greatly boost the desire for more, but after a great many indulgences, the pleasure is ...... opioid detoxification for drug misuse: Summary of NICE guidance.
©American Psychological Association, 2017. This paper is not the copy of record and may not exactly replicate the authoritative document published in the APA journal. Please do not copy or cite without author's permission. The final article is available, upon publication, at: http://dx.doi.org/10.1037/mot0000069
Addiction: Motivation, Action Control, and Habits of Pleasure
Roy F. Baumeister University of Queensland & The Florida State University Amber Cazzell Nadal, Brigham Young University
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Abstract
Addiction is a promising phenomenon for gaining insight into how motivation (wanting and liking) interacts with control of behavior. Some have proposed that addiction primarily undermines action control, such as by weakening free will or overwhelming its capabilities with strong desires. As that view is at odds with empirical evidence, we develop an alternative account. Addiction begins with discovery of new pleasure (liking), which leads to and reinforces patterns of wanting to indulge again so as to recreate that pleasure. Regular use also establishes habits of using, which are sustained by automatization as well as pleasure. Volitional control (a.k.a. free will) remains intact but its limited resources are taxed when the addict tries to quit, so that it is necessary to override many desires to indulge and to counteract the behavioral habits of indulging. Occasional lapses rekindle the habits and desires, thereby increasing the odds of full relapse. These changes to liking, wanting, and doing create many pitfalls for someone trying to quit. It is the combination of frequent weak desires and habitual impulses, rather than irresistible cravings, that most often produce failure to quit.
Key words: motivation, addiction, free will, self-control, habit
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Addiction is one of the most fascinating and problematic forms of human motivation. People become attached to various forms of consumption and activity, sometimes with costly results. Addiction has been known to cause damage to health and longevity, to subvert and destroy close relationships, to produce ruinous money problems, to embroil addicts in legal problems including prison, and to derail promising careers. Impaired judgment and distorted priorities lead to many secondary problems, such as neglect of other important considerations, ranging from traffic safety to caring for one’s children. As we write this, recent news reports have included several separate incidents in which people were found in parked cars, passed out from heroin overdose, while their small children cried forlornly in the back seat. Explaining what motivates people to pursue addiction at such cost to life’s presumably most important concerns is a profound challenge to motivation theory, and the easy explanation that “They cannot stop themselves” raises more questions than it answers. To be sure, not all addictions are so profoundly threatening. Caffeine addiction is widespread but socially tolerated; even ostensibly “drug-free workplaces” often include a coffee pot to enable caffeine addicts to get their fix, and for most people the risks of caffeine addiction are nothing more than the occasional headache, a withdrawal symptom that occurs when caffeine is unavailable. This manuscript reviews empirical findings to evaluate several theoretical perspectives on addiction. As a form of motivated behavior, addiction can affect liking, wanting, and doing — any or all of the above. Addiction promises to offer useful insights into one of the fundamental problems of motivation theory, namely the relationship between motivation and action control. Whether addiction is primarily a change in motivation or volition has been the subject of spirited
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debate. We shall propose that a full account of addiction must encompass its effects on both motivation and action — but perhaps not in the ways most commonly assumed today. We shall propose that addiction is a kind of habit of pleasure. It does not destroy a person’s free will, but it does create both a pattern of desire and a pattern of automatic behavioral response that can place wearing demands on the individual’s capacity for decision-making and self-control. We will first consider some of the standard ways of thinking about addiction, both in terms of the changing definition of the term and in terms of prevailing theories (among both laypersons and professionals). In particular, many consider addiction to consist of a brain disease that undermines free will, possibly by means of overwhelming urges. Then we review evidence that in our view renders those views dubious and perhaps wholly untenable. Following that, we will offer a new integration. The organizing theme is that both motivation and action control processes are affected in addiction, but different theories place different emphases on desire and behavior. We shall attempt to chart a middle way that makes use of insights and evidence from all quarters. An influential article by Köpetz, Lejuez, Wiers, and Kruglanski (2013) argued persuasively that addiction theorists could have much to learn from basic motivation research. We agree and add, vice versa. This manuscript is in the spirit of analyzing addiction in basic motivational terms, in order to inform both bodies of theory. Defining Terms We recognize that key terms have been understood in different ways, and so it is imperative to explain how we use them. By motivation we understand a state of wanting. It may be conscious or unconscious, though we emphasize conscious desires. We also follow
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Baumeister (2016) in distinguishing drives from impulses. A drive is a general, chronic pattern of wanting something, whereas an impulse is a specific instance of wanting to perform a particular action (or have a particular feeling) on a particular occasion. For example, a cigarette addict has an acquired drive to smoke tobacco, though the person does not have this desire constantly. The drive leads to frequent impulses to have a cigarette now. The term addiction has changed its meaning over time. Its original meaning involved merely liking something a great deal, and wanting it passionately. Orford (2001) noted that initially addiction meant being attached to something but more recently it has come to mean conflict about attachment, perhaps especially something of which society disapproves. For a while, addiction was defined in terms of tolerance and withdrawal, but those are no longer viewed as criteria of addiction, and current definitions tend to focus on things like continuing to use the substance or engage in the activity even despite wanting to stop (hence the conflict mentioned by Orford) (Royal Society of Canada, 1989). Modern definitions of addiction also grapple with whether to include so-called behavioral addictions that do not revolve around consuming a mind-altering substance. Gambling, pornography, internet gaming, and similar patterns have been described as addictions, though only gambling addiction has been officially classified as an addiction according to the Diagnostic and Statistical Manual (DSM-V; see Piquet-Pessoa, Ferreira, Melca, & Fontenelle, 2014). Our analysis does encompass behavioral addictions while being open to the possibility that there may be some important differences between addiction to substance consumption and to non-consuming activities.
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It is also likely that not all addictions are the same, and so no one psychological theory will be able to explain them all. Kennett, Matthews, and Snoek (2013) concluded from qualitative interviews that there are at least three distinct categories of addiction, and they differed as to the role (and even presence) of pleasure. We can offer an integrative theory that would fit the main lines of evidence and hence be widely applicable but might be useless for some cases and versions of addiction. The word volition refers to control over behavior based on conscious, deliberate choice. (It is etymologically related to the word voluntary.) It is a flashpoint for addiction theory because of views that addicts perform behaviors they wish they had not done and perhaps cannot avoid performing. Recovering addicts seek voluntary control in order to abstain from indulging. Habits and other automatic responses may subvert volition. Motivation and Action Control The relationship between motivation and behavior control is roughly that between wanting and doing. We assume that these are conceptually and physiologically separate, including separate brain regions: The ventral tegmental area (VTA) and nucleus accumbens (NAc) are associated with reward and aversion, while activity in the motor cortex is associated with voluntary actions. In behavioral terms, motivation initiates tendencies toward behavior, but the person retains the ability to decide whether to act on those desires or not. The problem of addiction can thus be localized in at least two different places: an increase in motivation to indulge, and an impairment in the volitional capacity to control behavior (and in particular to refuse to act on the impulse to indulge).
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The brain gathers incoming sensory information and then uses it to guide action. But that way of describing the action omits the crucial role of motivation. All the information in the world is useless for guiding action unless one knows what one wants and needs. It is generally assumed that the origins of the central nervous system are associated with digestion and locomotion. In plain terms, brains evolved to help animals move around to get food. For that to work, however, the animal has to want the food, so it knows what it is searching for. The basic relationship between motivation and volition is thus that the motivation system sends a signal to the behavior control system to execute a particular action (e.g., finding and eating food). To be sure, motivation is not sufficient for action and may not even be necessary for it, but is often a crucial part of the causal chain that produces behavior. To be sure, the animal does not simply execute whatever impulse arises from the motivation system. It can refrain from enacting it — although that is usually because a second motivational system urges restraint. That brings up the issue of motivational conflict, when a person wants incompatible things or holds incompatible goals. Self-regulation is a vital part of the volitional system that is well suited for adjudicating motivational conflict (Baumeister & Vohs, 2007). Motivational conflict may be especially relevant to addiction. One influential explanation of the conflict was Frankfurt’s (1971) distinction between first and second-order desires: The reluctant addict wants the drug but also wants not to want it. These may all be relevant to addiction. That is, in principle addiction could alter motivation, could directly undermine volition by dictating actions, and/or could impair self-regulation and the ability to resolve motivational conflict optimally. Addiction, Motivation, and Action Control
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Different theories about addiction place differential emphasis on the behaviors as opposed to the underlying motivations. There are two broad forms of volitional theories of addiction. The first form assumes that pleasure plays at most a transient role in the acquisition of addiction, and that addictions are largely a matter of automated, obligatory behaviors. The second form is ironically based in the opposite assumption--that pleasure for a substance or behavior plays so high a role that it effectively overwhelms the volitional system, rendering the individual powerless to resist addictive impulses. We will first turn our attention toward these volitional theories. Loss of Volition: Addiction as Compulsive Behavior We begin with theories that treat addiction as essentially about doing rather than wanting. The general public seems to understand addiction in that manner. Lang and Rosenberg (2016) showed that people associate addiction more with behavior (especially compulsive behavior) than with motivation, in the sense that an addict is someone who regularly performs the problematic actions rather than merely regularly desiring them. However, this may simply reflect the fact that it is possible to desire things without being addicted to them. Still, their answers align well with the notion that addiction is indicated when people continue to indulge despite saying they wish to stop. In particular, from a simple pragmatic perspective, the problem lies in what the addict does. Addicts who want but resist indulging do not create problems for society. Studies by Vonasch, Clark, Lau, Vohs, and Baumeister (2017) showed that ordinary people associate addiction with loss of free will. People who had ever consumed alcohol on a regular, daily basis had less belief in free will than others — but people who had quit drinking believed more strongly in free will than others. Participants who read a vignette about a woman’s
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reckless driving rated her as having less free will and less responsibility when she was rushing to get psychedelic mushrooms (a drug) than to get gourmet mushrooms for dinner. In another study, identical consumptive behaviors were described, but participants rated them as reflecting less free will when they were aimed at consuming alcohol than meat or chocolate. In another, participants who recalled a personal experience of giving in to temptation or addiction rated their current free will as lower than people who recalled an experience of resisting temptation or addiction. Another study showed that that pattern was mainly found when the consequences of yielding were negative: no such effects were observed when people recalled giving in to temptation without suffering negative consequences later. A final study showed that after being induced to disbelieve in free will, participants rated various activities as more addictive, as compared to participants whose belief in free will was left unchallenged. Thus, laypersons appear to equate addiction with loss of action control. Some expert opinions concur with seeing addiction as loss of free will. In recent years the so-called Brain Disease Model of Addiction has become influential, often to the exclusion of alternative views. Leshner (1997, 1999) articulated the idea that addiction is a disease of the brain. In his account, drug use is initially voluntary, but at some point it becomes involuntary, so the person is powerless to resist. A blog by Volkow (2015) took this analysis a step further and described addiction as a disease of free will. Addicts lose their free will, in her analysis, at least in connection with the addictive activity. The addict thus essentially has no choice and cannot do anything other than indulge in the addictive activity. While the Brain Disease Model was originally constructed in the context of substance dependence, researchers of behavioral addictions borrow this model. Indeed, some theorists cited
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repeated failed attempts at abstinence and feeling out of control when indulging in the behaviors as indicators that the same mechanisms are at play in behavioral addictions and substance addictions (Alavi et al., 2012; Grant, Potenza, Weinstein, & Gorelick, 2010; Potenza, 2006). Therefore, some theorists conceptualize addiction as a loss of free will even in the absence of consuming mind-altering substances. A more extreme form of the theory of addiction as damaged volition is that addiction becomes an automatic pattern of behavior, even without motivation. We have heard claims that addicts continue to use despite deriving zero pleasure therefrom, but we have been unable to find much empirical evidence to back this up. Volkow (2015) reports anecdotally that many addicts have told her they no longer get any pleasure from indulging, but we have been unable to find this in her peer-reviewed publications. More thorough evidence comes from qualitative interview research by Kennett et al. (2013). They sorted their 69 interviewee addicts into three groups. One group cited pleasure as the main reason for using. A second said pleasure had initially attracted them to drug use but had dwindled over time, so it was no longer the main factor. The third group claimed never to have gotten pleasure from using. Kennett et al. (2013) reported that these second and third groups claimed not to know why they were addicted or continued using, so that their own behavior was an opaque mystery to themselves. The loss of pleasure does of course not mean loss of desire, though the two are presumably often related. Kennett et al. (2013) described some interview responses as outright skeptical of the view that addicts use without pleasure. Others, however, said it had become a matter of wanting something but not really liking or enjoying it. If it could be established that some addicts continue to indulge despite neither desire nor pleasure, that would be compelling
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support for the view that addiction is primarily a change in action control and perhaps loss of volition (while also indicating that motivation is largely irrelevant). Similar to Kennett and colleagues (2013), Robinson and Berridge (1993) argued for the differentiation of liking (hedonic enjoyment) and wanting (visceral, nonconscious desire) in explaining addictive behaviors. Their framework, the Incentive Sensitization Theory, argues that hedonic enjoyment is implicated early on in addiction, but it wears off over time, leaving only visceral wanting, and that is what explains the difficulty of abstinence. The report that addicts come to feel using is more a matter of obligation than pleasure is consistent with Volkow’s (2015) blog and Kennett and colleagues’ (2013) second profile of addicts. This theory has been extended to explain behavioral addictions to food and gambling as well (see Robinson, Fischer, Lesser & Maniates, 2015). For instance, problem gamblers report that experiencing a near-miss (e.g. being just one slot-machine image away from the jackpot) was significantly more unpleasant than a full-miss, yet problem gamblers play more after experiencing near-misses than they do after experiencing full-misses (Clark, Lawrence, Astley-Jones & Gray, 2009). Again, the third group in Kennett et al.’s (2013) research is baffling. How does one become addicted without any pleasure ever? This is perhaps especially true for behavioral addictions such as gambling, for one can imagine that certain ingested substances could somehow create addictive attachment without pleasure. Still, the notion of joyless addiction remains a challenge for theory. We do offer one speculative way in which this could happen, namely that some people have lives full of intensely negative feelings, and on that basis they might become addicted to some activity or drug that produced a neutral or numb state. Such individuals could therefore plausibly report getting no pleasure from indulging — yet they would
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get a hedonic boost, insofar as feeling nothing is far more appealing than feeling bad. In any case, further work on the possibility of process of joyless addiction is needed. A systematic and profound version of the theory that addiction mainly affects behavior was advanced by Tiffany (1990, 1999). In his account, addiction means that the person comes to indulge automatically, without cravings or other signs of motivation. Tiffany (1990) noted the phenomenon of absentminded relapse, as when addicts who have previously and successfully quit later resume using without intending to do so and without even realizing they are doing so until it is already happening, as evidence that this can happen. We agree that it can, in the form of what Wood and Neal (2007) call “action slips,” that is, well-learned and ingrained forms of behavior asserting themselves while the person’s conscious mind intended to do otherwise but was distracted. One returns to a place where one has often smoked, drunk, played, or otherwise used, assuming that one will not indulge in that manner because one has quit — but caught up in the conversation or other events, one simply resumes. The situational cues activate the behavior sequence of indulging, and this occurs with neither conscious decision nor craving. Our view, however, is that these are exceptions. Conscious decisions and processes can cause behavior, including by overriding habits and other automatic responses (for review, see Baumeister, Masicampo, & Vohs, 2011). Ex-addicts sometimes succumb to using when habitual or automatic processes lead to using while the conscious mind is otherwise engaged — but that does not mean that the person would be unable to refrain if he or she consciously tried. In contrast, the second category of volitional theories invokes motivation: Addiction means that desires and cravings are so powerful that the volition system loses its ability to do otherwise. That is, the first order desires are so strong, that they overwhelm an individual’s
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ability to attend to second-order motivations. This is a popular view in many quarters, including among addicts themselves, and among some treatment providers, especially paid ones (Russell, Davies, & Hunter, 2011). To be sure, the addicts’ and paid health care providers’ opinions are suspect, as they benefit from treating addiction as a disease that renders them incapable of making choices, so that the addicts are exempt from responsibility for their choices to indulge, and they need to purchase expert care. Some evidence for this perspective comes from the Aberrant Learning Theory of addiction (Torregrossa, Corlett & Taylor, 2011). In this view, addictions may be developed and maintained in spite of aversive consequences because drugs alter learning and reward systems of the brain such that positive memories and learning about the substance are enhanced, while negative memories and learning about the substance are diminished. Evidence of aberrant learning extends beyond substance addictions. A review of neurobiological research on behavioral addictions found that problem gamblers and individuals with internet gaming disorder had enhanced reactivity to gaming and gambling cues, decreased loss sensitivity, and increased sensitivity to wins, relative to healthy controls (Fauth-Bühler & Mann, 2017). Thus, perhaps, some gamblers learn to derive high satisfaction from winning while not being much bothered by losing. Gilovich (1983) also showed that gamblers tend to reinterpret some close-call losses as near wins, so in their minds they have many more successes than failures. Such mechanisms would increase the desire to continue and undermine the desire to abstain, possibly explaining the overwhelming nature of first-order desires in spite of negative costs incurred by the addiction.
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In our view, the best evidence for the loss of volition hypothesis is the perseverance of addiction despite explicit wishes to quit. The data on smoking, in particular, uniformly indicate that many people fail to quit, often repeatedly. Volpp et al. (2009) reported findings that each year about 70% of smokers say they would like to quit but each year only 2 to 3% succeed at permanent quitting. A report by the Royal Society of Canada (1989) had a litany of similarly dismal statistics from various sources. Two out of five current smokers had tried (and failed) to quit during the past year. Among people who tried to quit during the past year, half had already failed by the time of survey. Most current smokers have tried to quit at some point. Among people who successfully complete a smoking treatment program (and thus quit), 75-80% can be expected to resume full smoking within a year. Glautier (2004) reviewed various evidence that about half of smokers diagnosed with lung cancer continue smoking, and even about half who survive lung cancer surgery resume smoking. Smoking is widely recognized as causing lung cancer, and so these cases suggest that people are unable (or unwilling) quit smoking even when it has brought them a potentially fatal illness. Smoking may be an extreme, but presumably other addictions would also show discrepancies between how many want to quit and how many quit. Taken at face value, the discrepancy between wanting to quit and quitting seems a strong sign that volition has been hijacked. Addicts claim to be unable to do what they want to do, namely abstain. On closer inspection, however, that evidence is far more equivocal. People may say they want to quit one day but on another day they may change their mind. Loewenstein’s (2005) notion of the hot-cold empathy gap is relevant: When not wanting the drug, they might express the wish never to take it again, but when feeling the motivation and anticipating the pleasure it brings, they might feel quite differently.
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Moreover, abundant evidence indicates that addicted smokers retain free will, as reviewed by Baumeister (2017). For example, smoking shows clear signs of premeditation and planning, voluntary control and use of voluntary muscles, and adjusts to external demands and constraints. Many people do quit and seem always able to refrain from smoking on any particular occasion. Köpetz and colleagues (2013) have pointed out that addictions compete with other motivations for limited ego resources. Thus, addicted individuals may appear to be out-of-control when they use their volitional resources in serving (or fighting) the addiction, leaving diminished self-regulatory capacities to meet the other demands of life. Still, people do quit when they have a compelling reason to do so. All this is consistent with free will and voluntary choice. Integration: Addiction as Motivated Pleasure Habit We pull together the strands from above to propose an integrative model (though again we acknowledge that not all addictions are the same, and so there can be multiple correct yet mutually incompatible theories of addiction). Our model does not include the brain disease model, but it invokes change in motivation as well as the formation of automatic response tendencies. We think most addicts continue to derive pleasure from indulging. Sometimes they have an explicit desire to indulge but other times may indulge because of acquired automatic response tendencies (as put forward by Tiffany, 1990, 1999). Our goal is to elaborate the motivational and behavioral processes (including self-regulation) for the different phases of addiction. Becoming Addicted Addiction begins with the discovery of a source of pleasure and reward. The brain has evolved to furnish feelings of pleasure and satisfaction in connection with doing things that
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improve survival and reproduction. However, the system can be fooled, and some addictive patterns offer shortcuts to feeling the pleasures that were originally associated with major improvements in prospects for survival and reproduction. Cocaine offers some people the kind of pleasure that was typically associated with triumphs in achievement and sexual conquest. Video games offer young men feelings akin to defeating enemies on the battlefield, so as to make one a prestigious and attractive mate and to protect wife and children from predatory enemies. Gambling offers the thrill of danger (of losing money) and, sometimes at least, the satisfaction of acquiring resources. Pleasure rewards and reinforces the actions that produce it. With incipient addiction, smoking, drinking, playing, or using are behavior sequences that gradually become automatic to some degree. This is habit formation. One acquires the habit of having cocktails every day after work, or perhaps starting at lunch or even sneaking a drink at 10 am. That time or occasion cues the habit. In a similar vein, people may acquire the habit of smoking on particular occasions, such as during breaks at work, or before and after meals. The discovery of the new source of pleasure reinforces the wanting response, consistent with the pattern that Vohs and Baumeister (2008) dubbed getting begets wanting. Each successful indulgence reinforces wanting, so that instead of simply returning to baseline after satiation wears off, the drive becomes slightly stronger and/or more frequent. As the person repeatedly indulges the behavior and enjoys the resulting pleasure, desires to indulge increase. Insofar as addiction involves craving, the increase in desire (indeed from initially zero to a high level of frequency and intensity) must be explained. The idea that getting increases wanting offers one way to explain this increase in desire, based on reinforcement.
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Obviously, desires do not continue to increase indefinitely, or else people who discover reliable pleasures would end up obsessed with constant, overwhelmingly strong urges. It is possible that there are limits to how strong motivation can get. It is also possible that the reinforcement value of indulging is reduced with frequent enjoyment: The first few times might greatly boost the desire for more, but after a great many indulgences, the pleasure is familiar and operates merely to sustain the desire than increase it further. Tolerance (see next section) could reflect this pattern. This process of gradually increasing motivation through repeated indulgence leading to pleasure indicates the operation of basic learning principles and processes (see Glautier, 2004). Addiction does not subvert these but rather relies on them. The brain periodically has desires for a familiar pleasure and has automatic responses to cues that activate them. As long as the addict can indulge without problems, these are not stable but rather enter a spiral of more indulging leading to more reward, followed by more indulging. Increasing automaticity is one of the basic features of the brain, which presumably envolved to make successful, valued behaviors easier to execute. The process by which getting begets wanting may also involve increasing external cues for indulgence. The racetrack gambler may subscribe to periodicals that offer information about contestants in upcoming races, and these periodicals also serve as cues to bet. The coffee addict may purchase cups and fancy machines to facilitate drinking — and these then serve as reminders of the appeal of coffee. What, then, sets those who continue to indulge in addictive substances and behaviors apart from those who use only casually or infrequently? Almost certainly, there are neural
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(Koob & Volkow, 2010) and epigenetic (Tsankova, Renthal, Kumar & Nestler, 2007) factors at play. These may make some individuals enjoy particular kinds of pleasure more than others, thereby helping them become attached to indulging. Another possibility is that the indulgence satisfies multiple drives. For instance, an individual whose friends smoke may be more likely to continue smoking if doing so results in both hedonic pleasure and improved feelings of belonging, as compared to someone for whom smoking brought only hedonic pleasure or social connection. Consistent with this idea, Fidler and West (2009) found that smokers’ level of dependence was correlated with the number of motives they reported, and only about 4% of their sample reported having no motives for smoking. Likewise, rats are more likely to become addicted to morphine in bare environments, where there may be more reasons to indulge (e.g. boredom becomes and additional motive, which is a common reason for substance use among humans as well), than they are in environments where more entertainment and socializing needs are met (Alexander et al., 1980). Similar studies have shown that rats are more likely to seek ethanol in environments that offer no alternative sources of rewards (Pyszczynski & Shahan, 2011). Thus, addiction may be most likely when the person is susceptible to a particular kind of enjoyment and the environment offers them relatively few alternatives. Tolerance Tolerance may also fuel an initial upward spiral in use, though it obviously tends to plateau as well. With regular use at the same dose or level, the body adapts so that the yield of pleasure declines. This again appears to be a natural process, like desensitization to negative experiences and like opponent-process development (Solomon & Corbit, 1974). Alcohol is well known to be associated with increasing tolerance, so that a given dose of alcohol will produce
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less intoxication among regular users and heavy drinkers than among novices or light drinkers. Again, though, hardly anyone seems to show an endless linear increase in alcohol consumption, and so the drinker increases consumption during the initial stage but may then reach a plateau. Whether tolerance increases in connection with behavioral addictions is debated. Grant, and colleagues (2010) reviewed evidence from a variety of behavioral addictions, including pathological gambling, compulsive sexuality, compulsive shopping, and kleptomania. They concluded that many people with such behavioral addiction syndromes report that repeatedly performing these actions leads to a gradual decline in the amount of pleasure or satisfaction obtained, and/or the need to increase the intensity of the behavior in order to garner the same desired level of pleasure. That is broadly consistent with an increase in tolerance. Some researchers have challenged the validity of tolerance findings in behavioral addictions. Blaszcynski, Walker, Sharpe, and Nower (2008), concluded that while gambling addicts do appear to increase the amount they bet over time, this process reflects increasing confidence of winning, more than a development of tolerance so that bigger bets are needed to furnish the same level of pleasure. In pure games of chance, however, the odds of winning do not increase based on skill or learning, so increased confidence is irrational and may be a rationalization for wanting to bet more. There is also some psychophysiological evidence of tolerance. Griffiths (1993) found that drops in heart rate following game play occurred among frequent gamblers, but not among infrequent gamblers. All these findings suggest that some forms of increasing tolerance may apply in behavioral as well as substance addictions, thereby contributing to escalating indulgence. Maintenance Phase
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Conscious volition in the form of free will is not abrogated by addiction (see Baumeister, 2017). However, the habit of addictive indulgence becomes the default option. Addicts will indulge unless they exert self-regulatory effort to override the habit. The addict will feel frequent impulses to indulge and will yield to some of these. These indulgences may be motivated by the desire for the activity — or they may arise simply because cues activate the habit. For example, alcoholics may sometimes feel a serious desire to have a drink (or several), but at other times they will have one simply because they have formed the habit of having one after work. During the maintenance phase of addiction, therefore, the addict indulges regularly and generally enjoys the results. Volition, including self-regulation and free will, is used to sustain the addiction. A systematic formulation of this idea was put forward by Baumeister and Vonasch (2015). They noted that most theories emphasize that self-regulation is mainly used to resist addiction, but this may miss important aspects. Building on work by Rawn and Vohs (2011), they pointed out that initially self-regulation is sometimes exerted to promote using the substance. Most people do not enjoy their first cigarette or beer, so they self-regulate to make themselves do it, such as to comply with social norms among their peers, or to push through an unpleasant initial step of ingesting the drug in the hope of discovering the pleasure afterward. In the phase in which the person is addicted but is not trying to quit, self-regulation is used to indulge and also to ensure that indulgence does not interfere with life activities. One can smoke or gamble or even use heroin for years — as long as one complies with societal rules and demands, so that the addiction does not interfere with the other requirements of adult life. In this account, addiction is essentially a habit of pleasure. The addict has discovered a way to feel good and developed habitual ways of making that happen. On a given evening, it is
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rational to feel really good rather than just so-so, and therefore it makes sense to smoke, drink, play, or otherwise indulge. As weeks and months go by, this continues to be the default behavior pattern. In terms of action control, addictive indulgence is sustained partly by force of habit, including the behavior sequences activated by external cues. Habits are initiated automatically, but volition may have to cooperate. For example, smokers must comply with myriad restrictions and regulations in order to smoke. Wherever possible, automatic behavior sequences sustain the addiction (e.g., Tiffany, 1990, 1999). Volition merely goes along and helps as necessary. Addictions may become foundational habits around which other habits revolve. This may be partly due to symptoms of withdrawal. Caffeine addicts may develop the habit of having coffee before work so that they do not develop headaches. Smokers get in the habit of spending work breaks by going outside where smoking is permitted. The elicitation of addiction-relevant goals (i.e. getting a fix) primes the habits that have been successful in leading to indulgence in the past. For instance, women with a history of exchanging sex for cocaine have shown greater approach tendencies toward sex trades when primed with cocaine-relevant words, relative to neutral words (see Köpetz et al., 2013). As these secondary habits become automated, they fill the addict’s environment in with addiction-related cues. The smoker must keep an ashtray on the table, but that ashtray also cues the smoker to smoke. The smoker makes friends with other smokers outside during their breaks at work, and those friends cue smoking as well. Thus addictions and the habits that serve them become positive contextual feedback loops. The construction of these secondary habits organizes the addict’s life around cues for the substance or behavior. Moreover, when the addict derives pleasure from these secondary sources (i.e. when
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the addict derives pleasure from friendships made on smoke breaks), it makes the addiction all the more difficult to extinguish (Pyszczynski & Shahan, 2011). Thus, the addict in the maintenance phase works out how to continue indulging (and to prevent it from interfering too much with other aspects of life). There is a reciprocal relationship between facilitating cues and indulgence: The more one indulges, the more one adjusts one’s environment to facilitate indulgence — and then, conversely, the more that environment promotes indulgence. Trying to Quit Thus, motivation and volition can sustain the addiction during the maintenance phase, possibly without much difficulty. The difficulties begin if the addict tries to quit. As already noted, addicts typically believe that if they were to abstain, their cravings would become stronger and stronger, to the point at which they would become overwhelming — but this is mistaken. Sayette, Loewenstein, Kirchner, and Travis (2005) showed that such predictions of rising cravings were false, and actual cravings merely fluctuated somewhat randomly. Moreover, Shiffman et al. (1997) showed that after smokers resolved to quit, their desires were generally substantially weaker than prior to quitting. Why then is it so hard to quit? There are multiple processes that sustain addiction, and any of them can undermine the quitting process. We are proposing that both motivation and action control change during addiction. That creates multiple pitfalls for the would-be ex-addict. First, the habit of addictive indulgence automatically creates behavioral tendencies and situated impulses to indulge. Once the habit of addictive indulgence is established (possibly in connection with particular environmental cues, such as time and place, or friends or
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paraphernalia), the default plan is to indulge. The habit will produce frequent impulses, such as activated by external cues. Times, places, occasions, people, and other cues can evoke the feeling that now would be an appropriate time for a cigarette, a drink, or a game. To be sure, these habitual impulses are weak and can be easily resisted. Still, indulging is the default. Resisting takes self-regulatory effort. We have assumed that the person likes indulging, which is why he or she became addicted in the first place. The habit of indulging, evoked by external cues, makes the person think of indulging and, crucially, reminds the addict of the possible pleasure. To continue resisting is to forego the pleasure that one anticipates. Even if the addict is not feeling a craving for that pleasure, he or she may feel a sense of deprivation or loss upon deciding not to pursue it. Thus, the addict may be able to resist these weak impulses, but to do so is doubly costly. First, resistance takes self-regulatory effort and depletes resources (e.g., Baumeister, 2003; Baumeister & Vohs, 2016). Second, to resist is to lose out on the pleasure that could be had by indulging. Another pitfall involves the motivation to use. Addiction means acquiring the desire for the pleasure of indulgence. Motivation in the form of subjective desire involves wanting to indulge. The cravings may become weaker and less frequent after one quits, but they are nonetheless real. As already noted, a person’s capacity for self-regulation and thus for resisting urges — a person’s free will, so to speak — is variable rather than constant (e.g., Baumeister, 2003; Baumeister & Monroe, 2014; Baumeister & Vohs, 2016). The volitional capabilities to guide behavior based on rational long-term calculations rather than by short-term impulse fluctuates.
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Ego depletion, which may be caused by stress or other demands, will create moments of weakness, and the person gives in to desire. The effects of ego depletion may not even depend on feeling a desire, resistible or irresistible. Neal, Wood, and Drolet (2013) showed that habitual responses are all the more frequent and likely during ego depletion. This fits the view of effortful self-regulation as top-down control to intervene in and override automatic responses. When the top-down control is weak, automatic responses become increasingly common. The situation of the ex-addict is to have a stream of impulses to indulge. These may vary in motivational strength. Let us assume that the impulse to indulge fluctuates randomly and the self-regulatory resources to resist also fluctuate based on external demands, which are mostly random with respect to whether one indulges. Over time, there is a high probability that some moment will arise when self-regulatory resources are low and urge (desire or habit activation) is high. Surely, thinks the addict, he or she could have just one drink or cigarette. Thus, the addict trying to quit must resist impulses to seek pleasure or merely to follow habitual, established behavior patterns. Resisting requires the expenditure of self-regulatory resources — and there are many other demands on those resources, so their availability to resist the impulse to lapse is unstable. Still, quitting is possible, and quite regular. In fact, the majority of smokers (Chapman & MacKenzie, 2010) and problem gamblers (Slutske et al., 2003) quit without professional help. Withdrawal The process of terminating an addiction is made worse, sometimes considerably worse, by withdrawal symptoms. These are tangential to the present analysis, though some addicts may
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be motivated to sustain their addiction so as not to suffer withdrawal. For a time, addiction was understood as being sustained by fear of withdrawal, and this helped fuel the impression that addicts might continue using without getting any pleasure from indulging or even wanting the experience. However, this view has largely been discredited, chiefly based on evidence that many addicts suffer through withdrawal, get over it, abstain for a while, and then relapse (see Ainslie, 2001). If fear of withdrawal were the key factor, no one would resume addiction after getting past the withdrawal. Withdrawal phases vary among substances, and indeed “cold turkey” withdrawal from alcohol is sometimes fatal. Heroin withdrawal has been compared to a very bad cold or flu (e.g., De Ropp, 1976). Cigarette withdrawal patterns differ among individuals (e.g., Piasecki et al., 2000, 2003), but most symptoms are gone after about a month (Hughes, 1992). Evidence for withdrawal from behavioral addictions is mixed. Grant et al. (2010) noted that although withdrawal from behavioral addiction does not produce serious bodily problems such as medically dangerous reactions, there are many reports of bad moods and other aversive psychological symptoms during that process. The DSM-V lists restlessness and irritability during abstinence as diagnostic criteria for pathological gambling. Researchers have also shown that anger, guilt, disappointment, depression, anxiety, and headaches are common among abstaining pathological gamblers (Blaszczinsky et al., 2008; Cunningham-Williams et al., 2009). Moreover, the intensity and degree of these withdrawal symptoms are on par with those experienced by alcoholics (Blaszczinsky et al., 2008). Other aspects of withdrawal from substance addiction may be lacking with behavioral addictions, to be sure. It is unlikely, of course, that withdrawal symptoms for behavioral addictions can be fatal, as is the case for alcohol withdrawal.
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Still, it is hardly controversial to suggest that withdrawal exacerbates the problems of quitting. First, it creates some aversive states, for which the obvious cure would be to indulge. Second, efforts to cope with the negative states (such as by not being grumpy to co-workers and loved ones) will further deplete self-regulatory resources, thereby reducing the capacity to resist impulses to lapse. Lapse and Relapse Various studies indicate that lapse leads to relapse, although this is hardly a deterministic sequence such as would be asserted by the perspectives advocating loss of volition and loss of free will (see Baumeister, 2017). By way of definition, lapse refers to a single indulgence by an ex-addict, whereas relapse signifies return to regular use, usually at the same level as prior to the quit attempt. A lapse is thus a partial, momentary failure, whereas relapse is a definitive, lasting failure of quitting. Working with a sample of cigarette smokers, Gwaltney, Shiffman, Balabenis, and Paty (2005) found that there were on average 29 lapses before full-blown relapse. That figure may be lower for other addictions, because cigarette smoking consists of such brief indulgences. We doubt, for example, that heroin users normally record 29 lapses before full relapse. Some addicts (including many in Alcoholic Anonymous) espouse the view that a single lapse will lead inevitably to intense binge and relapse, but it is possible that that view is simply a strategic doctrine to discourage people from thinking that they can safely indulge now and then. A remarkable experimental study by Shadel et al. (2011) used a sample of smokers who quit smoking. A few days after they quit, they came to the laboratory, and by random assignment half of them were assigned to smoke one cigarette. This experimentally mandated lapse doubled the
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rate of relapse, though again it did not guarantee it. The study is important because correlational studies linking lapse to relapse are confounded, insofar as both lapse and relapse could stem from the same underlying causes, such as strong desires or weak self-control or simple disinclination to sustain quitting. The experimental manipulation and findings by Shadel et al. (2011) establish that lapse causes relapse, though in a probabilistic rather than deterministic manner. Putting all this together can begin to suggest why addicts relapse. Habits of use continue to be present in the mind after quitting, ready to initiate the familiar action of using. Moreover, the liking for the pleasure of using and the desire for that pleasure also remain. Both habit and desire create urges to resume using. Either process can subvert abstinence, at least insofar as producing a lapse. These continue operating when one quits. Withdrawal creates additional unpleasant feelings that could be solved by indulging. Urges to indulge may diminish in strength and frequency, though occasional strong ones are still felt. Moreover, the urges were pleasant during regular use but become unpleasant after one quits (Sayette et al., 2005), thereby adding to the negative feelings and enhancing the appeal of indulging again so as to feel better. The frequent need to resist urges depletes willpower, which takes a toll on other aspects of life Willpower fluctuates, and so the capacity to resist may happen to be low coinciding with high urge, making lapse more likely. Each lapse reminds the brain of how pleasant the addictive indulgence was. Once lapses begin, the likelihood of full relapse is significantly increased. Further Implications of Habit We have likened quitting addiction to breaking a bad habit. Wood and Neal (2007) note that habits are never really erased, however, because that would require a kind of unlearning. Rather, people merely establish new habits that compete with the old ones. The point is that the
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old habits remain there in the mind, ready to reassert themselves. Applied to addiction, this means that addicts would forever be more susceptible to becoming addicted again than would someone who has never used (or never had that addiction). This point echoes the AA doctrine that alcoholism is a lifetime affliction and relapse remains a threat even after many years of abstinence. Köpetz et al. (2013) have noted that the principle of getting begets wanting (Vohs & Baumeister, 2008) cannot account for relapses after extended periods of abstinence. However, in keeping with AA doctrine, lapses may remind the brain of pleasures that are derived from habitual indulgences of the past, and hence they increase the likelihood of full-blown relapses. The habit pattern, in combination with tolerance, can also explain the phenomenon of overdose upon relapse. During the maintenance phase of addiction, a regular drinker or heroin user has presumably reached a fairly stable habit involving the optimal, regular dose. For example, Flanagan’s (2011) first-person account of his alcohol addiction describes how he struggled to keep his consumption within his target range, such as 15 to 23 beers per day, or 9 to 12 bottles of wine. At some point the person manages to quit and stays clean for months. Then something bad happens such as a romantic breakup or work setback, and the addict permits him or herself to have a lapse as a way of coping. Preoccupied with the unhappy recent events and eager for the pleasures of indulging, the addict simply follows the familiar habit of how much to use — not adjusting for the fact that his or her tolerance has diminished sharply over the intervening months. Researchers have documented the increased mortality risk among alcoholics and heroin users who lapse following detoxification (Pilling, Strang & Gerada, 2007), and have found that detoxified individuals were the most likely to fatally overdose (Strang et al., 2003).
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One reason cigarette addiction may be so hard to break is the sheer number of impulses. Hall and Havassy (1986) found that smokers rated abstinence as more difficult to sustain than heroin users. It is possible that the reason for this lies entirely in the psychopharmacological processes associated with the different chemicals, such that heroin is somehow less addictive than nicotine. Alternatively, the reason may lie in the process of habit formation via reinforcement. To be sure, the reward value of a cigarette is reportedly much, much less than the reward value of a dose of heroin, in the sense that a cigarette produces at best brief, mild pleasure, whereas people often describe at least their first heroin doses as the most intense pleasures they have ever experienced (and each dose lasts for many hours). But the very duration of the heroin experience sharply reduces the number of learning trials. Put another way, a two-pack-a-day smoker will light up forty times per day, with each one producing some reward and thereby reinforcing the habit. In contrast, a heroin user will inject at most once in a day and be set up for perhaps 10-12 hours, and when it finally wears off there is likely to be a break of many hours or even days before the next dose. The cigarette habit thus gets rehearsed nearly fifteen thousand times per year — far more than the heroin habit. An additional aspect is that the many cigarettes smoked each day establish associations to many different situations and cues that can subsequently activate another impulse to smoke, whereas again the heroin user forms far fewer such associations. All of this could make the habit much more ingrained among smokers than heroin users. Alcoholics, gamblers, and other addicts presumably fall somewhere in between. Most theorizing about addiction focuses on the impact of the chemical, but the drug delivery process could play a role as well. Recent experimental studies have confirmed that
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rituals can enhance pleasure. Vohs, Wang, Gino, and Norton (2013) showed that arbitrarily concocted (by the experimenters) rituals increased participants’ enjoyment of various pleasures such as eating chocolate and even carrots and lemonade. Moreover, the effect of the ritual was mediated by increases in the person’s interest and involvement in the experience. Applied to addiction, consumptive activities that require behavioral sequences may gain in addictive potential, as compared to other indulgences that do not involve much ritual. Some drugs, for example, are consumed simply by taking a pill, whereas others require complex, ongoing action sequences (as in free-basing cocaine use). Although obviously taking pills can become addictive too, presumably without much ritual, the drugs that do ritualize consumption may get extra power from that process. The power of reinforced ritual may help shed light on behavioral addictions, in which there is no ingestion of mind-altering chemicals. Gambling is perhaps a prime example. Caricatures of gambling often include such rituals as chanting lucky numbers, wearing a lucky article of clothing, or blowing on dice. Indeed, multiple studies have found that problem gamblers were more likely than other gamblers to endorse use of such rituals while gambling (Joukhador, Blaszczinsky & Maccallum, 2004; Ohtsuka & Chan, 2010). Along similar lines, Toneatto (1999) observed that problem gamblers bet more frequently and bet larger amounts when they threw the dice than when someone else did. Some of this may reflect an illusion of control, such that the person irrationally believes handling the dice oneself will produce a better outcome than letting someone else do it. But it could also indicate greater personal involvement in the ritualized behavior aspect of gambling. Conclusion
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We have analyzed the interplay between motivation and action in addiction. Both action control processes and motivational processes change, and in related ways. Both sets of changes tend to push to sustain the addiction and militate against quitting. The popular stereotype of addiction (most recently formulated in the brain disease model) seems to be that the person acquires overwhelmingly powerful desires and cravings (thus new motivation) while weakening free will and other forms of behavioral control, so that volition is reduced to slavishly enacting the promptings of the addictive desires. In that view, the person is unable to do anything but perform the behaviors associated with the addiction, such as obtaining drugs and ingesting them. Attempts to break off the addictive pattern supposedly cause cravings to escalate and intensify, to the point that resistance becomes futile. This model is however not well supported by the evidence — indeed seems sharply contradicted at multiple points. Volition and free will remain intact. Desires and cravings are generally weak. Cravings do not escalate steadily after quitting. Cleary, a new understanding is needed. In place of overwhelmingly strong cravings and diminished free will, we have reconceptualized addiction in terms of weaker (albeit possibly frequent) desires and automatic patterns (habits). Addiction starts with the discovery of a new source of pleasure, and the person wants it again. Repeated desires followed by satisfying experiences instill a chronic motivational pattern, that is, they create a pattern of recurring desires. As the person regularly performs the actions that produce this pleasure, these behavioral sequences become automatized, which is to say indulging becomes a powerful habit. In a feedback loop that can become a vicious circle, indulgence brings pleasure and reinforces the wanting while cementing the habit. One may
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indulge sometimes without desire but still get pleasure, which may then increase the chances of wanting again or of following the habit again. Crucially, the person retains (so-called) free will and conscious control, and so each impulse to use can be resisted. Both the habitual inclination to indulge and the frequent desires for the resulting pleasure can be resisted. But resistance takes effort and depletes self-regulatory resources. While using, it is not that difficult to skip or delay any particular indulgence, but once one resolves to quit, resisting becomes an unpleasant treadmill of saying no to oneself over and over. Moreover, addiction is not simply a state of mind or brain sending forth troublesome impulses. During addiction, indulging gets associated with various cues, especially given the enjoyment of the indulgence. Certain environments become associated with the pleasures of indulgence. Moreover, and quite importantly, addicts probably add to the cues that surround them. For example, smokers buy ashtrays, some of which may have sentimental value, and after quitting, seeing the ashtray may evoke the habit or desire, requiring the person to exercise costly self-control again. Saying no to oneself each time is costly not only in terms of self-regulatory resources (willpower) but also in hedonic terms. Resisting requires not just stifling the urge but also foregoing the pleasure. Even in the absence of craving, a habitual impulse to indulge may be resisted but may remind the person again of the pleasure that is being lost. That process is unpleasant, which enhances the appeal of seeking pleasure. If there are withdrawal symptoms to contend with, then resisting the impulse is essentially choosing to feel bad rather than good, which is a difficult choice to make, especially over and over.
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It may seem that our views are self-contradictory. We have rejected the notion that addiction entails loss of free will and volition — but then we note that addicts trying to quit deplete their self-regulatory resources, which amounts to an impairment of their capacity for volition. Yet the two views are quite different. One important test case would be the addict who is not trying to quit. In our view, such a maintained addiction should not be all that depleting, and the person would retain volition (except for whatever is necessary to maintain use, and this may soon be achieved by well-designed habits). The evidence for cigarette smoking seems quite consistent with this view. Trying to quit smoking may well be depleting and may impair the person’s ability to make good decisions and exert self-control generally, for as long as effort and resources are devoted to the struggle to quit. But the non-quitting smoker is unaffected. Sure enough, many smokers have performed well at highly demanding, responsible jobs and in other roles requiring their full powers of volition. Thus, addiction typically entails a combination of wanting, liking, and doing, each of which contributes to the pull to continue indulging. To stop using may require the person to override habits (doing), to resist urges (wanting), and to forego anticipated pleasures (liking). Certain occasions, such as being under stress, may reduce one’s ability to resist the habit or desire while also increasing the appeal of the now-forbidden pleasure, and so lapses are especially likely at these times. A lapse rekindles the addiction, such as by practicing the habit, reminding the brain of the pleasure, and reinforcing the pattern of wanting, and so lapse promotes relapse. The high relapse rate under such conditions is perhaps tragic but not surprising. Issues for Further Work
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As we noted, the liking aspect of addiction has been debated, and there is at least scattered evidence that some addictions are sustained without much new pleasure. Based on motivation theory, we find it difficult to envision that wanting can be sustained over a long time without liking, but possibly it can. Further work should subject the notion of joyless addiction to careful, open-minded but skeptical and rigorous examination. Reports by addicts themselves are one source of evidence but clearly subject to a variety of self-serving and other biases. One possibility is that an addiction ceases to bring pleasure but is still preferable to the aversive state of the person’s life. When daily life brings stress, anxiety, and other negative feelings, addictive indulgence may be a distraction that is welcome as a relief from the negative even though it brings no actual joy. The general principle that bad is stronger than good (Baumeister, Bratslavsky, Finkenauer, & Vohs, 2001) would suggest that people find it highly appealing to escape a negative state to a neutral one. Put another way, moving from -5 to 0 is even more appealing than moving from 0 to +5. Along these lines, some researchers have suggested that addictive behaviors might be a means of restoring feelings of control, such as cigarette smokers who believe that smoking helps them cope with stress (Bergen, Newby-Clark & Brown, 2014). If we wish to take the idea of joyless addiction more seriously, then emphasis would have to fall on the habit aspect. There should be evidence of people becoming habitually embroiled in neutral and even aversive activities. Some people engage in practices such as cutting their skin, pulling out their hair, or biting their nails, which seem inherently unpleasant. Any parallels between such behavior patterns and addiction (especially behavioral addictions) would be illuminating.
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Concluding Remarks Addiction remains one of the most important and formidable problems — both for society that must cope with the damage caused by addicts to themselves and others, and to researchers who seek to understand why people fall into these traps. Our work was inspired by Köpetz et al.’s (2013) assertion that addiction researchers can learn from basic motivation theory. Building on that, we have proposed that that particular information highway can move in both directions, so that motivation researchers stand to learn a great deal from addiction. Our analysis suggests that addiction can help illuminate how behavior is related to motivation and, indeed, a theory of addiction should recognize the distinct if interrelated effects on wanting, liking, and doing.
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