reward system. The sudden rise of dopamine kicks the brain’s go switch into high gear and sends out an urgent message:
Addictive drugs are important, and the behavior that delivered them should be repeated.
When casual users respond to this powerful signal by increasing their alcohol and other drug use, they run the risk of developing a pathological craving. At some point, the message from the reward system changes to:
You will die if you don’t get the alcohol or other drugs that you need.
As one heroin addict put it, “When my craving kicks in, I feel like I am 20 feet under water. I will do anything, anything to get to the surface.”
Although uncontrollable craving can develop with breathtaking speed—new research shows that cocaine can rewire the brain’s executive function in just a single use—the progression from casual to heavy use to addiction is not inevitable. Both preoccupation and escalation are early-warning signs on the road to addiction. When we recognize them as such, we can save ourselves and our families a lifetime of trouble.