It's ‘Never Enough’

Scott McLemee reviews Never Enough: The Neuroscience and Experience of Addiction by Judith Grisel.

April 12, 2019

The best-known saying from William Blake's The Marriage of Heaven and Hell goes, "The road of excess leads to the palace of wisdom." I am not at all sure the reader is meant to take this as practical advice. The poet moves back and forth between spiritual revelation and satire so often and so quickly that keeping track is difficult. "You never know what is enough," we read a few dozen lines later, "unless you know what is more than enough." That sounds altogether more balanced and common-sensical. But like the earlier quotation, it appears in a section called "Proverbs of Hell," a manifesto of rebellion against prudence, moderation and other boring heavenly virtues.

In her teens and early 20s, Judith Grisel took the road of excess to someplace close to the point of no return. In Never Enough: The Neuroscience and Experience of Addiction (Doubleday, 2019), she recalls the "abrupt shift of perspective coincident with guzzling half a gallon of wine in my friend's basement" at the age of 13: all "desperate strivings for self-acceptance and existential purpose" disappeared, and she felt at peace and genuinely alive. The following day was another matter, of course, but she had plenty of opportunities to return to that state of mind, or at least to try.

Over the next several years, she ran the gamut of mind-altering substances -- taking as much as possible, as often as possible -- only to find each one betraying its promise of relief: "It didn't take all that long before the drug's most reliable effect was to ensure the alienation, despair and emptiness that I sought to medicate." Never Enough does not quite belong to the genre of the recovery narrative: it provides enough detail about Grisel's life as an addict to be appalling without becoming sensationalistic, while saying relatively little about how she got clean. But a turning point came when a fellow cokehead observed that they could never have too much of the drug. Addiction makes "enough" impossible.

After three decades of sobriety, the author -- a professor of psychology at Bucknell University -- takes her experience as a reference point while introducing the lay reader to the neuroscience of addiction. Her own education and laboratory work were driven by the hope of finding a cure for addiction. Today, she writes, she is "not especially hopeful about the prospects of solving something as complex and intractable as addiction anytime soon." She also find herself "increasingly skeptical that the solutions are ever going to be found solely in the brain." This admission comes after a couple hundred pages laying out some of the knowledge that has accumulated on the brain's responses to mood-altering substances. But no end is in sight.

The chemistry and physiology of the human nervous system seem almost perfectly designed for substance abuse. Find a neurotransmitter or a receptor in the brain, and there is probably something you can absorb to interfere with it in pleasurable, even ecstasy-inducing ways. But the central nervous system is self-monitoring and self-regulating, and it "counteract[s] the changes in neural activity produced by the stimulus in an effort to return brain activity to its neutral, homeostatic state." Grisel calls the changes in neural activity involved in intoxication "the a process," which elicits an equal but opposite reaction, "the b process," returning things to normal state. The b process manifests itself at various intensities depending on the substance and quantity consumed: hangovers, "crash and burn" depressions, an unbearable craving for the substance and so forth. "Generated by a powerfully adaptive nervous system," the author says, "the b process learns with time and exposure. Repeated encounters with the stimulus result in faster, bigger and longer-lasting b processes that are better able to maintain homeostasis in the face of disruption."

The more familiar term here would be "building up a tolerance." An increase in the stimulus (two lines of coke instead of one, vodka instead of an equal quantity of beer) can override the compensatory b process -- but only for so long. Furthermore, the brain's processing powers come into play: "It uses its exceptional learning skills to anticipate disruptions, rather than wait for the changes themselves, and begins to dampen drug effects before the drug has even been delivered." The brain's responsiveness can also trigger cravings for a drug when users find themselves in a place or with people they associate with the drug.

Some substances induce such a powerful disruptions in the nervous system that the compensatory process becomes agonizing; reports of the ecstasy and the crash following first-time methamphetamine use make addiction sound just about unavoidable. But many people -- most, probably -- can have a drink or smoke a joint without unleashing an escalating battle within the central nervous system that ends up in abjection. Grisel is clearly not one of them: she writes of continuing to feel cravings for various substances she hasn't touched in 30 years. "Even today," she writes,

I’m confounded by people who can drink or use other drugs but don’t. For me, and others like me, nothing short of impending doom (and often even that) would provide enough incentive to forgo pharmacological stimulation. People who stop after only one drink, mete out cocaine like a banker or keep a bag of weed around for months are entirely foreign to my experience and beyond my capacity to comprehend. On the other hand, I am able to relate to the depravity in this story from the Associated Press: "Man Accused of Trying to Swap Baby for Beer." Apparently, someone called the police after this man offered her a 3-month-old baby in exchange for two 40-ounce beers. I’m sad to say that I really do understand the perversion of values that enables such an insane proposal, and while responsibility has to be attributed to the addict, it seems obvious that no person in what might be called a "right mind" would do such a thing.

What determines whether an individual has that kind of susceptibility? Grisel notes the appeal of a seemingly logical approach to the problem: behavior leads back to neurophysiology, which leads in turn back to the human genome, where one day we might locate the sorts of markers that indicate someone prone to taking the road of excess to an early grave. Grisel's sense of progress is much more somber: "It seems to me that the more deeply we look at anything, the more complex and mysterious it becomes. It’s as if with each additional data point, our realization of how very little we understand increases proportionately; like an onion that grows as it’s peeled." She identifies four types of factors seemingly in effect in creating the sort of bottomless addiction that might well have killed her: besides genetic susceptibility, they include binge consumption, the unfinished development of the brain during adolescence and "a catalyzing environment," including obvious influences such as childhood abuse or a lack of positive role models. "It's not necessary to have all four," she writes, "but once some threshold is reached, it's like breaching a dam -- virtually impossible to rebuild."


Be the first to know.
Get our free daily newsletter.


Back to Top