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Substance Induced Myopia
C H A P T E R
36 Substance Induced Myopia Nora E. Noel, Jennifer A. Heaton, Brian P. Brown University of North Carolina Wilmington, Wilmington, NC, USA
O U T L I N E Definition
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Going Beyond Alcohol: Substance Myopia?
352
Development of the Model
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Limitations of Myopia-Based Explanation
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Behaviors Thought to be Affected by Alcohol Myopia
Conclusions
353
351
Does Alcohol Myopia Explain How Intoxication Can Lead to More Prudent Behavior?
351
DEFINITION Substance Induced Myopia (or Substance Myopia) refers to a model often used to explain the acute effects of a psychoactive substance on a person’s subsequent behavior in a particular situation. The idea is that when taken in a significant dose, the substance interferes with attentional processes and narrows a person’s ability to perceive and comprehend all the stimuli in the environment (hence the term myopia used as an analogy to eye disorders). According to the myopia model, the higher the dose of a substance beyond a critical threshold, the more it interferes with information processing, leading the person to rely on only the most salient cues in the environment to interpret the situation. Generally, the model is referred to as alcohol myopia because the vast majority of the relevant research examines the effects of alcohol on behavior. However, from a hypothetical standpoint, intoxication with any psychoactive substance that limits attention could have a similar effect.
DEVELOPMENT OF THE MODEL The term alcohol myopia was first coined by Claude Steele and Robert Josephs in a 1990 article in Principles of Addiction, Volume 1 http://dx.doi.org/10.1016/B978-0-12-398336-7.00036-X
the American Psychologist. They were searching for an explanation for alcohol’s inconsistent effects on disinhibition as well as a related factor, anxiety reduction. A commonly assumed mechanism for alcohol’s association with risk-taking or engaging in socially unacceptable behavior is that intoxication temporarily interferes with one’s inhibitions that might normally have kept these behaviors in check. The disinhibition hypothesis posits that under normal circumstances one is inhibited by anxiety from breaking social conventions or exposing oneself to danger. Alcohol intoxication is believed to reduce that anxiety, thereby disinhibiting the person’s behavior. Much anecdotal evidence exists that show when people drink, they can become uncharacteristically nasty, unpleasant, aggressive, extroverted, sexual, and so on. As Tara MacDonald and her colleagues put it, common sense flies “out the window” and intoxicated people may engage in many risky behaviors that while sober they would not consider. Such behaviors include driving under the influence of alcohol or drugs, having sex without protection, or starting a fight with a large stranger. However, when tested under controlled conditions, such as in a laboratory, alcohol intoxication does not appear to disinhibit behavior consistently. Often, people do report less anxiety
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Copyright Ó 2013 Elsevier Inc. All rights reserved.
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when they are intoxicated, but sometimes, unpredictably, they do not. In fact, people may become even more depressed or anxious when drinking and, in some investigations, intoxication can be associated with more prudent or altruistic behavior than sobriety. Likewise, a large amount of research on the tensionreducing effects of acute doses of alcohol (see the encyclopedia entry on the tension-reduction hypothesis) previously had shown that drinking alcohol can reduce tension or anxiety, but sometimes it does not. Tension reduction in response to alcohol intoxication is an unreliable and often unpredictable consequence. Moreover, as noted above, sometimes drinking even leads to increased tension, anxiety or depression, much to the disappointment of the person drinking for the purpose of tension reduction. To explain the inconsistent effects of intoxication Steele and Josephs proposed a cognitive mechanism (they called alcohol myopia) which they said predicted alcohol’s effects better than a disinhibition model. They defined alcohol myopia as “a state of shortsightedness in which superficially understood, immediate aspects of experience have a disproportionate influence on behavior and emotion, a state in which we can see the tree, albeit more dimly, but miss the forest altogether.” By way of explanation, an overarching principle of social cognitive research is that people’s responses to a social situation are largely influenced by how they interpret the vast array of stimuli or cues they perceive in the situation. Given the same social situation, a person may make vastly different interpretations depending on the stimuli to which he or she attends. The person’s response is then guided by their interpretation. For example, suppose a man at a party becomes interested in a woman and attempts to strike up a conversation with her. She might react by ignoring him completely or even being hostile. Such a communication would be easy to interpret and he could move on to talk to someone else. On the other hand, if she responds to his overtures with conversation, smiles and laughter at his jokes, the interaction becomes ambiguous. Is she just being polite? Is she interested, but cautious? Is she attracted to him, too? To answer these questions, he must observe her actions and the external situation to make a judgment about how he will respond to her. Obviously, it would be impossible for a person to allocate attention to every stimulus in an environment. Instead, the man focuses on his internal and the external cues in the situation that he deems important (or salient) stimuli and he filters out irrelevant cues. His internal state (he is interested in her) and his history of interacting with women may influence part of this filtering. Note that attentional
filtering is a relatively automatic (non-conscious) ongoing process that happens rapidly (in milliseconds). Quite a bit of cognitive-psychological research demonstrates that even under ordinary circumstances people can miss what should be very obvious stimuli and events if they do not fit with their expectations. For example, inattentional blindness refers to the failure to perceive an event that would be quite noticeable while engaged in an attention-demanding task. The published scientific research is compelling, but the phenomenon is also famously demonstrated by the short video posted on You Tube in which the viewer is asked to count the number of ball passes a basketball team makes. Most viewers watch the team and at the end of the video seem completely unaware that a large man in a bear costume walked right through the center of the action. After the bear is pointed out, he is very obvious on the second viewing. Thus, people are already selectively screening stimuli, often guided by what they expect, or want, to see. If we return to the man at the party, he is busy attending to social cues that could signal that the attractive woman is mutually attracted to him, unaware that he is selectively screening information he will use in his decisional process. He will use his filtered information to decide how to behave with her. According to the alcohol myopia model, if the man is or becomes intoxicated, he will be cognitively impaired, thus having an even more limited capacity to process information. The selection filter becomes tighter, narrower, and he will be capable of attending to only the most salient cues, as determined by his internal state or, perhaps, some extremely obvious cues in the situation. He is more likely to miss other important information. Thus, if sober, he might notice that she is smiling (very evident or salient to him) but also be aware that subtly she is making eye contact with other people and appears to be edging away from him. She is probably not interested in conversing with him. However, if alcohol intoxication narrows his attentional processing (i.e. he experiences alcohol myopia), he is likely to interpret her social cues incorrectly, focusing only on her salient smiling behavior, and assume that she welcomes his company. His subsequent behavior with her might be socially inappropriate and very unwelcome. To further illustrate how the myopic state might function, several researchers suggest that intoxicated men present a higher risk of sexual aggression than sober men because they focus only on their own internal sexual arousal, attending most closely to any positive behaviors exhibited by the woman, while failing to perceive or process any discouraging or negative behavior on her part. The latter cues are
I. THE NATURE OF ADDICTION
DOES ALCOHOL MYOPIA EXPLAIN HOW INTOXICATION CAN LEAD TO MORE PRUDENT BEHAVIOR?
usually less salient because they do not fit with his expectations.
BEHAVIORS THOUGHT TO BE AFFECTED BY ALCOHOL MYOPIA Researchers have conceptualized alcohol myopia as the explanation for a fairly long and varied list of alcoholrelated behavior. Initially, Steele and Josephs used the concept to explain alcohol’s inconsistent effect on anxiety, hypothesizing that in a situation where there are no distracting or more salient stimuli, intoxication may cause people to focus on the obvious, salient anxiety-producing stimuli and become more anxious, rather than less anxious after drinking. Their experiments supported their hypothesis by showing that when intoxicated people focused on an impending anxiety-provoking event, they became more anxious, but, in contrast, when intoxicated participants were given a distracting task, more attention-demanding than the anxiety-provoking event, they became less anxious. Similarly, results of some observational and survey studies suggest that people may drink to escape or relieve depression (e.g. drown their sorrows), only to find themselves more depressed (e.g. crying in my beer) as they become more intoxicated. Thus, proponents of the alcohol myopia model have suggested that merely drinking, without engaging in an attention-grabbing distraction, leads to a focus on the person’s internal state of depression, which then intensifies. Other researchers have hypothesized that alcohol myopia plays a key role in alcohol-related aggression. Laboratory studies support the idea that alcohol consumption may increase aggression because the intoxicated individual focuses on reasons for fighting (e.g. “This person insulted me.” “This person stepped ahead of me in line.” “This person bumped me intentionally.”). Reasons for fighting are often quite salient in a drinking situation such as a loud bar or party. According to the model, the alcohol-myopic person loses awareness of less obvious circumstances, both external (e.g. “That person has friends here.”) and internal (e.g. “I don’t want to fight with someone. I’d rather just have a quiet evening.”) that might normally limit their aggression. He or she then reacts with aggression. In a similar vein, many researchers suggest that alcohol-related sexual aggression increases when cues for the instigation of sexual behavior are more salient than cues inhibiting sex. According to the model, the intoxicated sexually aroused man might believe that he has the right to demand or force sex from his partner, perhaps because he thinks that the she instigated sex. Her sexual cues are salient to him and her protests are not. Moreover, several studies of risky sex, such as having sex with an unknown partner or without a condom,
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support the idea that when both parties are intoxicated they are likely to focus exclusively on their sexual arousal (the salient stimulus) and ignore less salient concerns such as becoming involved with an inappropriate partner, becoming pregnant, or acquiring a sexually transmitted disease. When sober, they might express this as, “What was I thinking?” An alcohol myopia model can provide a plausible post hoc explanation. One set of alcohol myopia studies that is particularly interesting suggests a compelling explanation for driving under the influence while intoxicated with alcohol or other impairing substances. Sober college students who have been exposed to drunk-driving prevention campaigns often strongly endorse the belief that driving while impaired is irresponsible and dangerous. Even in anonymous surveys, many state that they intend to avoid drinking and driving. However, both laboratory and field studies show that when they actually are intoxicated, their responses change. Once their Blood Alcohol Level reaches a critical threshold (usually about 0.06%), they are much more likely to say that they intend to drive, particularly if their interviewer emphasizes that their intended destination (usually home) is not far away or follows a very familiar route. In such circumstances, the alcohol myopia model suggests that the desire to drive the car to an easy destination becomes paramount (salient) and the possible dangers (distant in time and likelihood) are discounted or ignored. An important further implication of this model is that it predicts (up to the point of incapacity) that the more intoxicated the person, the more likely he or she is to decide to drive while intoxicated. In fact, it predicts that the most intoxicated people are the ones most determined to drive themselves home. Gambling, smoking, overeating, and other such risky or unhealthy behaviors while intoxicated have been studied as examples of alcohol myopia. Most of this work has been field studies or surveys and questionnaires, so the findings lack the experimental rigor that laboratory studies could have. Nonetheless, myopia seems such a universally applied and appealing explanation that the number and variety of intoxicated behaviors attributed to alcohol myopia continues to grow. Recently, one group of researchers even suggested that they often found association between suicidal behavior and intoxication might result from alcohol myopia intensifying suicidal or self-destructive thoughts.
DOES ALCOHOL MYOPIA EXPLAIN HOW INTOXICATION CAN LEAD TO MORE PRUDENT BEHAVIOR? Demonstrating that intoxication is associated with poor decisions and discounting of negative consequences
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is not, in itself, differential support for an alcohol myopia versus a disinhibition explanation. Evidence providing more compelling support for alcohol myopia comes from the studies mentioned above that show a counterintuitive increase of inhibitory effects associated with acute intoxication. A disinhibition model predicts increased risky behavior, regardless of environmental cues, whereas an alcohol myopia model differentially predicts decreased risky behavior if the most salient cues in the situation promote caution rather than risk. As an example, one research group reported a series of experiments with a strong inhibitory cue (a hand stamp reading “AIDS Kills”). Volunteers had their hands stamped before they went out to socialize for the evening. Contrary to what most people would expect, it was the intoxicated participants whose hands were stamped before they went out who reported more safe sex practices than sober participants with the same hand stamp. In contrast, when participants had no hand stamp (or had a slightly less inhibitory one that read “Safe Sex”) the results were reversed: sober participants were more likely than intoxicated participants to report using protective strategies. A disinhibition hypothesis would have predicted only that intoxication would lead to riskier behavior regardless of the hand stamp, so these results are more consistent with an alcohol myopia model. Hypothetically, if a person had a frightening, intense message (AIDS Kills) stamped on the back of a hand, intoxication caused such an intense focus on the message that they were more aware of it than of other external cues. Other researchers have reported controlled studies in which intoxication was associated with more positive behavior than sobriety, again depending on which cues were most salient in the environment. Given the right stimuli, for example, intoxicated participants were more likely to be generous and helpful to others than sober participants. These results have all been interpreted as evidence that the intoxicated participants were focusing more on the emphasized very salient needs of others rather than less salient positive aspects of saving their money.
GOING BEYOND ALCOHOL: SUBSTANCE MYOPIA? To date, although alcohol myopia appears quite embedded in the scientific literature, very few studies or papers address other psychoactive substances as a source of myopia. One reported laboratory study of nicotine effects was consistent with a nicotine myopia explanation, but otherwise, no controlled studies of any substance other than alcohol were found.
Expanding myopia research to encompass other substances could be a promising method of explaining differential use as well as differential acute effects of substance use. After all, alcohol myopia explanations of behavior are linked theoretically to attention allocation models in cognitive psychology (see the discussion of inattentional blindness above). Attention allocation models are well supported in the laboratory and have been applied to a much wider range of behavior than alcohol or Substance Induced Myopia. Substance myopia research might even be characterized as a subset of attention allocation research, thus arguing even more strongly for laboratory demonstrations of parallel effects and connections with more comprehensive models of perception and decision-making. So why are so few laboratory studies of substance myopia effects published? One explanation for the lack of published substance myopia studies may be that they simply have not been tried. The cost of doing laboratory drug administration research certainly limits feasibility. Rigorous study of the acute effects of intoxication requires administration of the substance in a controlled setting in controlled doses. The expensive involved (e.g. ensuring participants’ safety and comfort until the substance has dissipated) may limit researchers’ ability, interest, and efforts to investigate these possibilities. Of course, a second possible explanation is that studies with other substances have been done, but negative or non-significant results limit their likelihood of publication. This point will enter into the discussion below.
LIMITATIONS OF MYOPIA-BASED EXPLANATION On the surface, alcohol myopia appears to have garnered much empirical support as an explanation of intoxicated behavior. However, this show of support may be misleading. Many of the studies cited as evidence for the myopia model are post hoc explanations of how associated factors may relate to one another. Findings that intoxicated people engage in risky and negative behaviors do not provide differential support for the alcohol myopia model versus the more parsimonious disinhibition explanation that it was intended to replace. The burden of support for the myopia model really falls on two types of studies: (1) those showing that counterintuitive behavior can occur during intoxication if the situational cues are manipulated and (2) those showing that distraction plays a key role in the behavior of acutely intoxicated people (e.g. the original studies by Steele and Josephs, described above). As noted above, such studies do not appear in great
I. THE NATURE OF ADDICTION
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CONCLUSIONS
abundance in the literature, so the support for the myopia model as a simple explanation is not as strong as many authors tend to suggest. Further, a few published experiments, despite careful design and execution, have reported finding no evidence for myopia. At least one of these laboratory-based experiments examining sexual aggression suggests that a more complex model of disinhibition incorporating prior individual differences in participants’ attitudes may better predict such behavior than does the alcohol myopia model (relying on situational cues). Critics of these experiments have suggested that perhaps the inhibitory cues used in the studies were not salient, but this is somewhat of a disingenuous and possibly circular argument. Alcohol myopia is actually a two-step process. First, certain cues must be salient or obvious enough to capture the participant’s attention. Second, intoxication should result in a stronger focus on those cues versus others in the environment. As discussed above in reference to attention allocation, whether a cue is salient or not depends upon the eye, or rather the brain, of the beholder (i.e. the participant). A researcher cannot declare that certain cues were salient on the basis of how the participant behaved when under the influence of alcohol. Cue saliency is an important basic element of the model and should be assessed with the specific participants in every such experimental protocol. In fact, very few studies of the alcohol myopia model have reported a separate assessment of cue saliency. Interestingly, the experiment reported above that failed to find an alcohol myopia effect on sexual aggression did, in fact, report research demonstrating salience of the inhibitory cues with the target participant sample. On a more general level, questions about natural cue saliency have been raised in support of the myopia model on the occasions whenever non-supportive results have been reported. One contention is that instigatory cues (e.g. cues to initiate sex and aggression) are naturally more salient than inhibitory cues and will always command more attention when they are present (no matter how intense the inhibitory cues may be). Again, because saliency is not often assessed separately in any of these experiments, further study is needed before such an argument can be accepted. To date, the use of the myopia model to predict and to even modify antisocial types of behavior lacks support. A recent review used the principles of an alcohol myopia model to suggest methods of decreasing alcohol-related aggression incidents, but no empirical data were presented to support these possibilities. If the model is going to be useful beyond providing explanations of behavior, research on modifying behavior is sorely needed.
Finally, another limitation of myopia research is the ongoing definition and redefinition of intoxicated myopia. Currently, there are at least two variations of the model that have developed from studies of intoxicated aggression versus studies of the use of alcohol to relieve anxiety and depression. The two similar lines of research (both using the same terms) can lead to occasional confusion, especially when findings seem to fit with one model variation but not the other. Because all of the variations tend to rely on the same principles, we have presented this introduction to myopia as a relatively unitary model.
CONCLUSIONS Substance Induced Myopia presents a cognitively based model of intoxicated behavior that has wide appeal, as evidenced by the number of times that it is cited post hoc to explain seemingly uncharacteristic actions of people when they are intoxicated. Alcohol myopia, in particular, has been used to understand intoxicated people’s decisions to drive after drinking, engage in risky sex, behave aggressively toward others, do dangerous stunts, behave suicidally, become sexually assaultive, and so on. The major premise of the myopia model is that the more intoxicated they become, the more people will focus on the most salient cues or stimuli in the environment to guide their behavior. Despite its wide acceptance, empirical support for the myopia model is not as strong as it initially appears. The best support comes from studies showing counterintuitive behavior when cues are manipulated and other studies showing that distraction is associated with relief of negative emotions (e.g. depression and anxiety) when a person is intoxicated. More research is needed especially to determine if the fundamental premises are supported (e.g. which cues are more salient than others? Are instigatory cues always more salient than inhibitory cues?). Additionally, research with psychoactive drugs beyond alcohol is necessary to establish if a myopia model is a more universal substance myopia model. Finally, and most importantly, research is needed to show that substance myopia models can reliably and accurately predict intoxicated behavior. Only then can it be useful in modifying the risky, dangerous, and unpleasant behaviors that it is meant to explain.
SEE ALSO Binge Drinking, Cognitive Factors in Addictive Processes, Impulsivity, Disinhibition, and Risk Taking in Addiction
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Glossary Attention allocation an active (but often non-conscious) process through which people direct their focus to specific stimuli in their immediate environment. No one can possibly focus on all the stimuli that impinge on the senses, so certain stimuli are selected for focus. Disinhibition inhibition describes a learned process through which a person is thought to restrain certain behavior, because the behavior might be considered socially inappropriate, potentially dangerous, hurtful to others, and so on. Consequently, disinhibition describes behavior hypothesized to occur when those restraints are lifted or temporarily disabled. A prominent explanation for alcohol and other drugs’ effects on behavior is that the substances disinhibit a person’s behavior. Drug administration laboratory studies studies in which precisely controlled doses of drugs (including alcohol) are administered to human or non-human subjects for purposes of measuring a variety of responses to those drugs. Such studies are necessary to establish cause-and-effect relationships between the substance at different doses and the participant’s behavioral responses. They are conducted in a controlled setting (usually a laboratory, although the laboratory might closely resemble a bar) in order to preserve the internal validity of the experiment by eliminating potential confounding variables. The controlled setting also protects the safety and welfare of participants by closely monitoring them until they are no longer intoxicated. Field or observational studies (of substance use) studies in which behavior associated with substance use is observed in a setting more naturalistic than the controlled laboratory. Factors associated with the substance, such as those preceding, occurring concurrently with or following consumption of the substance can be assessed. One advantage of such studies is that they can provide input to help formulate specific hypotheses about drug effects that can subsequently be tested in the laboratory. A disadvantage is that such studies can only test the strength of associations because independent variables cannot be manipulated by the researcher. Inattentional blindness the inability to “see” an object or event even though it is obvious when pointed out. Humans have a limited capacity for attention (see “attention allocation” above), so certain stimuli may not be perceived, even though they are in plain sight. Studies of inattentional blindness and associated studies of change blindness demonstrate that the mind’s selection of attentional stimuli is a very active process, but most people are not aware of the process (i.e. it is non-conscious). Inhibitory cues stimuli in the environment that signal the need for (or advisability of) restraining one’s behavior and not acting upon impulse. Instigatory cues stimuli in the environment that signal the likely availability of certain highly desired or highly rewarding consequences, such as tasty food and sexual satisfaction. Intoxication a psychophysiological state induced by the ingestion of a psychoactive substance. Once the substance has crossed the blood–brain barrier, it may disrupt normal brain functioning in a variety of ways. Some of these disruptions appear to be
pleasurable, at least initially, and probably drive the desire to consume more of the substance, even though some of the effects are harmful or potentially harmful. Intoxication is a vague term and has been used to describe only slight disruption of functioning (usually associated with a low dose of the substance) as well as extreme disruption. Post hoc explanation a hypothesis or set of hypotheses suggested “after the fact” that attempts to account for a particular event that has already happened. Post hoc explanations or hypotheses may be an interesting or intriguing method of generating testable hypotheses, but they capitalize on chance and cannot demonstrate causeand-effect relationships. Such a demonstration requires a second step: using the post hoc hypothesis to generate and test an a priori hypothesis. Tension-reduction hypothesis a prominent hypothesis regarding reasons for alcohol and other drug use that is broken down into two premises: (1) people use alcohol in order to relieve or reduce tension and (2) alcohol does, in fact, relieve or reduce tension. Two different kinds of studies are needed to test the two parts of the hypothesis. First, if a person is in an unpleasant state of tension (vaguely defined), will he or she drink more than someone who is not in a state of tension? Second, if a person is in a state of tension, can a dose of alcohol (versus a placebo) reduce or relieve that state? Empirical support for the hypothesis has been mixed, depending on how tension is defined, how dose is defined, how relief or reduction is demonstrated, and so on. Salient (stimuli or cues) the stimuli in the environment most likely to capture the person’s attention. Sometimes researchers define salient stimuli as the most obvious stimuli. However, given demonstrations of inattentional blindness, for example, salience might be difficult to define easily.
Further Reading Giancola, P., Josephs, R., Parrott, D., Duke, A., 2010. Alcohol myopia revisited: clarifying aggression and other acts of disinhibition through a distorted lens. Perspectives on Psychological Science 5, 265–278. Kassel, J., Unrod, M., 2000. Smoking, anxiety, and attention: support for the role of nicotine in attentionally mediated anxiolysis. Journal of Abnormal Psychology 109, 161–166. Leonard, K., 1989. The impact of explicit aggressive and implicit nonaggressive cues on aggression in intoxicated and sober males. Personality and Social Psychology Bulletin 15, 390–400. MacDonald, T., Fong, G., Zanna, M., Martineau, A., 2000. Alcohol myopia and condom use: can alcohol intoxication be associated with more prudent behavior? Journal of Personality and Social Psychology 78, 605–619. Noel, N.E., Maisto, S.A., Johnson, J.D., Jackson, L.A., 2009. The effects of alcohol and cue salience on young men’s acceptance of sexual aggression. Addictive Behaviors 34, 386–394. Steele, C., Josephs, R., 1990. Alcohol myopia: its prized and dangerous effects. American Psychologist 45, 921–933.
I. THE NATURE OF ADDICTION
36 Substance Induced Myopia Nora E. Noel, Jennifer A. Heaton, Brian P. Brown University of North Carolina Wilmington, Wilmington, NC, USA
O U T L I N E Definition
349
Going Beyond Alcohol: Substance Myopia?
352
Development of the Model
349
Limitations of Myopia-Based Explanation
352
Behaviors Thought to be Affected by Alcohol Myopia
Conclusions
353
351
Does Alcohol Myopia Explain How Intoxication Can Lead to More Prudent Behavior?
351
DEFINITION Substance Induced Myopia (or Substance Myopia) refers to a model often used to explain the acute effects of a psychoactive substance on a person’s subsequent behavior in a particular situation. The idea is that when taken in a significant dose, the substance interferes with attentional processes and narrows a person’s ability to perceive and comprehend all the stimuli in the environment (hence the term myopia used as an analogy to eye disorders). According to the myopia model, the higher the dose of a substance beyond a critical threshold, the more it interferes with information processing, leading the person to rely on only the most salient cues in the environment to interpret the situation. Generally, the model is referred to as alcohol myopia because the vast majority of the relevant research examines the effects of alcohol on behavior. However, from a hypothetical standpoint, intoxication with any psychoactive substance that limits attention could have a similar effect.
DEVELOPMENT OF THE MODEL The term alcohol myopia was first coined by Claude Steele and Robert Josephs in a 1990 article in Principles of Addiction, Volume 1 http://dx.doi.org/10.1016/B978-0-12-398336-7.00036-X
the American Psychologist. They were searching for an explanation for alcohol’s inconsistent effects on disinhibition as well as a related factor, anxiety reduction. A commonly assumed mechanism for alcohol’s association with risk-taking or engaging in socially unacceptable behavior is that intoxication temporarily interferes with one’s inhibitions that might normally have kept these behaviors in check. The disinhibition hypothesis posits that under normal circumstances one is inhibited by anxiety from breaking social conventions or exposing oneself to danger. Alcohol intoxication is believed to reduce that anxiety, thereby disinhibiting the person’s behavior. Much anecdotal evidence exists that show when people drink, they can become uncharacteristically nasty, unpleasant, aggressive, extroverted, sexual, and so on. As Tara MacDonald and her colleagues put it, common sense flies “out the window” and intoxicated people may engage in many risky behaviors that while sober they would not consider. Such behaviors include driving under the influence of alcohol or drugs, having sex without protection, or starting a fight with a large stranger. However, when tested under controlled conditions, such as in a laboratory, alcohol intoxication does not appear to disinhibit behavior consistently. Often, people do report less anxiety
349
Copyright Ó 2013 Elsevier Inc. All rights reserved.
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when they are intoxicated, but sometimes, unpredictably, they do not. In fact, people may become even more depressed or anxious when drinking and, in some investigations, intoxication can be associated with more prudent or altruistic behavior than sobriety. Likewise, a large amount of research on the tensionreducing effects of acute doses of alcohol (see the encyclopedia entry on the tension-reduction hypothesis) previously had shown that drinking alcohol can reduce tension or anxiety, but sometimes it does not. Tension reduction in response to alcohol intoxication is an unreliable and often unpredictable consequence. Moreover, as noted above, sometimes drinking even leads to increased tension, anxiety or depression, much to the disappointment of the person drinking for the purpose of tension reduction. To explain the inconsistent effects of intoxication Steele and Josephs proposed a cognitive mechanism (they called alcohol myopia) which they said predicted alcohol’s effects better than a disinhibition model. They defined alcohol myopia as “a state of shortsightedness in which superficially understood, immediate aspects of experience have a disproportionate influence on behavior and emotion, a state in which we can see the tree, albeit more dimly, but miss the forest altogether.” By way of explanation, an overarching principle of social cognitive research is that people’s responses to a social situation are largely influenced by how they interpret the vast array of stimuli or cues they perceive in the situation. Given the same social situation, a person may make vastly different interpretations depending on the stimuli to which he or she attends. The person’s response is then guided by their interpretation. For example, suppose a man at a party becomes interested in a woman and attempts to strike up a conversation with her. She might react by ignoring him completely or even being hostile. Such a communication would be easy to interpret and he could move on to talk to someone else. On the other hand, if she responds to his overtures with conversation, smiles and laughter at his jokes, the interaction becomes ambiguous. Is she just being polite? Is she interested, but cautious? Is she attracted to him, too? To answer these questions, he must observe her actions and the external situation to make a judgment about how he will respond to her. Obviously, it would be impossible for a person to allocate attention to every stimulus in an environment. Instead, the man focuses on his internal and the external cues in the situation that he deems important (or salient) stimuli and he filters out irrelevant cues. His internal state (he is interested in her) and his history of interacting with women may influence part of this filtering. Note that attentional
filtering is a relatively automatic (non-conscious) ongoing process that happens rapidly (in milliseconds). Quite a bit of cognitive-psychological research demonstrates that even under ordinary circumstances people can miss what should be very obvious stimuli and events if they do not fit with their expectations. For example, inattentional blindness refers to the failure to perceive an event that would be quite noticeable while engaged in an attention-demanding task. The published scientific research is compelling, but the phenomenon is also famously demonstrated by the short video posted on You Tube in which the viewer is asked to count the number of ball passes a basketball team makes. Most viewers watch the team and at the end of the video seem completely unaware that a large man in a bear costume walked right through the center of the action. After the bear is pointed out, he is very obvious on the second viewing. Thus, people are already selectively screening stimuli, often guided by what they expect, or want, to see. If we return to the man at the party, he is busy attending to social cues that could signal that the attractive woman is mutually attracted to him, unaware that he is selectively screening information he will use in his decisional process. He will use his filtered information to decide how to behave with her. According to the alcohol myopia model, if the man is or becomes intoxicated, he will be cognitively impaired, thus having an even more limited capacity to process information. The selection filter becomes tighter, narrower, and he will be capable of attending to only the most salient cues, as determined by his internal state or, perhaps, some extremely obvious cues in the situation. He is more likely to miss other important information. Thus, if sober, he might notice that she is smiling (very evident or salient to him) but also be aware that subtly she is making eye contact with other people and appears to be edging away from him. She is probably not interested in conversing with him. However, if alcohol intoxication narrows his attentional processing (i.e. he experiences alcohol myopia), he is likely to interpret her social cues incorrectly, focusing only on her salient smiling behavior, and assume that she welcomes his company. His subsequent behavior with her might be socially inappropriate and very unwelcome. To further illustrate how the myopic state might function, several researchers suggest that intoxicated men present a higher risk of sexual aggression than sober men because they focus only on their own internal sexual arousal, attending most closely to any positive behaviors exhibited by the woman, while failing to perceive or process any discouraging or negative behavior on her part. The latter cues are
I. THE NATURE OF ADDICTION
DOES ALCOHOL MYOPIA EXPLAIN HOW INTOXICATION CAN LEAD TO MORE PRUDENT BEHAVIOR?
usually less salient because they do not fit with his expectations.
BEHAVIORS THOUGHT TO BE AFFECTED BY ALCOHOL MYOPIA Researchers have conceptualized alcohol myopia as the explanation for a fairly long and varied list of alcoholrelated behavior. Initially, Steele and Josephs used the concept to explain alcohol’s inconsistent effect on anxiety, hypothesizing that in a situation where there are no distracting or more salient stimuli, intoxication may cause people to focus on the obvious, salient anxiety-producing stimuli and become more anxious, rather than less anxious after drinking. Their experiments supported their hypothesis by showing that when intoxicated people focused on an impending anxiety-provoking event, they became more anxious, but, in contrast, when intoxicated participants were given a distracting task, more attention-demanding than the anxiety-provoking event, they became less anxious. Similarly, results of some observational and survey studies suggest that people may drink to escape or relieve depression (e.g. drown their sorrows), only to find themselves more depressed (e.g. crying in my beer) as they become more intoxicated. Thus, proponents of the alcohol myopia model have suggested that merely drinking, without engaging in an attention-grabbing distraction, leads to a focus on the person’s internal state of depression, which then intensifies. Other researchers have hypothesized that alcohol myopia plays a key role in alcohol-related aggression. Laboratory studies support the idea that alcohol consumption may increase aggression because the intoxicated individual focuses on reasons for fighting (e.g. “This person insulted me.” “This person stepped ahead of me in line.” “This person bumped me intentionally.”). Reasons for fighting are often quite salient in a drinking situation such as a loud bar or party. According to the model, the alcohol-myopic person loses awareness of less obvious circumstances, both external (e.g. “That person has friends here.”) and internal (e.g. “I don’t want to fight with someone. I’d rather just have a quiet evening.”) that might normally limit their aggression. He or she then reacts with aggression. In a similar vein, many researchers suggest that alcohol-related sexual aggression increases when cues for the instigation of sexual behavior are more salient than cues inhibiting sex. According to the model, the intoxicated sexually aroused man might believe that he has the right to demand or force sex from his partner, perhaps because he thinks that the she instigated sex. Her sexual cues are salient to him and her protests are not. Moreover, several studies of risky sex, such as having sex with an unknown partner or without a condom,
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support the idea that when both parties are intoxicated they are likely to focus exclusively on their sexual arousal (the salient stimulus) and ignore less salient concerns such as becoming involved with an inappropriate partner, becoming pregnant, or acquiring a sexually transmitted disease. When sober, they might express this as, “What was I thinking?” An alcohol myopia model can provide a plausible post hoc explanation. One set of alcohol myopia studies that is particularly interesting suggests a compelling explanation for driving under the influence while intoxicated with alcohol or other impairing substances. Sober college students who have been exposed to drunk-driving prevention campaigns often strongly endorse the belief that driving while impaired is irresponsible and dangerous. Even in anonymous surveys, many state that they intend to avoid drinking and driving. However, both laboratory and field studies show that when they actually are intoxicated, their responses change. Once their Blood Alcohol Level reaches a critical threshold (usually about 0.06%), they are much more likely to say that they intend to drive, particularly if their interviewer emphasizes that their intended destination (usually home) is not far away or follows a very familiar route. In such circumstances, the alcohol myopia model suggests that the desire to drive the car to an easy destination becomes paramount (salient) and the possible dangers (distant in time and likelihood) are discounted or ignored. An important further implication of this model is that it predicts (up to the point of incapacity) that the more intoxicated the person, the more likely he or she is to decide to drive while intoxicated. In fact, it predicts that the most intoxicated people are the ones most determined to drive themselves home. Gambling, smoking, overeating, and other such risky or unhealthy behaviors while intoxicated have been studied as examples of alcohol myopia. Most of this work has been field studies or surveys and questionnaires, so the findings lack the experimental rigor that laboratory studies could have. Nonetheless, myopia seems such a universally applied and appealing explanation that the number and variety of intoxicated behaviors attributed to alcohol myopia continues to grow. Recently, one group of researchers even suggested that they often found association between suicidal behavior and intoxication might result from alcohol myopia intensifying suicidal or self-destructive thoughts.
DOES ALCOHOL MYOPIA EXPLAIN HOW INTOXICATION CAN LEAD TO MORE PRUDENT BEHAVIOR? Demonstrating that intoxication is associated with poor decisions and discounting of negative consequences
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is not, in itself, differential support for an alcohol myopia versus a disinhibition explanation. Evidence providing more compelling support for alcohol myopia comes from the studies mentioned above that show a counterintuitive increase of inhibitory effects associated with acute intoxication. A disinhibition model predicts increased risky behavior, regardless of environmental cues, whereas an alcohol myopia model differentially predicts decreased risky behavior if the most salient cues in the situation promote caution rather than risk. As an example, one research group reported a series of experiments with a strong inhibitory cue (a hand stamp reading “AIDS Kills”). Volunteers had their hands stamped before they went out to socialize for the evening. Contrary to what most people would expect, it was the intoxicated participants whose hands were stamped before they went out who reported more safe sex practices than sober participants with the same hand stamp. In contrast, when participants had no hand stamp (or had a slightly less inhibitory one that read “Safe Sex”) the results were reversed: sober participants were more likely than intoxicated participants to report using protective strategies. A disinhibition hypothesis would have predicted only that intoxication would lead to riskier behavior regardless of the hand stamp, so these results are more consistent with an alcohol myopia model. Hypothetically, if a person had a frightening, intense message (AIDS Kills) stamped on the back of a hand, intoxication caused such an intense focus on the message that they were more aware of it than of other external cues. Other researchers have reported controlled studies in which intoxication was associated with more positive behavior than sobriety, again depending on which cues were most salient in the environment. Given the right stimuli, for example, intoxicated participants were more likely to be generous and helpful to others than sober participants. These results have all been interpreted as evidence that the intoxicated participants were focusing more on the emphasized very salient needs of others rather than less salient positive aspects of saving their money.
GOING BEYOND ALCOHOL: SUBSTANCE MYOPIA? To date, although alcohol myopia appears quite embedded in the scientific literature, very few studies or papers address other psychoactive substances as a source of myopia. One reported laboratory study of nicotine effects was consistent with a nicotine myopia explanation, but otherwise, no controlled studies of any substance other than alcohol were found.
Expanding myopia research to encompass other substances could be a promising method of explaining differential use as well as differential acute effects of substance use. After all, alcohol myopia explanations of behavior are linked theoretically to attention allocation models in cognitive psychology (see the discussion of inattentional blindness above). Attention allocation models are well supported in the laboratory and have been applied to a much wider range of behavior than alcohol or Substance Induced Myopia. Substance myopia research might even be characterized as a subset of attention allocation research, thus arguing even more strongly for laboratory demonstrations of parallel effects and connections with more comprehensive models of perception and decision-making. So why are so few laboratory studies of substance myopia effects published? One explanation for the lack of published substance myopia studies may be that they simply have not been tried. The cost of doing laboratory drug administration research certainly limits feasibility. Rigorous study of the acute effects of intoxication requires administration of the substance in a controlled setting in controlled doses. The expensive involved (e.g. ensuring participants’ safety and comfort until the substance has dissipated) may limit researchers’ ability, interest, and efforts to investigate these possibilities. Of course, a second possible explanation is that studies with other substances have been done, but negative or non-significant results limit their likelihood of publication. This point will enter into the discussion below.
LIMITATIONS OF MYOPIA-BASED EXPLANATION On the surface, alcohol myopia appears to have garnered much empirical support as an explanation of intoxicated behavior. However, this show of support may be misleading. Many of the studies cited as evidence for the myopia model are post hoc explanations of how associated factors may relate to one another. Findings that intoxicated people engage in risky and negative behaviors do not provide differential support for the alcohol myopia model versus the more parsimonious disinhibition explanation that it was intended to replace. The burden of support for the myopia model really falls on two types of studies: (1) those showing that counterintuitive behavior can occur during intoxication if the situational cues are manipulated and (2) those showing that distraction plays a key role in the behavior of acutely intoxicated people (e.g. the original studies by Steele and Josephs, described above). As noted above, such studies do not appear in great
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abundance in the literature, so the support for the myopia model as a simple explanation is not as strong as many authors tend to suggest. Further, a few published experiments, despite careful design and execution, have reported finding no evidence for myopia. At least one of these laboratory-based experiments examining sexual aggression suggests that a more complex model of disinhibition incorporating prior individual differences in participants’ attitudes may better predict such behavior than does the alcohol myopia model (relying on situational cues). Critics of these experiments have suggested that perhaps the inhibitory cues used in the studies were not salient, but this is somewhat of a disingenuous and possibly circular argument. Alcohol myopia is actually a two-step process. First, certain cues must be salient or obvious enough to capture the participant’s attention. Second, intoxication should result in a stronger focus on those cues versus others in the environment. As discussed above in reference to attention allocation, whether a cue is salient or not depends upon the eye, or rather the brain, of the beholder (i.e. the participant). A researcher cannot declare that certain cues were salient on the basis of how the participant behaved when under the influence of alcohol. Cue saliency is an important basic element of the model and should be assessed with the specific participants in every such experimental protocol. In fact, very few studies of the alcohol myopia model have reported a separate assessment of cue saliency. Interestingly, the experiment reported above that failed to find an alcohol myopia effect on sexual aggression did, in fact, report research demonstrating salience of the inhibitory cues with the target participant sample. On a more general level, questions about natural cue saliency have been raised in support of the myopia model on the occasions whenever non-supportive results have been reported. One contention is that instigatory cues (e.g. cues to initiate sex and aggression) are naturally more salient than inhibitory cues and will always command more attention when they are present (no matter how intense the inhibitory cues may be). Again, because saliency is not often assessed separately in any of these experiments, further study is needed before such an argument can be accepted. To date, the use of the myopia model to predict and to even modify antisocial types of behavior lacks support. A recent review used the principles of an alcohol myopia model to suggest methods of decreasing alcohol-related aggression incidents, but no empirical data were presented to support these possibilities. If the model is going to be useful beyond providing explanations of behavior, research on modifying behavior is sorely needed.
Finally, another limitation of myopia research is the ongoing definition and redefinition of intoxicated myopia. Currently, there are at least two variations of the model that have developed from studies of intoxicated aggression versus studies of the use of alcohol to relieve anxiety and depression. The two similar lines of research (both using the same terms) can lead to occasional confusion, especially when findings seem to fit with one model variation but not the other. Because all of the variations tend to rely on the same principles, we have presented this introduction to myopia as a relatively unitary model.
CONCLUSIONS Substance Induced Myopia presents a cognitively based model of intoxicated behavior that has wide appeal, as evidenced by the number of times that it is cited post hoc to explain seemingly uncharacteristic actions of people when they are intoxicated. Alcohol myopia, in particular, has been used to understand intoxicated people’s decisions to drive after drinking, engage in risky sex, behave aggressively toward others, do dangerous stunts, behave suicidally, become sexually assaultive, and so on. The major premise of the myopia model is that the more intoxicated they become, the more people will focus on the most salient cues or stimuli in the environment to guide their behavior. Despite its wide acceptance, empirical support for the myopia model is not as strong as it initially appears. The best support comes from studies showing counterintuitive behavior when cues are manipulated and other studies showing that distraction is associated with relief of negative emotions (e.g. depression and anxiety) when a person is intoxicated. More research is needed especially to determine if the fundamental premises are supported (e.g. which cues are more salient than others? Are instigatory cues always more salient than inhibitory cues?). Additionally, research with psychoactive drugs beyond alcohol is necessary to establish if a myopia model is a more universal substance myopia model. Finally, and most importantly, research is needed to show that substance myopia models can reliably and accurately predict intoxicated behavior. Only then can it be useful in modifying the risky, dangerous, and unpleasant behaviors that it is meant to explain.
SEE ALSO Binge Drinking, Cognitive Factors in Addictive Processes, Impulsivity, Disinhibition, and Risk Taking in Addiction
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Glossary Attention allocation an active (but often non-conscious) process through which people direct their focus to specific stimuli in their immediate environment. No one can possibly focus on all the stimuli that impinge on the senses, so certain stimuli are selected for focus. Disinhibition inhibition describes a learned process through which a person is thought to restrain certain behavior, because the behavior might be considered socially inappropriate, potentially dangerous, hurtful to others, and so on. Consequently, disinhibition describes behavior hypothesized to occur when those restraints are lifted or temporarily disabled. A prominent explanation for alcohol and other drugs’ effects on behavior is that the substances disinhibit a person’s behavior. Drug administration laboratory studies studies in which precisely controlled doses of drugs (including alcohol) are administered to human or non-human subjects for purposes of measuring a variety of responses to those drugs. Such studies are necessary to establish cause-and-effect relationships between the substance at different doses and the participant’s behavioral responses. They are conducted in a controlled setting (usually a laboratory, although the laboratory might closely resemble a bar) in order to preserve the internal validity of the experiment by eliminating potential confounding variables. The controlled setting also protects the safety and welfare of participants by closely monitoring them until they are no longer intoxicated. Field or observational studies (of substance use) studies in which behavior associated with substance use is observed in a setting more naturalistic than the controlled laboratory. Factors associated with the substance, such as those preceding, occurring concurrently with or following consumption of the substance can be assessed. One advantage of such studies is that they can provide input to help formulate specific hypotheses about drug effects that can subsequently be tested in the laboratory. A disadvantage is that such studies can only test the strength of associations because independent variables cannot be manipulated by the researcher. Inattentional blindness the inability to “see” an object or event even though it is obvious when pointed out. Humans have a limited capacity for attention (see “attention allocation” above), so certain stimuli may not be perceived, even though they are in plain sight. Studies of inattentional blindness and associated studies of change blindness demonstrate that the mind’s selection of attentional stimuli is a very active process, but most people are not aware of the process (i.e. it is non-conscious). Inhibitory cues stimuli in the environment that signal the need for (or advisability of) restraining one’s behavior and not acting upon impulse. Instigatory cues stimuli in the environment that signal the likely availability of certain highly desired or highly rewarding consequences, such as tasty food and sexual satisfaction. Intoxication a psychophysiological state induced by the ingestion of a psychoactive substance. Once the substance has crossed the blood–brain barrier, it may disrupt normal brain functioning in a variety of ways. Some of these disruptions appear to be
pleasurable, at least initially, and probably drive the desire to consume more of the substance, even though some of the effects are harmful or potentially harmful. Intoxication is a vague term and has been used to describe only slight disruption of functioning (usually associated with a low dose of the substance) as well as extreme disruption. Post hoc explanation a hypothesis or set of hypotheses suggested “after the fact” that attempts to account for a particular event that has already happened. Post hoc explanations or hypotheses may be an interesting or intriguing method of generating testable hypotheses, but they capitalize on chance and cannot demonstrate causeand-effect relationships. Such a demonstration requires a second step: using the post hoc hypothesis to generate and test an a priori hypothesis. Tension-reduction hypothesis a prominent hypothesis regarding reasons for alcohol and other drug use that is broken down into two premises: (1) people use alcohol in order to relieve or reduce tension and (2) alcohol does, in fact, relieve or reduce tension. Two different kinds of studies are needed to test the two parts of the hypothesis. First, if a person is in an unpleasant state of tension (vaguely defined), will he or she drink more than someone who is not in a state of tension? Second, if a person is in a state of tension, can a dose of alcohol (versus a placebo) reduce or relieve that state? Empirical support for the hypothesis has been mixed, depending on how tension is defined, how dose is defined, how relief or reduction is demonstrated, and so on. Salient (stimuli or cues) the stimuli in the environment most likely to capture the person’s attention. Sometimes researchers define salient stimuli as the most obvious stimuli. However, given demonstrations of inattentional blindness, for example, salience might be difficult to define easily.
Further Reading Giancola, P., Josephs, R., Parrott, D., Duke, A., 2010. Alcohol myopia revisited: clarifying aggression and other acts of disinhibition through a distorted lens. Perspectives on Psychological Science 5, 265–278. Kassel, J., Unrod, M., 2000. Smoking, anxiety, and attention: support for the role of nicotine in attentionally mediated anxiolysis. Journal of Abnormal Psychology 109, 161–166. Leonard, K., 1989. The impact of explicit aggressive and implicit nonaggressive cues on aggression in intoxicated and sober males. Personality and Social Psychology Bulletin 15, 390–400. MacDonald, T., Fong, G., Zanna, M., Martineau, A., 2000. Alcohol myopia and condom use: can alcohol intoxication be associated with more prudent behavior? Journal of Personality and Social Psychology 78, 605–619. Noel, N.E., Maisto, S.A., Johnson, J.D., Jackson, L.A., 2009. The effects of alcohol and cue salience on young men’s acceptance of sexual aggression. Addictive Behaviors 34, 386–394. Steele, C., Josephs, R., 1990. Alcohol myopia: its prized and dangerous effects. American Psychologist 45, 921–933.
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