The Evolutionary Advantages of an Addictive Personality


The devastating consequences of substance abuse pervade the daily news, undermine efforts at work, and rob our pocketbooks as well as our families. Scholarly, educational and political efforts so far have failed to stem the tide; more of us are using than ever before, and we are using more. For at least one in eight Americans, too much chemical conjuring is still not enough, and as the costs of drug use outpace the gains, many of us eventually find ourselves in treatment, prison or dead. Perhaps even more sobering: the consequences of pervasive drug use span generations: millions of children live with addicted parents, and fetal exposure to mind- and development- altering substances is at an all-time-high.

We’re so inundated with bleak facts about addiction that it may be hard to perceive any silver lining. It’s nearly impossible to imagine, but there could be an evolutionary advantage to the addictive tendencies that cause many to throw away relatively safe and undisrupted lives to walk on addiction’s perilous ledge. As a former addict who is now a psychology and neuroscience professor at Bucknell University, I've dedicated my life's research to learning the root causes of addiction.

The first clue can be found in plain sight: the very commonness of addictive disorders suggests their tendency might not be entirely disadvantageous. In contrast to rare diseases, which are often the result of spurious mistakes in gene transcription or singular insults, the prevalence of drug use disorders indicates they are selected for, rather than against, by evolutionary forces. Indeed, the biological factors and behavioral tendencies that precipitate such havoc have their source in causes not only ancient but (certainly at times in our species’ long history—and perhaps even today) helpful.

Of course, we haven’t evolved a proclivity for gulping toxic molecules, or an inclination toward injecting the exudate from unripe poppy seeds, or any number of other striking strategies for muting and mutating consciousness, in and for themselves. Genes and other inherited factors usually work by setting the stage upon which our circumstances play out. So, we might ask, what exactly is the biological tendency to use and abuse mind-altering chemicals reflecting, and how is our environment catalyzing this predisposition?

Though something as complex as addiction certainly doesn’t have a sole cause, some of us are prone to it because we are predisposed to especially appreciate new experiences. Where someone naturally more cautious might retreat from novel and potentially risky opportunities, addicts and potential addicts are more inclined to perceive them as a pleasurable break in the humdrum. And sensation-seeking varies within individuals and between them. We’re generally more likely to find new and risky experiences pleasurable during adolescence, which happens to be the time when most substance-use disorders begin.

A core attribute of addictive drugs is that they are neurologically newsworthy, and for sensation-seekers, they may satisfy a craving like scratching an itch. Though a tendency to spend the rent money on a transient solution to boredom might be hard to fathom as a parent or partner of such an individual, from an evolutionary perspective, such tendencies may be a real asset. The population benefits by having a mixed pool of risk-averse and risk-seeking individuals—some to caution us to remain secure in what’s familiar, and others eager for the unknown. Which is better for survival clearly depends upon the particular conditions; at least some of us will survive if the group expresses tendencies toward both strategies.

Over the past several decades a large body of research has documented that an innate attraction toward novelty predicts drug use, abuse and addiction. The rising incidence of substance-use disorders suggests that innate tendencies are being increasingly roused by environmental triggers. This means that addiction is a consequence of the biologically driven states inherent in a great many of us, and also suggests that disordered use might be mitigated by more opportunities to purpose this tendency in healthy ways. Indeed, our circumstances are both more likely and easier to change than internal factors.

While many of us might find deep satisfaction in the daily rhythms of work, caring for ourselves and our families, and watching our gardens grow, for others, these joys seem like lockboxes serving as reminders of the relentless tedium of living and therefore prompts for “burning down the house.” New and challenging opportunities our distant ancestors regularly encountered, like stalking dinner, dealing with unexpected weather events or giving birth alone in a forest, are hardly commonplace for the average North American

With little opportunity for exploring new horizons, many might be inclined to seek excitement through direct manipulations of neurochemistry. Perhaps by developing alternate channels for the natural drive for new experiences and challenges to flow, the need to seek exciting states in chemical fixes would diminish. Even better, society as a whole might benefit as novelty-seekers trailblaze for us all.