Overview
“Dopamine is an enormously important molecule in addiction, central to th experience of learning and reward prediction, but its functioning is far more complicated than it is commonly portrayed. In a way, the popular stories about dopamine still rely on a circa-1980s level of understanding… For one thing, dopamine is not a ‘pleasure’ molecule: it has more to do with the feelings of desire and ‘wanting,’ not enjoyment and ‘liking’”
Roy Wise, the neuroscientist made famous for identifying dopamine as the pleasure molecule in the wake of the American 1980s crack epidemics, actually retracted the notion that dopamine was a “pleasure molecule” after more experiments in the 1990s.
Though it might sound like an abstract, philosophical distinction without a difference, “wanting” and “liking” involve separate processes and pathways in the brain. It helps if we adopt some new terminology to reflect this separation: incentive salience and hedonic impact, respectively.
When we say dopamine pathways have been “hijacked” by chronic substance use, what we mean is that the sensitivity of the mesolimbic pathways responsible for incentives is dramatically increased in response to cues associated with a substance or process. This is what produces intense cravings; the connections between the Ventral Tegmental Area (VTA) and Nucleus Accumbens (NAc) are altered such that the NAc is flooded with dopamine that creates the want for the addictive stimulus. At the same time, the brain reduces the number of D2 dopamine receptors within the tiny hotspots in the brain responsible for the actual feelings of pleasure. When these two effects are combined with a weakened prefrontal cortex that’s responsible for controlling impulses in the service of long-term planning.
Commentary
Understanding Liking vs. Wanting
This discrepancy between wanting something without liking it is one of the most puzzling pieces of addiction to reconcile intuitively, perhaps even more so for those who actually struggle with it who can feel frustrated and discouraged by their seeming inability to improve incentive salience from consequences.
I would argue that non-Western spiritual traditions have done a better job capturing this nuance than modernist Western ontologies that have traditionally framed the self as a Cartesian mind-body system where the mind can be reformed through cognitive reframing that will dictate behavior to the body in a top-down fashion. When combined with Protestant conceptions of the self as a discrete soul created by a personal interventionist Creator, this then sets up a dichotomy: a mind whose moral obligation is to sustain the willpower to exact a rational agenda over the material temptations felt by a sinful, non-rational body. Under this model, the distinction between wanting and liking is difficult to consider since all roads lead back to a mind that must use willpower to unify wanting and liking towards sustained sobriety against the intrinsic human tendency towards sin, despite a wanting and liking for sobriety being a prerequisite to make that decision. All decisions one makes are necessarily products of a will that wanted the decision because it liked the indicated outcomes of that decision. There is a strong fixation on finding a core self or soul to hold responsible for its omnipotent agency over incentive salience.
The Pali Canon, the oldest and most complete early Buddhist literary canon that has survived for us to parse, deals in the language of cravings and attachments rather than sin and temptations. Within the Tanha Sutta (Samyutta Nikaya 45.170), the Buddha describes “tanha” as the concept of craving, which comes in three forms:
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kama-tanha, the craving for sensual pleasures
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bhava-tanha, the desire for permanent existence and reincarnation
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vibhava-tanha, the desire for self-destruction and annihilation of one’s existence
Understanding the thoughts, feelings, and behaviors under the umbrella of addiction through the three types of craving can offer a nuance that resonates more than the traditional recovery cliches, like “it’s not a drinking problem, it’s a thinking problem” followed by reminders to practice gratitudes and prayer. Kama-tanha describes the anticipatory dopamine spikes that are associated with liking the experience of a substance before tolerance numbs the rewards of using it. Bhava-tanha describes the desire to maintain the state of the intoxicated self long after the experience of using brings minimal pleasure, if any, as the brain signals that the substance is a necessity to function. Vibhava-tanha describes the desperate urge to escape the intolerable feelings of one’s current reality through substance use, even if it means dissolving one’s consciousness and agency into oblivion in the process.
If we formulate addiction in terms of tanha, we arrive at a model that’s neither a moral one nor a disease one, but a metacognitive one.
For instance, “My name is ____, and I’m an addict/alcoholic” is a standard opening members are expected to repeat as part of equalizing themselves to others in the group for the sake of unity under common identity. This actually leans into bhava-tanha by replacing one type of structure for an ego with another that’s conducive to transactions with a worldly collective. Anatta, or the concept of “non-self”, explicitly orients Buddhism against identifying with permanent or fixed characteristics. A big ontological issue within the biomedical pathologization of addiction as something experienced by those who are labeled “addicts” or “dependent” is that a sizable minority of those who at one point meet the criteria for substance use disorder actually do return to moderate or low-risk usage patterns, while others sustain sobriety long enough that they would not be diagnosed with a substance use disorder if they walked into a clinic and took a standard drug usage screening or underwent assays to test for the presence of substances in their body. Yet, many of these same people will insist they are addicts who can never touch a substance or indulge in a behavioral compulsion again without spiraling into a life-ruining bender, which may be completely true, but cannot be known before it happens. This problem in inductive reasoning has been articulated by the Grue Paradox. We presently can’t infer from monitoring someone’s brain, including their dopamine pathways, whether or not a relapse would become a bender or result in moderated usage. Tanha sidesteps this entire problem by rejecting the need to add a label to someone’s cravings.
There have been attempts to incorporate these Eastern ideas of impermanence and radical acceptance within the framework of a permanent self. “Urge surfing,” which was pioneered by Dr. Alan Marlatt as an explicit injection of Buddhist thought into cognitive therapies, has become a standard part of the Dialectical-Behavioral Therapy toolkit that advocates for mindful observation of urges and feelings. Although, as is the case of many “Eastern” concepts being adopted into Western therapeutical modalities, the goal of a global overhaul of one’s existential relation to the reality of identity is set aside in favor of a box of immediate coping mechanisms to break open in case of emergency. The impermanence is applied only to the urges and cravings to use substances or act on intense emotions, which selectively encourages the identification of thoughts and feelings as temporary conditions rather than a recognition that identity itself is existentially impermanent.