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Denial and Lack of Awareness in Substance Dependence
C H A P T E R
8 Denial and Lack of Awareness in Substance Dependence: Insights from the Neuropsychology of Addiction A. Verdejo-Garcı´a*, M.J. Fernandez-Serrano$, J. Tirapu-Ustarroz** *
Institute of Neuroscience F. Olo´riz, Universidad de Granada, Granada, Spain, $Department of Psychology, Universidad de Jae´n, Jae´n, Spain, **Clı´nica Ubarmin, Egu¨e´s-Navarra, Spain
O U T L I N E Introduction
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Awareness, Lie, and Denial in Addiction: A Neuroscientific Approach Self-Awareness Denial
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About Lie Self-Awareness, Denial, and Cognitive Deficits
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Conclusions and Clinical Implications
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INTRODUCTION
Continuous exposure to drug use turns these impulsive behaviors into habits, that is, impulsivity gives way to compulsion, thus consolidating motor programs that go off automatically in the presence or anticipation of drug-related signals. Repeated consumption also provokes important changes in the interoceptive and emotional systems. Recent studies highlight the role that detection of body signals related to drug-taking experiences plays in the generation of emotional states leading to drug-seeking behavior, such as craving. In addition, a persistent sensitization of the stress systems takes place and the drug-seeking behavior rockets in an attempt to rebalance the body’s hedonic tone. Alongside this adaptation of the motivational and affective systems, addiction is associated with a deterioration of the executive control mechanisms, which depend on the functioning of the prefrontal cortex. The dysfunction of executive mechanisms leads to alterations of processes which are considered of a more cognitive nature, such as the ability to update and monitor multiple sources of information (cognitive, affective, and motivational) aiming to design plans and reach
Substance use and dependence is characterized by a difficulty to control consumption and a tendency to persistence despite its increasing adverse consequences (DSM-IV, CIE-10). Current neuropsychological models conceive addiction as a neuroadaptive process leading to significant alterations in the frontal-striatal circuits, including several sections of the prefrontal cortex (orbitofrontal, dorsolateral, and medial), limbic and paralimbic regions (amygdala, hippocampus, insula), and basal ganglia. Alterations in these circuits affect the activity of the motivational, emotional, and executive control systems. Dysfunction of motivational systems is made evident by the overestimation of the reinforcing, adaptive value of drug-related stimuli and the underestimation of the value of other natural reinforcers, fundamental to our survival. This motivational bias promotes the development of impulsive behaviors, which are fostered by the expectation of immediate reinforcement (drug use–related), whereas little consideration is given to its potential, long-term consequences. Principles of Addiction, Volume 1 http://dx.doi.org/10.1016/B978-0-12-398336-7.00008-5
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Copyright Ó 2013 Elsevier Inc. All rights reserved.
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goals. In addition, it hinders the ability to inhibit and effectively switch response patterns according to the changing demands in the environment, as well as the capability for making adaptive decisions that guarantee both our survival and our survival quality. The notion of lack of awareness of addiction and its consequences is inherent in a number of the neuropsychological dysfunctions reviewed above. Neuroadaptations in interoceptive, motivational, and affective systems may contribute to a persisting attentional bias on drug-related needs that prevents considering other homeostatic signals. The results of recent neuroimaging studies show that dysfunction of the insula (a key region for processing and integrating interoceptive signals) may underlie the difficulties of addicted individuals to gain access to the emotional signals that are necessary to realize the implications of the disorder and develop alternative behaviors. In addition, the consolidation of an impulsive response pattern implies a lack of consideration of the input associated to delayed information, which would include most of the negative consequences of addiction. In this sense, we know that the ability to imagine future emotional events is related to the functioning of the medial orbitofrontal cortex, one of the most affected regions by addiction. On the other hand, once the addictive process is established, many processes oriented to drug seeking and taking (e.g. programming of motor habits) may operate in a sophisticated manner without full conscious supervision or control. Finally, dysfunction of executive mechanisms affects mainly the individual’s ability to maintain the correspondence between intention and action and to compile all necessary information to become aware of his/her deficits and their repercussions on the family milieu and social environment. To sum up, to be aware of the symptoms and repercussions of any disorder, we need to have access to all relevant information (internal and external) and be able to properly compile and monitor this information to understand its implications and use it to establish goals and implement change-oriented behaviors. In addiction, however, we find that many processes underlying these capacities are significantly deteriorated. In these cases we may talk about lack of awareness – but not denial as a meta-cognitive deficit resulting from deterioration of information processing and integration at different levels. This deterioration is linked to the dysfunction of frontal-striatal circuits involved in addiction. The concept of denial implies an implicit knowledge that can be accessed depending on the state of the organism in a particular situation, as well as an elaboration process aimed to minimize or suppress this input. Parallel neuroadaptive processes typical of addiction can also help understand this phenomenon. In their extreme form, denial processes could be compared
with the symptoms of confabulation observed in neurological patients. Symptoms of confabulation are common in patients with damage in the medial orbitofrontal cortex, one of the key brain regions both in selfreferential processes and in addiction. There is evidence that confabulations in these patients are related to (not necessarily conscious) efforts to maintain a positive self-concept or a self-referential sense of coherence, thus building a valid argumentation to maintain a status quo that will not put their own identity at risk. These confabulation mechanisms oriented to maintain a status quo could help explain the phenomenon of denial in addicted individuals. On the other hand, partial access to input regarding disorder implications may exacerbate the reactivity of the stress systems, leading to intense discomfort and undermining the individual’s selfefficacy expectations on his/her capacity to cope with the problem. This unbearable rise in stress levels makes the individual react by expelling this information from his/her conflict resolution system. These psychological processes would depend on the dialog between the brain regions responsible for the motivation and conflict (anterior cingulate cortex) and the neuroendocrine systems regulating the response to stress (hypothalamic– pituitary–adrenal axis), which are persistently altered in the addictive processes. Other authors have also highlighted the role of the cross-talk between the cognitive styles of both brain hemispheres (right hemisphere, specializing in processing novelty vs. left hemisphere, specializing in contextualizing information according to preestablished patterns) as a substrate of these dissociations. Finally, a milder form of denial may result from the predominance of motivational resources driving drug seeking and taking on those resources in charge of motivation to change. In these cases patients would be partially aware of their disorder and the need for change, but they would tend to minimize or defer it. Classical models on stages of change claim that denial would be a process inherent to the precontemplation stage. In this stage the individual considers the possibility of changing his/her drug use behavior but may deny the problem in different manners, including resignation due to lack of selfefficacy necessary to produce change, or deferral of the change. In agreement with this notion, recent studies indicate that drug users present decision styles characterized by procrastination. In sum, we understand lack of awareness and denial are two separable neuropsychological processes. However, we believe that they both have underlying neuropsychological (motivational, emotional, and meta-cognitive) alterations related to addiction-related neuroadaptations in frontal-striatal circuits. In the following sections we shall: (1) define a neuroscientific conceptual framework to understand the phenomena
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of lack of awareness, denial, and lie in addiction; (2) describe the relationship between neuropsychological processes and symptoms of anosognosia and denial; and (3) review the empirical studies having dealt with this phenomenon from different approaches over the last decade.
AWARENESS, LIE, AND DENIAL IN ADDICTION: A NEUROSCIENTIFIC APPROACH Self-Awareness Being conscious and the conscious experience may be explained by models based on the more proximal brain function, related to general neuronal action patterns. However, we all agree that awareness is more than that. When we say that someone is not aware of something, we are referring not only to tacit knowledge, but also to other relevant aspects, such as the implications of that knowledge. In the case of addiction, when we talk about lack of awareness, we refer not only to aspects such as insight of the cognitive deficits associated with drug use, but also to awareness itself about suffering this disorder. The latter would be more closely linked to the concepts of self-awareness and self-concept, which use defense or self-protection mechanisms to avoid the emotional consequences of accepting that one suffers a disorder. Self-awareness has been defined as a human tribute that allows not only awareness of the self but also awareness of one’s position in his/her social environment. In a hierarchical organization of mental functions, the ability of self-awareness would be in the vertex of the pyramid, since its function is to control one’s own mental activity, representing current experiences in relation to previous ones, using acquired knowledge to solve new situations, or guiding decision making for the future. According to Prigatano, selfawareness is the ability to perceive oneself in relatively objective terms, maintaining a sense of subjectivity. This aspect of self-awareness implies a cognitive process, as well as an emotional state, and the integration of both. The critical neural system for self-awareness is located in the prefrontal cortices, whose neuroanatomic position favors this purpose because (1) they receive signals stemming from all sensory regions where conscious experiences are formed (including images making part of our thoughts); (2) they receive signals from somatosensory cortices representing past and current body states; (3) they receive signals from bioregulatory sectors of the brain, among which neurotransmitters of the brainstem and basal prosencephalon, as well as the amygdala, the anterior cingulate, and the
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hypothalamus; and (4) they categorize the situations that affect the body, that is, they classify any contingencies in our life experience. Therefore, the prefrontal cortex is often a convergence zone that works as a deposit of dispositional representations for properly categorized, unique contingencies of our life experience. In this sense, it seems evident that, to exist, selfawareness needs information from signals coming from both outside of the self and our thoughts (which are also images). Also, it needs to have access to previously categorized information (the categorization criteria are probably based on the emotional value of the experiences). At this point, we create representations that become unique dispositions, as they are based on our life experience, which is also unique. From this point of view, and according to Stuss and colleagues, the alterations of awareness related to lesions in the prefrontal cortex have some peculiarities that should be taken into account: (1) these alterations are connected to the self and become evident generally in behavioral rather than cognitive functioning; (2) these alterations may occur irrespective of any cognitive or sensory deficits, even with an intact IQ; (3) executive functions (i.e. higher order abilities involved in the generation and control of goal-directed behavior) are important, since they are more specifically related to prefrontal systems and their damage may be linked with the alteration in awareness of deficits in behavioral functioning; (4) there may be a fractioning of awareness in relation to specific connections between the prefrontal cortex and other specific regions; (5) self-awareness is more than mere knowledge, it is the ability to reflect on the implications of this knowledge; and (6) selfawareness does not only refer to the past and the present, but it also projects to the future. In this sense, we would depict awareness not only as knowledge, since knowledge does not have implications if devoid of emotional valence. In the case of addiction, structural and functional alterations in the prefrontal cortex have been described by several neuroimaging studies in abusers of a number of drugs. Furthermore, the main corollaries of prefrontal cortex–related awareness alterations largely overlap with the neuropsychological alterations described in addicted individuals. Specifically, addicted individuals: (1) show a wide range of behavioral alterations associated with the functioning of the circuits connecting the prefrontal cortex with subcortical regions and basal ganglia (including symptoms of apathy, disinhibition, and behavioral disorganization); (2) show important alterations in executive functions, even in the presence of normal, general cognitive functions and IQ; (3) have problems to think about the consequences that these and other drug use-related alterations bring about in their daily functioning and their family milieu and social environment; and (4) show difficulties
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in associating cognitive scenarios with appropriate emotional states, especially when it comes to anticipate emotional consequences associated with future events. This more neuropsychological approach claims that there are different forms of deteriorated awareness, depending on the brain systems suffering the damage or dysfunction. In Fig. 8.1 we present a schematic representation of the different brain systems linked to awareness-related deficits. In this line, neuroscientific models have proposed in a generic manner that bilateral lesions of the frontal cortex are specifically associated with the lack of awareness on social behavior and executive functions, and with self-awareness as a whole. Clinical experience shows that there is a particular type of awareness for each knowledge module, which is fed by updated information from that particular module, whose goal is to guarantee the best adjustment of the individual. In this sense it seems that this
awareness for each specific area is affected when the brain damage affects the function and its awareness locus. We must take into account that addiction-related brain alterations may interfere with the neural substrate of self-awareness. Therefore, if a prejudicial drug use pattern produces a deficit in the cognitive, emotional, and behavioral sphere that the subject is not aware of, this lesion affects both the locus of the relative processes and the locus of their awareness. In other words, it would affect the cognitive function, the emotional sphere or its behavioral patterns, as well as the metacognition of the cognitive, emotional, or behavioral function. We could state, in a graphic manner, that the individual does not know that he/she does not know and this first aspect would make reference to concepts such as change of personality, suffering provoked to others, empathy, etc. In addition, awareness for a specific knowledge module may be affected by the degradation
FIGURE 8.1 Schematic representation of the main brain regions supporting awareness and denial-related deficits in substance-dependent individuals. 1. Right dorsolateral prefrontal cortex (Panel A) and right medial orbitofrontal cortex (Panel B), along with insula (Panel C), are involved in deficits of lack of awareness. 2. Interhemispheric right-left cross-talk or connections between anterior cingulate cortex and stress systems stemming from hypothalamus mediate processes of denial (Panel D). 3. Medial/lateral orbitofrontal cortices and frontal pole are key structures for the emergence of confabulations (Panels A and B). 4. Dorsolateral prefrontal cortex and dorsal anterior cingulate control are necessary systems for lie (Panels A and D).
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of feedback of its response or output or because the internal representation of the cognitive processes is also affected as a result of the brain impairment. For example, drug use may affect attentional mechanisms, which would lead to a degradation of the information sent to the brain. Thus, the subject cannot be aware due to the affectation of input mechanisms (Wernicke’s aphasia may be the clearest example in neurological patients). In other words, we find that drug use leads to the affectation of cognitive, emotional, and behavioral functions, as well as the affectation of cognitive, emotional, and behavioral mechanisms implied in selfknowledge and self-awareness.
Denial Some studies have proposed the existence of different kinds of alteration of awareness of one deficit according to the three basic levels of information processing: information collection, neuropsychological, and emotional. Thus, the lack of awareness itself would be the result of the patient not receiving information or this information being degraded. Also, it is possible that the patient does not understand the meaning of the information (e.g. it has been proved that alcoholic people have difficulties in processing faces expressing some basic emotions, such as sadness, relevant to understand damage inflicted to others). Regarding the level of implication of this information, the subject cannot take the self as an object or understand the implication of the deficit.
Additionally, the arousal level for awareness may also be poor (a phenomenon frequently observed in benzodiazepine or opiate addicts). In this case, the deficit occurs at the information processing and access level. However, there are other phenomena related to the lack of awareness of different nature and characteristics. The phenomenon of minimization is characterized by the fact that the patient cannot understand or extract his/ her own consequences and/or implications from the information. On an emotional level, the patient knows but cannot stand the effect of the information, thus reducing it to tolerance levels. Finally, in the case of denial, the patient has an implicit knowledge about the problem, but he/she cannot believe the information, which is too stressful, and expels it from his/her aware experience (see Table 8.1). On the other hand, studies have shown that denial observed in some chronic alcohol abusers does not necessarily need to be explained as a consequence of a maladaptive defense of the self, but as a manifestation of the neurotoxic effects of alcohol. Prigatano has investigated the alterations in awareness of deficits in patients suffering brain damage, based on Weinstein’s pioneer studies in the 1950s. Weinstein reckoned that the way that patients adapt and symbolically represent (a term with dynamic connotations) their deficits is determined by a series of factors, such as: (1) the type, severity, and location of brain damage; (2) the nature of the incapability; (3) the meaning that this deficit may have in terms of premorbid values and
TABLE 8.1 Nature of the Consciousness Problem Considering Three Possible Levels of Information Processing Nature of the consciousness problem
Level 1 e Information
Level 2 e Implications (Neuropsychological)
Level 3 e Integration (Emotional)
Lack of awareness
- The individual cannot access the information. - The individual has not enough cognitive resources to understand the meaning of the information. - Main symptom is anosognosia.
- The individual cannot take the “self” as an object. - The individual cannot understand the information. - The individual cannot retain or remember the information. - Insufficient arousal for full conscious experience.
- No strong emotional implications.
Minimization
- No alterations at this level.
- The individual cannot extract from the information its consequences and implications.
- The individual knows but cannot tolerate the effect of the information, thus reducing it to tolerance levels.
Denial
- No alterations at this level.
- No major neuropsychological alterations although sensitization of stress systems and cross-talk between conflict control and stress systems or right vs. left hemispheres cognitive styles may contribute.
- The individual cannot believe the information, it’s too stressing and therefore it is expelled from conscious experience.
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experiences; and (4) the context in which the behavior is elicited and observed. According to Weinstein, denial must be understood as a loss of insight and is related to confabulation, lie, or symbolic disorientation. Also, Weinstein exposed the importance of premorbid personality factors to understand the mechanisms of denial, as well as the presence of implicit knowledge. In this sense, the mechanisms of denial are adaptive as long as they represent and explain the patient’s incapability, giving it a sense of reality. In this line, Prigatano claims that denial of a deficit is due to several factors affecting superior levels of brain integration. In this sense, the cognitive capability of patients with brain dysfunction may be affected in evaluating the feedback about their functional limitations received from the environment. In addition, and despite receiving information about their own problems and limitations from the environmental feedback, they persist in maintaining a somewhat indifferent attitude toward this information. In fact, recent studies seem to prove that the insula plays an important role in the awareness of affective states, perhaps because the information on these affective states is produced by the brain mapping of associated body states. These connections may contribute to explain why in addiction profoundly altered body states and behavioral problems do not lead to full recognition of the disorder (see Fig. 8.1).
About Lie Lie is a constant in approaching the phenomenon of drug addictions, contaminating very often the therapeutic relationship with patients. Lie does not refer to the consumption of toxics alone; deception goes beyond that and has to do with the perception of the problem. In fact, it is surprising that a patient denies having problems with his/her partner, children, or at work due to alcohol use (alteration of central awareness), and even more that he/she can create an unreal autobiographic story, where there seems to be no problem whatsoever (alteration of extended awareness). In therapeutic intervention, it is frequent to find patients that deceive or lie. In fact, distrust in patients’ claims is the ultimate cause of taking urine samples for analysis. The first question is: why do patients lie? The response is simple: what do they win by telling the truth? Cognitive psychology suggests that a basic stone for the treatment of drug addicts is anticipation of the consequences of their behavior, so that they will behave accordingly. This leads to a second question: to what point do they need to anticipate? The variable time is essential in brain functioning: if the anticipated consequences are negative in the short term, behavior inhibits the truth. It is a brain functioning mechanism: my brain has an image of what I am and how I am; a self-
protecting image that compares data coming from experience to expel them if they contradict the image of myself, thus maintaining my status quo. There are patients that obviously know that they are lying, but they do it to protect themselves from the consequences of truth. When a subject generates mental images of the consequences of being honest, these images generate a negative emotion that inhibits the behavior, thus lie having an adaptive preservation value. Actually, it can be claimed that awareness is a human tribute that allows realizing the own reality and position in the social environment. Lie can, therefore, maintain the concept of reality and social status. In this sense, it can be claimed that the lack of awareness of a problem has the invented truth as a basic pillar to convert subjectivity into objectivity, so that this subjective, unique, private interpretation of my reality will be perceived by others in the way I perceive it. This will allow my maintaining the situation and more importantly the image I have of myself. Trivers has suggested an ingenious explanation of the evolution of self-deception: in everyday life there are many situations where we need to lie. In this regard, researchers like Ekman have proved that liars always give themselves away with a somewhat feigned smile, an expression of tension, or a false tone of voice that can be detected by others. This is because the limbic system (involuntary and prone to tell the truth) controls the spontaneous expressions, whereas the facial expressions we make when we lie are controlled by the cortex (not only responsible for the voluntary control, but also the place where lies are invented). For Trivers, this problem has a solution: to effectively lie to another person, it is necessary to lie to oneself first. If we believe that the thing we are saying is true, our expressions will be real, with no trace of deception. However, this statement incurs into an internal contradiction, since it contradicts the proposal of self-deception, which implies that one can have access to the truth at any time; otherwise, self-deception would no longer be adaptive. Ramachandran proposes a way to avoid this problem and states that a belief is not necessarily unitary: it is possible that self-deception is located in the left hemisphere, whereas the right hemisphere continues to know the truth. For this author, the key for self-deception lies in the working division between both brain hemispheres and our need to create a feeling of coherence and continuity in our lives. It is well known that the brain consists of two symmetrical halves, each of which specializes in different mental capabilities; the most noticeable brain asymmetry is related to language. Alongside these known function divisions, Ramachandran suggests the existence of an even more essential difference between the cognitive styles of both hemispheres, which can help explain the modalities of denial and lack of awareness. In this regard, Gazzaniga’s
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research on split brain is most revealing. This author has studied a series of patients with a disconnection between both hemispheres, which allows us to know the information stored by each of them separately. In Case P.S., one of the paradigmatic cases reported, the individual’s left hemisphere is asked what he wants to do after finishing school, the answer being: I want to be a draftsman. However, when the right hemisphere is asked the same question, the answer was: automobile racer. This case, like others in the literature, proves that both brain hemispheres live different realities and suggests that everyone can have a mute brain inside the head with a reality and a perception of oneself very different to what we daily believe we are. In any moment of life, the brain can feel overwhelmed by a continuous information cascade that must be integrated into a coherent perspective of the own image and the image that others expect from oneself. To generate coherent actions or to maintain a given status quo, the brain must have a type of mechanism that allows filtering and ordering this information in a stable, internally coherent scheme. This is what the left hemisphere is in charge of: integrating the information into the previous image of self. What happens when a piece of information on the own behavior does not fit into the script? The left hemisphere disregards this information completely or distorts it so that it fits into the preexisting frame to maintain the stability. These everyday defense mechanisms, far from being adaptive defects, prevents the brain from being doomed to incoherence and lack
of direction due to the multiple combinatory possibilities of the scripts that can be written with the material collected by our experience. The problem is that one lies to oneself and to the others, but this is an efficient and affordable price compared with the coherence and stability that the whole system acquires. The adaption strategies used by both hemispheres are basically different (see Fig. 8.1). The task of the left hemisphere is to create a model, a belief system, and to fit every new experience into this system. When it finds information that goes against this belief system, it turns to denial: it represses and invents a story that allows maintaining the status quo. However, the right hemisphere’s strategy involves acting by calling this status quo into question, and searching for global inconsistencies. When the anomalous information reaches a certain threshold, the right hemisphere undertakes a global review of the model. In other words, the right hemisphere imposes a change of paradigm. This threshold is specific for each individual and depends on different aspects such as the features of personality or the type of experience. This would partly explain why after a stay in hospital for organic problems some individuals are able to accept their status as alcoholics, whereas others deny it at all costs, or why some individuals accept a relapse after the first time, while others need several relapses before they finally admit it. Table 8.2 depicts a conceptual model of the psychological, psychopathological, neuropsychological, and relational implications of the three concepts presented
TABLE 8.2 Distinctive Features of the Different Forms of Reality Distortion Typically Found in Addicted Individuals Features
Lie
Confabulation
Denial
Lack of awareness
Psychopathology
No
Yes
Yes/No
Yes
Intentionality
Yes
Yes/No
Yes
No
Consciousness
Yes
Yes/No
No
No
Type of knowledge
Explicit
Implicit
Implicit
Does not exist
Occurs within healthy individuals
Yes
No
Yes
No
Function
Deception
To make sense of a personal narrative
Self-deception
Don’t have
Premeditation
Yes
No
No
No
Access to the truth
Yes
No
Yes
No
Plausibility
Yes
Yes/No
Yes
Yes
Receptor
The other
Oneself/the other
Oneself/the other
Oneself/the other
Neuropsychological impairment
No
Yes
No
Yes
Knowledge
Knows that he/she knows Don’t know he/she doesn’t Don’t know he/she knows Don’t know he/she doesn’t know know
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in this section (lack of awareness, confabulation, denial, and lie).
SELF-AWARENESS, DENIAL, AND COGNITIVE DEFICITS We have seen that neuroscientific evidence links the symptoms of lack of awareness and denial with cognitive and emotional alterations derived from a dysfunction of the frontal-striatal circuits. In this section we shall review the neuropsychological studies that have addressed this issue in a direct manner. These studies can be classified according to three methodological approaches: (1) studies on the connection between measurement of denial level in addicted individuals and their performance in neuropsychological performance tasks; (2) studies on the concordance degree between the results of objective performance measurement and the individual’s insight of the own performance; and (3) studies on the concordance degree between the subjective information provided by addicted individuals and that provided by relevant informants regarding the problems derived from their addiction. Regarding the first approach, Rinn et al. studied the connection between clinical estimations of denial levels in a group of alcoholic individuals under treatment and their neuropsychological performance on memory and executive function tests. At the beginning of the treatment they identified specific objectives related to denial symptoms that alcoholic subjects had to achieve during the test. To obtain a quantitative measure of the individual’s denial level, they calculated the proportion of treatment objectives specifically for symptoms of denial that had not been completed. This measure was correlated with the performance indices from neuropsychological tests. The results showed that the degree of denial in addicted individuals significantly correlated to the impairment of the processing speed, memory, and executive function processes. In the light of these results, the challenge lies in finding the nature of the relationship between these cognitive functions and the mechanisms of denial. Regarding processing speed and denial, these data could show that the speed to understand information from outside is affected in addicted individuals. On a psychological level, this impairment produces a degradation of the input arriving at the brain. On an anatomical level, it reduces the connectivity between different regions (processing speed deficits have been associated to alterations in the white matter). Both levels are essential to create a coherent, unified global image of oneself and the surrounding world. As for the relationship between memory and denial, we must understand that
self-awareness is the capability of being conscious of a wide range of entities and facts, which generates a sense of individual perspective and space–time continuity. Therefore, it can be stated that we generate pulses of conscious experience for a goal, while generating an accompanying set of reactive autobiographical memories at the same time. Without these memories, we would not have a feeling of past or future, nor would a historic continuity exist (self-awareness). In other words, without conscious experience and memory, there is no self-awareness. At this level, we can locate confabulation phenomena oriented to reconstruct a sense of autobiographical coherence in addicted individuals. In fact, significant confabulation error rates have been observed in verbal memory tasks in psychostimulant users. Regarding the relationship between executive functions and denial, we consider that cold executive function processes can be more closely linked with the cognitive aspects implied in the insight, such as the updating of information about our own behavior or the cognitive flexibility that allows us change our rules and response patterns according to the feedback received. Therefore, they would be more closely related to the concept of knowledge of what is happening. However, there is a cognitive-emotional component necessary for the arising of insight, so that the subject can knock down his/her defense mechanisms (by saying defense, we do not adopt the dynamic vision, as we consider that each behavior has a brain correlate). In this sense, studies taking the Iowa Gambling Task as a paradigm highlight that addicted individuals have their decision-making processes affected, thus being guided by the immediate reinforcement and ignoring the long-term consequences of drug use. Furthermore, we know that this process is the result of the juxtaposition of cognitive processes and emotions, which takes place in the ventromedial prefrontal cortex, one of the regions that drug addiction most negatively effects. In this line, it is interesting that empathy of subjects with ventromedial affectation seems to be affected, which includes awareness of the potential damage inflicted to others. In addition, recent studies have proved the relationship between the activation of the ventromedial sector and self-knowledge. Both research lines offer a link between hot executive functions and self-awareness and insight. The second approach consisted on studying the correspondence between measures of objective performance and the individual’s insight on his/her own performance. Goldstein et al. have used a monetary effort attentional task (i.e. participants have to rapidly respond to get different amounts of money) in two groups: individuals with cocaine use disorders and healthy controls. The authors correlated participants’ performance in the task with subjective measures of motivation toward the
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monetary stake (a measure of state motivation). The results of these studies showed that, unlike healthy individuals, there was no correspondence between the subjective information provided by cocaine users about their level of motivation toward the monetary stakes and their actual performance in the task. Following a similar approach, several studies have shown that there is a certain level of dissociation between intention and action in addicted individuals. Two consecutive studies by Moeller et al. used a probabilistic learning task where participants (cocaine abusers and healthy individuals) had to choose between images with a pleasant, unpleasant, neutral or cocaine-related content. Additionally, subjective reports on the participants’ preferences in these choices were collected. The results of both studies showed that, contrary to what happened in healthy individuals, cocaine abusers showed significant inconsistency levels between the images chosen and their subjective preference reports. One of this study also showed that this inconsistency was especially obvious in current cocaine users, as opposed to abstinent users. Noticeably, within the abstinent consumer group, the highest inconsistency levels were observed in individuals with higher cocaine consumption in the month before the onset of treatment. Similarly, Verdejo-Garcı´a et al. used a self-regulation task where participants (cocaine-dependent and healthy individuals) had to discover on the go an implicit strategy that would allow them to improve their performance. Seventy percent of the consumers managed to correctly identify this strategy when they were debriefed about it. However, after analyzing their performance scores, these were significantly inferior to those of healthy individuals (i.e. despite having identified the optimal strategy, they had failed to implement it to optimize their performance). Finally, a last approach is based on the analysis of the concordance degree between the subjective information provided by addicted individuals and the one provided by relevant informants to them (e.g. close relatives or friends) regarding addiction-derived problems. Following this approach, the study by Verdejo-Garcı´a et al. examined the degree of awareness of substancedependent individuals about their potential behavioral problems linked to alterations of frontal-striatal circuits. These behavioral problems were assessed in the Frontal Systems Behavior Scale, which questions both the patient and an objective informant (typically, a relative) on symptoms of apathy, disinhibition, and behavioral disorganization. The analyses contrasted the patients’ scores with those of the relatives in two time moments: during drug use and during abstinence. The results showed that substance dependents reported significantly lower levels of apathetic and disorganized symptomatology compared with the reports of their relatives. Also, the severity degree of cocaine and alcohol use
correlated negatively with the level of discrepancy between addicts and relatives, which suggested an association between the severity of drug use problems and greater levels of lack of awareness on the implications of the addiction.
CONCLUSIONS AND CLINICAL IMPLICATIONS Deficits in the processes of awareness and denial of addiction and their consequences can have important implications in the treatment and rehabilitation of drug users. During active drug use, the deficits in these processes may be associated with reduced perception of need for treatment, for example, due to lack of insight about the problems or to a tendency to overestimate the own ability to control drug taking without help of others. Furthermore, during rehabilitation, lack of awareness on the own neuropsychological deficits may be associated with reductions in the motivation for treatment, lack of motivation and involvement in conducting the necessary tasks for the achievement of the intervention goals, or a higher feeling of control on the execution of risk behaviors like those entailing the contact with a drug-related context. For this reason, the inclusion of tools aiming to increase the individual’s self-awareness during the treatment of addiction could entail significant improvement in the recovering process. These measures could be used to reeducate the interoceptive system leading to an increase of the insight and the perception of body signals anticipating the craving for consuming drugs and potential relapses. Finally, based on the existing evidence and despite the great efforts made to distinguish the processes’ lack of awareness and denial, we still observe a certain overlap between both processes in the neuropsychological studies undertaken in addicted individuals. A more detailed research using specific measure tests of these processes in drug users could help obtain more enlightening information on the involvement of both phenomena in the course of addiction.
SEE ALSO An Evolutionary Perspective on Addiction, Cognitive Factors in Addictive Processes, Emotions and Addictive Processes, Metacognition in Substance Misuse
Glossary Confabulation implicit attempts to create an unreal autobiographical story to preserve a personal sense of coherence and continuity in our lives.
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Denial implicit suppression of cognitive or emotional information relevant to have adequate knowledge of oneself’s current status and of the implications of that status. Executive functions of higher order abilities involved in the generation, monitoring, and control of complex goal-directed behavior. They are critical to enact and integrate cognitive and emotional input necessary for adequate self-awareness. Intention–action dissociation lack of correspondence between explicit intention and the translation/implementation of that intention into actual behavior. Lack of awareness alterations in the access, processing, compiling, or monitoring of cognitive and emotional information critical to have adequate knowledge of oneself’s current status and of the implications of that status. Lie explicit omission of cognitive or emotional information relevant to understand oneself’s current status and make it understandable to others. This is done in an attempt to protect oneself from the consequences of truth. Neuropsychology science investigating the link between brain function and dysfunction and behavior (including cognitions, emotions, and acts). Self-awareness ability to perceive oneself in relatively objective terms, maintaining a sense of subjectivity. The construct encompasses the cognitive processes necessary for adequate self-knowledge, the emotional processes necessary to understand the implications of the current status for oneself and others, and the integration of cognition and emotion to adjust behavior to one’s and others’ needs.
Further Reading Duffy, J.D., 1995. The neurology of alcohol denial: implications for assessment and treatment. Canadian Journal of Psychiatry 40, 257–263. Ekman, P., 1975. Unmasking the Face: Guide to Recognizing Emotions from Facial Clues. Prentice Hall, Englewood Cliffs, N.J. Goldstein, R.Z., Parvaz, M.A., Maloney, T., Alia-Klein, N., Woicik, P.A., Telang, F., Wang, G.J., Volkow, N.D., 2008. Compromised sensitivity to monetary reward in current cocaine users: and ERP study. Psychophysiology 45, 705–713. Goldstein, R.Z., Craig, A.D., Bechara, A., Garavan, H., Childress, A.R., Paulus, M.P., Volkow, N.D., 2009. The neurocircuitry of impaired insight in drug addictions. Trends in Cognitive Sciences 13, 372–380. Langer, K.G., Padrone, F.J., 1992. Psychotherapeutic treatment of awareness in acute rehabilitation of traumatic brain injury. Neuropsychological Rehabilitation 2, 59–70.
LeDoux, J., Wilson, D.H., Gazzaniga, M., 1977. A divided mind. Annals of Neurology 2, 417–421. Moeller, S.J., Maloney, T., Parvaz, M.A., Dunning, J.P., Alia-Klein, N., Hajcak, G., Telang, F., Wang, G.J., Volkow, N.D., Goldstein, R.Z., 2009. Enhanced choice for viewing cocaine pictures in cocaine addiction. Biological Psychiatry 66, 169–176. Moeller, S.J., Maloney, T., Parvaz, M.A., Alia-Klein, N., Woicik, P.A., Telang, F., Wang, G.J., Volkows, N.D., Goldstein, R.Z., 2010. Impaired insight in cocaine addiction: laboratory evidence and effects on cocaine-seeking behaviour. Brain 133, 1483–1484. Prigatano, G., Weintein, E.A., 1996. Edwin A. Weinstein’s contributions to neuropsychological rehabilitation. Neuropsychological Rehabilitation 6, 305–326. Rinn, W., Desai, N., Rosenblatt, H., Gastfriend, D.R., 2002. Addiction denial and cognitive dysfunction: a preliminary investigation. The Journal of Neuropsychiatry and Clinical Neuroscience 14, 52–57. Stuss, D.T., Alexander, M.P., 2000. Executive functions and the frontal lobes: a conceptual view. Psychological Research 63, 289–298. Stuss, D.T., Levine, B., 2002. Adult clinical neuropsychology: lessons from studies of the frontal lobes. Annual Review of Psychology 53, 401–433. Tomasi, D., Zhang, L., Cottone, L.A., Maloney, T., Telang, F., Caparelli, E.C., Chang, L., Ernst, T., Samaras, D., Squires, N.K., Volkow, N.D., 2007. Is decreased prefrontal cortical sensitivity to monetary reward associated with impaired motivation and selfcontrol in cocaine addiction? American Journal of Psychiatry 164, 43–51. Verdejo-Garcia, A., Rivas-Pe´rez, C., Vilar-Lo´pez, R., Pe´rez-Garcı´a, M., 2007. Strategic self-regulation, decision-making and emotion processing in poly-substance abusers in their first year of abstinence. Drug and Alcohol Dependence 86, 139–146. Verdejo-Garcı´a, A., Pe´rez-Garcı´a, M., 2008. Substance abusers’ selfawareness of the neurobehavioral consequences of addiction. Psychiatry Research 158, 172–180.
Relevant Websites http://www.candaceplattor.com/articles/Denial_and_Addiction. pdf – Definition and types of denial. http://www.tgorski.com/clin_mod/dmc/dmc.htm – Denial management counseling, T. Gorski. http://www.proyectohombrenavarra.org/07documentacion/libroilorea .pdf – Brain and addiction, J. Tirapu.
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8 Denial and Lack of Awareness in Substance Dependence: Insights from the Neuropsychology of Addiction A. Verdejo-Garcı´a*, M.J. Fernandez-Serrano$, J. Tirapu-Ustarroz** *
Institute of Neuroscience F. Olo´riz, Universidad de Granada, Granada, Spain, $Department of Psychology, Universidad de Jae´n, Jae´n, Spain, **Clı´nica Ubarmin, Egu¨e´s-Navarra, Spain
O U T L I N E Introduction
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About Lie Self-Awareness, Denial, and Cognitive Deficits
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Conclusions and Clinical Implications
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INTRODUCTION
Continuous exposure to drug use turns these impulsive behaviors into habits, that is, impulsivity gives way to compulsion, thus consolidating motor programs that go off automatically in the presence or anticipation of drug-related signals. Repeated consumption also provokes important changes in the interoceptive and emotional systems. Recent studies highlight the role that detection of body signals related to drug-taking experiences plays in the generation of emotional states leading to drug-seeking behavior, such as craving. In addition, a persistent sensitization of the stress systems takes place and the drug-seeking behavior rockets in an attempt to rebalance the body’s hedonic tone. Alongside this adaptation of the motivational and affective systems, addiction is associated with a deterioration of the executive control mechanisms, which depend on the functioning of the prefrontal cortex. The dysfunction of executive mechanisms leads to alterations of processes which are considered of a more cognitive nature, such as the ability to update and monitor multiple sources of information (cognitive, affective, and motivational) aiming to design plans and reach
Substance use and dependence is characterized by a difficulty to control consumption and a tendency to persistence despite its increasing adverse consequences (DSM-IV, CIE-10). Current neuropsychological models conceive addiction as a neuroadaptive process leading to significant alterations in the frontal-striatal circuits, including several sections of the prefrontal cortex (orbitofrontal, dorsolateral, and medial), limbic and paralimbic regions (amygdala, hippocampus, insula), and basal ganglia. Alterations in these circuits affect the activity of the motivational, emotional, and executive control systems. Dysfunction of motivational systems is made evident by the overestimation of the reinforcing, adaptive value of drug-related stimuli and the underestimation of the value of other natural reinforcers, fundamental to our survival. This motivational bias promotes the development of impulsive behaviors, which are fostered by the expectation of immediate reinforcement (drug use–related), whereas little consideration is given to its potential, long-term consequences. Principles of Addiction, Volume 1 http://dx.doi.org/10.1016/B978-0-12-398336-7.00008-5
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goals. In addition, it hinders the ability to inhibit and effectively switch response patterns according to the changing demands in the environment, as well as the capability for making adaptive decisions that guarantee both our survival and our survival quality. The notion of lack of awareness of addiction and its consequences is inherent in a number of the neuropsychological dysfunctions reviewed above. Neuroadaptations in interoceptive, motivational, and affective systems may contribute to a persisting attentional bias on drug-related needs that prevents considering other homeostatic signals. The results of recent neuroimaging studies show that dysfunction of the insula (a key region for processing and integrating interoceptive signals) may underlie the difficulties of addicted individuals to gain access to the emotional signals that are necessary to realize the implications of the disorder and develop alternative behaviors. In addition, the consolidation of an impulsive response pattern implies a lack of consideration of the input associated to delayed information, which would include most of the negative consequences of addiction. In this sense, we know that the ability to imagine future emotional events is related to the functioning of the medial orbitofrontal cortex, one of the most affected regions by addiction. On the other hand, once the addictive process is established, many processes oriented to drug seeking and taking (e.g. programming of motor habits) may operate in a sophisticated manner without full conscious supervision or control. Finally, dysfunction of executive mechanisms affects mainly the individual’s ability to maintain the correspondence between intention and action and to compile all necessary information to become aware of his/her deficits and their repercussions on the family milieu and social environment. To sum up, to be aware of the symptoms and repercussions of any disorder, we need to have access to all relevant information (internal and external) and be able to properly compile and monitor this information to understand its implications and use it to establish goals and implement change-oriented behaviors. In addiction, however, we find that many processes underlying these capacities are significantly deteriorated. In these cases we may talk about lack of awareness – but not denial as a meta-cognitive deficit resulting from deterioration of information processing and integration at different levels. This deterioration is linked to the dysfunction of frontal-striatal circuits involved in addiction. The concept of denial implies an implicit knowledge that can be accessed depending on the state of the organism in a particular situation, as well as an elaboration process aimed to minimize or suppress this input. Parallel neuroadaptive processes typical of addiction can also help understand this phenomenon. In their extreme form, denial processes could be compared
with the symptoms of confabulation observed in neurological patients. Symptoms of confabulation are common in patients with damage in the medial orbitofrontal cortex, one of the key brain regions both in selfreferential processes and in addiction. There is evidence that confabulations in these patients are related to (not necessarily conscious) efforts to maintain a positive self-concept or a self-referential sense of coherence, thus building a valid argumentation to maintain a status quo that will not put their own identity at risk. These confabulation mechanisms oriented to maintain a status quo could help explain the phenomenon of denial in addicted individuals. On the other hand, partial access to input regarding disorder implications may exacerbate the reactivity of the stress systems, leading to intense discomfort and undermining the individual’s selfefficacy expectations on his/her capacity to cope with the problem. This unbearable rise in stress levels makes the individual react by expelling this information from his/her conflict resolution system. These psychological processes would depend on the dialog between the brain regions responsible for the motivation and conflict (anterior cingulate cortex) and the neuroendocrine systems regulating the response to stress (hypothalamic– pituitary–adrenal axis), which are persistently altered in the addictive processes. Other authors have also highlighted the role of the cross-talk between the cognitive styles of both brain hemispheres (right hemisphere, specializing in processing novelty vs. left hemisphere, specializing in contextualizing information according to preestablished patterns) as a substrate of these dissociations. Finally, a milder form of denial may result from the predominance of motivational resources driving drug seeking and taking on those resources in charge of motivation to change. In these cases patients would be partially aware of their disorder and the need for change, but they would tend to minimize or defer it. Classical models on stages of change claim that denial would be a process inherent to the precontemplation stage. In this stage the individual considers the possibility of changing his/her drug use behavior but may deny the problem in different manners, including resignation due to lack of selfefficacy necessary to produce change, or deferral of the change. In agreement with this notion, recent studies indicate that drug users present decision styles characterized by procrastination. In sum, we understand lack of awareness and denial are two separable neuropsychological processes. However, we believe that they both have underlying neuropsychological (motivational, emotional, and meta-cognitive) alterations related to addiction-related neuroadaptations in frontal-striatal circuits. In the following sections we shall: (1) define a neuroscientific conceptual framework to understand the phenomena
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of lack of awareness, denial, and lie in addiction; (2) describe the relationship between neuropsychological processes and symptoms of anosognosia and denial; and (3) review the empirical studies having dealt with this phenomenon from different approaches over the last decade.
AWARENESS, LIE, AND DENIAL IN ADDICTION: A NEUROSCIENTIFIC APPROACH Self-Awareness Being conscious and the conscious experience may be explained by models based on the more proximal brain function, related to general neuronal action patterns. However, we all agree that awareness is more than that. When we say that someone is not aware of something, we are referring not only to tacit knowledge, but also to other relevant aspects, such as the implications of that knowledge. In the case of addiction, when we talk about lack of awareness, we refer not only to aspects such as insight of the cognitive deficits associated with drug use, but also to awareness itself about suffering this disorder. The latter would be more closely linked to the concepts of self-awareness and self-concept, which use defense or self-protection mechanisms to avoid the emotional consequences of accepting that one suffers a disorder. Self-awareness has been defined as a human tribute that allows not only awareness of the self but also awareness of one’s position in his/her social environment. In a hierarchical organization of mental functions, the ability of self-awareness would be in the vertex of the pyramid, since its function is to control one’s own mental activity, representing current experiences in relation to previous ones, using acquired knowledge to solve new situations, or guiding decision making for the future. According to Prigatano, selfawareness is the ability to perceive oneself in relatively objective terms, maintaining a sense of subjectivity. This aspect of self-awareness implies a cognitive process, as well as an emotional state, and the integration of both. The critical neural system for self-awareness is located in the prefrontal cortices, whose neuroanatomic position favors this purpose because (1) they receive signals stemming from all sensory regions where conscious experiences are formed (including images making part of our thoughts); (2) they receive signals from somatosensory cortices representing past and current body states; (3) they receive signals from bioregulatory sectors of the brain, among which neurotransmitters of the brainstem and basal prosencephalon, as well as the amygdala, the anterior cingulate, and the
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hypothalamus; and (4) they categorize the situations that affect the body, that is, they classify any contingencies in our life experience. Therefore, the prefrontal cortex is often a convergence zone that works as a deposit of dispositional representations for properly categorized, unique contingencies of our life experience. In this sense, it seems evident that, to exist, selfawareness needs information from signals coming from both outside of the self and our thoughts (which are also images). Also, it needs to have access to previously categorized information (the categorization criteria are probably based on the emotional value of the experiences). At this point, we create representations that become unique dispositions, as they are based on our life experience, which is also unique. From this point of view, and according to Stuss and colleagues, the alterations of awareness related to lesions in the prefrontal cortex have some peculiarities that should be taken into account: (1) these alterations are connected to the self and become evident generally in behavioral rather than cognitive functioning; (2) these alterations may occur irrespective of any cognitive or sensory deficits, even with an intact IQ; (3) executive functions (i.e. higher order abilities involved in the generation and control of goal-directed behavior) are important, since they are more specifically related to prefrontal systems and their damage may be linked with the alteration in awareness of deficits in behavioral functioning; (4) there may be a fractioning of awareness in relation to specific connections between the prefrontal cortex and other specific regions; (5) self-awareness is more than mere knowledge, it is the ability to reflect on the implications of this knowledge; and (6) selfawareness does not only refer to the past and the present, but it also projects to the future. In this sense, we would depict awareness not only as knowledge, since knowledge does not have implications if devoid of emotional valence. In the case of addiction, structural and functional alterations in the prefrontal cortex have been described by several neuroimaging studies in abusers of a number of drugs. Furthermore, the main corollaries of prefrontal cortex–related awareness alterations largely overlap with the neuropsychological alterations described in addicted individuals. Specifically, addicted individuals: (1) show a wide range of behavioral alterations associated with the functioning of the circuits connecting the prefrontal cortex with subcortical regions and basal ganglia (including symptoms of apathy, disinhibition, and behavioral disorganization); (2) show important alterations in executive functions, even in the presence of normal, general cognitive functions and IQ; (3) have problems to think about the consequences that these and other drug use-related alterations bring about in their daily functioning and their family milieu and social environment; and (4) show difficulties
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in associating cognitive scenarios with appropriate emotional states, especially when it comes to anticipate emotional consequences associated with future events. This more neuropsychological approach claims that there are different forms of deteriorated awareness, depending on the brain systems suffering the damage or dysfunction. In Fig. 8.1 we present a schematic representation of the different brain systems linked to awareness-related deficits. In this line, neuroscientific models have proposed in a generic manner that bilateral lesions of the frontal cortex are specifically associated with the lack of awareness on social behavior and executive functions, and with self-awareness as a whole. Clinical experience shows that there is a particular type of awareness for each knowledge module, which is fed by updated information from that particular module, whose goal is to guarantee the best adjustment of the individual. In this sense it seems that this
awareness for each specific area is affected when the brain damage affects the function and its awareness locus. We must take into account that addiction-related brain alterations may interfere with the neural substrate of self-awareness. Therefore, if a prejudicial drug use pattern produces a deficit in the cognitive, emotional, and behavioral sphere that the subject is not aware of, this lesion affects both the locus of the relative processes and the locus of their awareness. In other words, it would affect the cognitive function, the emotional sphere or its behavioral patterns, as well as the metacognition of the cognitive, emotional, or behavioral function. We could state, in a graphic manner, that the individual does not know that he/she does not know and this first aspect would make reference to concepts such as change of personality, suffering provoked to others, empathy, etc. In addition, awareness for a specific knowledge module may be affected by the degradation
FIGURE 8.1 Schematic representation of the main brain regions supporting awareness and denial-related deficits in substance-dependent individuals. 1. Right dorsolateral prefrontal cortex (Panel A) and right medial orbitofrontal cortex (Panel B), along with insula (Panel C), are involved in deficits of lack of awareness. 2. Interhemispheric right-left cross-talk or connections between anterior cingulate cortex and stress systems stemming from hypothalamus mediate processes of denial (Panel D). 3. Medial/lateral orbitofrontal cortices and frontal pole are key structures for the emergence of confabulations (Panels A and B). 4. Dorsolateral prefrontal cortex and dorsal anterior cingulate control are necessary systems for lie (Panels A and D).
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of feedback of its response or output or because the internal representation of the cognitive processes is also affected as a result of the brain impairment. For example, drug use may affect attentional mechanisms, which would lead to a degradation of the information sent to the brain. Thus, the subject cannot be aware due to the affectation of input mechanisms (Wernicke’s aphasia may be the clearest example in neurological patients). In other words, we find that drug use leads to the affectation of cognitive, emotional, and behavioral functions, as well as the affectation of cognitive, emotional, and behavioral mechanisms implied in selfknowledge and self-awareness.
Denial Some studies have proposed the existence of different kinds of alteration of awareness of one deficit according to the three basic levels of information processing: information collection, neuropsychological, and emotional. Thus, the lack of awareness itself would be the result of the patient not receiving information or this information being degraded. Also, it is possible that the patient does not understand the meaning of the information (e.g. it has been proved that alcoholic people have difficulties in processing faces expressing some basic emotions, such as sadness, relevant to understand damage inflicted to others). Regarding the level of implication of this information, the subject cannot take the self as an object or understand the implication of the deficit.
Additionally, the arousal level for awareness may also be poor (a phenomenon frequently observed in benzodiazepine or opiate addicts). In this case, the deficit occurs at the information processing and access level. However, there are other phenomena related to the lack of awareness of different nature and characteristics. The phenomenon of minimization is characterized by the fact that the patient cannot understand or extract his/ her own consequences and/or implications from the information. On an emotional level, the patient knows but cannot stand the effect of the information, thus reducing it to tolerance levels. Finally, in the case of denial, the patient has an implicit knowledge about the problem, but he/she cannot believe the information, which is too stressful, and expels it from his/her aware experience (see Table 8.1). On the other hand, studies have shown that denial observed in some chronic alcohol abusers does not necessarily need to be explained as a consequence of a maladaptive defense of the self, but as a manifestation of the neurotoxic effects of alcohol. Prigatano has investigated the alterations in awareness of deficits in patients suffering brain damage, based on Weinstein’s pioneer studies in the 1950s. Weinstein reckoned that the way that patients adapt and symbolically represent (a term with dynamic connotations) their deficits is determined by a series of factors, such as: (1) the type, severity, and location of brain damage; (2) the nature of the incapability; (3) the meaning that this deficit may have in terms of premorbid values and
TABLE 8.1 Nature of the Consciousness Problem Considering Three Possible Levels of Information Processing Nature of the consciousness problem
Level 1 e Information
Level 2 e Implications (Neuropsychological)
Level 3 e Integration (Emotional)
Lack of awareness
- The individual cannot access the information. - The individual has not enough cognitive resources to understand the meaning of the information. - Main symptom is anosognosia.
- The individual cannot take the “self” as an object. - The individual cannot understand the information. - The individual cannot retain or remember the information. - Insufficient arousal for full conscious experience.
- No strong emotional implications.
Minimization
- No alterations at this level.
- The individual cannot extract from the information its consequences and implications.
- The individual knows but cannot tolerate the effect of the information, thus reducing it to tolerance levels.
Denial
- No alterations at this level.
- No major neuropsychological alterations although sensitization of stress systems and cross-talk between conflict control and stress systems or right vs. left hemispheres cognitive styles may contribute.
- The individual cannot believe the information, it’s too stressing and therefore it is expelled from conscious experience.
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experiences; and (4) the context in which the behavior is elicited and observed. According to Weinstein, denial must be understood as a loss of insight and is related to confabulation, lie, or symbolic disorientation. Also, Weinstein exposed the importance of premorbid personality factors to understand the mechanisms of denial, as well as the presence of implicit knowledge. In this sense, the mechanisms of denial are adaptive as long as they represent and explain the patient’s incapability, giving it a sense of reality. In this line, Prigatano claims that denial of a deficit is due to several factors affecting superior levels of brain integration. In this sense, the cognitive capability of patients with brain dysfunction may be affected in evaluating the feedback about their functional limitations received from the environment. In addition, and despite receiving information about their own problems and limitations from the environmental feedback, they persist in maintaining a somewhat indifferent attitude toward this information. In fact, recent studies seem to prove that the insula plays an important role in the awareness of affective states, perhaps because the information on these affective states is produced by the brain mapping of associated body states. These connections may contribute to explain why in addiction profoundly altered body states and behavioral problems do not lead to full recognition of the disorder (see Fig. 8.1).
About Lie Lie is a constant in approaching the phenomenon of drug addictions, contaminating very often the therapeutic relationship with patients. Lie does not refer to the consumption of toxics alone; deception goes beyond that and has to do with the perception of the problem. In fact, it is surprising that a patient denies having problems with his/her partner, children, or at work due to alcohol use (alteration of central awareness), and even more that he/she can create an unreal autobiographic story, where there seems to be no problem whatsoever (alteration of extended awareness). In therapeutic intervention, it is frequent to find patients that deceive or lie. In fact, distrust in patients’ claims is the ultimate cause of taking urine samples for analysis. The first question is: why do patients lie? The response is simple: what do they win by telling the truth? Cognitive psychology suggests that a basic stone for the treatment of drug addicts is anticipation of the consequences of their behavior, so that they will behave accordingly. This leads to a second question: to what point do they need to anticipate? The variable time is essential in brain functioning: if the anticipated consequences are negative in the short term, behavior inhibits the truth. It is a brain functioning mechanism: my brain has an image of what I am and how I am; a self-
protecting image that compares data coming from experience to expel them if they contradict the image of myself, thus maintaining my status quo. There are patients that obviously know that they are lying, but they do it to protect themselves from the consequences of truth. When a subject generates mental images of the consequences of being honest, these images generate a negative emotion that inhibits the behavior, thus lie having an adaptive preservation value. Actually, it can be claimed that awareness is a human tribute that allows realizing the own reality and position in the social environment. Lie can, therefore, maintain the concept of reality and social status. In this sense, it can be claimed that the lack of awareness of a problem has the invented truth as a basic pillar to convert subjectivity into objectivity, so that this subjective, unique, private interpretation of my reality will be perceived by others in the way I perceive it. This will allow my maintaining the situation and more importantly the image I have of myself. Trivers has suggested an ingenious explanation of the evolution of self-deception: in everyday life there are many situations where we need to lie. In this regard, researchers like Ekman have proved that liars always give themselves away with a somewhat feigned smile, an expression of tension, or a false tone of voice that can be detected by others. This is because the limbic system (involuntary and prone to tell the truth) controls the spontaneous expressions, whereas the facial expressions we make when we lie are controlled by the cortex (not only responsible for the voluntary control, but also the place where lies are invented). For Trivers, this problem has a solution: to effectively lie to another person, it is necessary to lie to oneself first. If we believe that the thing we are saying is true, our expressions will be real, with no trace of deception. However, this statement incurs into an internal contradiction, since it contradicts the proposal of self-deception, which implies that one can have access to the truth at any time; otherwise, self-deception would no longer be adaptive. Ramachandran proposes a way to avoid this problem and states that a belief is not necessarily unitary: it is possible that self-deception is located in the left hemisphere, whereas the right hemisphere continues to know the truth. For this author, the key for self-deception lies in the working division between both brain hemispheres and our need to create a feeling of coherence and continuity in our lives. It is well known that the brain consists of two symmetrical halves, each of which specializes in different mental capabilities; the most noticeable brain asymmetry is related to language. Alongside these known function divisions, Ramachandran suggests the existence of an even more essential difference between the cognitive styles of both hemispheres, which can help explain the modalities of denial and lack of awareness. In this regard, Gazzaniga’s
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research on split brain is most revealing. This author has studied a series of patients with a disconnection between both hemispheres, which allows us to know the information stored by each of them separately. In Case P.S., one of the paradigmatic cases reported, the individual’s left hemisphere is asked what he wants to do after finishing school, the answer being: I want to be a draftsman. However, when the right hemisphere is asked the same question, the answer was: automobile racer. This case, like others in the literature, proves that both brain hemispheres live different realities and suggests that everyone can have a mute brain inside the head with a reality and a perception of oneself very different to what we daily believe we are. In any moment of life, the brain can feel overwhelmed by a continuous information cascade that must be integrated into a coherent perspective of the own image and the image that others expect from oneself. To generate coherent actions or to maintain a given status quo, the brain must have a type of mechanism that allows filtering and ordering this information in a stable, internally coherent scheme. This is what the left hemisphere is in charge of: integrating the information into the previous image of self. What happens when a piece of information on the own behavior does not fit into the script? The left hemisphere disregards this information completely or distorts it so that it fits into the preexisting frame to maintain the stability. These everyday defense mechanisms, far from being adaptive defects, prevents the brain from being doomed to incoherence and lack
of direction due to the multiple combinatory possibilities of the scripts that can be written with the material collected by our experience. The problem is that one lies to oneself and to the others, but this is an efficient and affordable price compared with the coherence and stability that the whole system acquires. The adaption strategies used by both hemispheres are basically different (see Fig. 8.1). The task of the left hemisphere is to create a model, a belief system, and to fit every new experience into this system. When it finds information that goes against this belief system, it turns to denial: it represses and invents a story that allows maintaining the status quo. However, the right hemisphere’s strategy involves acting by calling this status quo into question, and searching for global inconsistencies. When the anomalous information reaches a certain threshold, the right hemisphere undertakes a global review of the model. In other words, the right hemisphere imposes a change of paradigm. This threshold is specific for each individual and depends on different aspects such as the features of personality or the type of experience. This would partly explain why after a stay in hospital for organic problems some individuals are able to accept their status as alcoholics, whereas others deny it at all costs, or why some individuals accept a relapse after the first time, while others need several relapses before they finally admit it. Table 8.2 depicts a conceptual model of the psychological, psychopathological, neuropsychological, and relational implications of the three concepts presented
TABLE 8.2 Distinctive Features of the Different Forms of Reality Distortion Typically Found in Addicted Individuals Features
Lie
Confabulation
Denial
Lack of awareness
Psychopathology
No
Yes
Yes/No
Yes
Intentionality
Yes
Yes/No
Yes
No
Consciousness
Yes
Yes/No
No
No
Type of knowledge
Explicit
Implicit
Implicit
Does not exist
Occurs within healthy individuals
Yes
No
Yes
No
Function
Deception
To make sense of a personal narrative
Self-deception
Don’t have
Premeditation
Yes
No
No
No
Access to the truth
Yes
No
Yes
No
Plausibility
Yes
Yes/No
Yes
Yes
Receptor
The other
Oneself/the other
Oneself/the other
Oneself/the other
Neuropsychological impairment
No
Yes
No
Yes
Knowledge
Knows that he/she knows Don’t know he/she doesn’t Don’t know he/she knows Don’t know he/she doesn’t know know
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in this section (lack of awareness, confabulation, denial, and lie).
SELF-AWARENESS, DENIAL, AND COGNITIVE DEFICITS We have seen that neuroscientific evidence links the symptoms of lack of awareness and denial with cognitive and emotional alterations derived from a dysfunction of the frontal-striatal circuits. In this section we shall review the neuropsychological studies that have addressed this issue in a direct manner. These studies can be classified according to three methodological approaches: (1) studies on the connection between measurement of denial level in addicted individuals and their performance in neuropsychological performance tasks; (2) studies on the concordance degree between the results of objective performance measurement and the individual’s insight of the own performance; and (3) studies on the concordance degree between the subjective information provided by addicted individuals and that provided by relevant informants regarding the problems derived from their addiction. Regarding the first approach, Rinn et al. studied the connection between clinical estimations of denial levels in a group of alcoholic individuals under treatment and their neuropsychological performance on memory and executive function tests. At the beginning of the treatment they identified specific objectives related to denial symptoms that alcoholic subjects had to achieve during the test. To obtain a quantitative measure of the individual’s denial level, they calculated the proportion of treatment objectives specifically for symptoms of denial that had not been completed. This measure was correlated with the performance indices from neuropsychological tests. The results showed that the degree of denial in addicted individuals significantly correlated to the impairment of the processing speed, memory, and executive function processes. In the light of these results, the challenge lies in finding the nature of the relationship between these cognitive functions and the mechanisms of denial. Regarding processing speed and denial, these data could show that the speed to understand information from outside is affected in addicted individuals. On a psychological level, this impairment produces a degradation of the input arriving at the brain. On an anatomical level, it reduces the connectivity between different regions (processing speed deficits have been associated to alterations in the white matter). Both levels are essential to create a coherent, unified global image of oneself and the surrounding world. As for the relationship between memory and denial, we must understand that
self-awareness is the capability of being conscious of a wide range of entities and facts, which generates a sense of individual perspective and space–time continuity. Therefore, it can be stated that we generate pulses of conscious experience for a goal, while generating an accompanying set of reactive autobiographical memories at the same time. Without these memories, we would not have a feeling of past or future, nor would a historic continuity exist (self-awareness). In other words, without conscious experience and memory, there is no self-awareness. At this level, we can locate confabulation phenomena oriented to reconstruct a sense of autobiographical coherence in addicted individuals. In fact, significant confabulation error rates have been observed in verbal memory tasks in psychostimulant users. Regarding the relationship between executive functions and denial, we consider that cold executive function processes can be more closely linked with the cognitive aspects implied in the insight, such as the updating of information about our own behavior or the cognitive flexibility that allows us change our rules and response patterns according to the feedback received. Therefore, they would be more closely related to the concept of knowledge of what is happening. However, there is a cognitive-emotional component necessary for the arising of insight, so that the subject can knock down his/her defense mechanisms (by saying defense, we do not adopt the dynamic vision, as we consider that each behavior has a brain correlate). In this sense, studies taking the Iowa Gambling Task as a paradigm highlight that addicted individuals have their decision-making processes affected, thus being guided by the immediate reinforcement and ignoring the long-term consequences of drug use. Furthermore, we know that this process is the result of the juxtaposition of cognitive processes and emotions, which takes place in the ventromedial prefrontal cortex, one of the regions that drug addiction most negatively effects. In this line, it is interesting that empathy of subjects with ventromedial affectation seems to be affected, which includes awareness of the potential damage inflicted to others. In addition, recent studies have proved the relationship between the activation of the ventromedial sector and self-knowledge. Both research lines offer a link between hot executive functions and self-awareness and insight. The second approach consisted on studying the correspondence between measures of objective performance and the individual’s insight on his/her own performance. Goldstein et al. have used a monetary effort attentional task (i.e. participants have to rapidly respond to get different amounts of money) in two groups: individuals with cocaine use disorders and healthy controls. The authors correlated participants’ performance in the task with subjective measures of motivation toward the
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CONCLUSIONS AND CLINICAL IMPLICATIONS
monetary stake (a measure of state motivation). The results of these studies showed that, unlike healthy individuals, there was no correspondence between the subjective information provided by cocaine users about their level of motivation toward the monetary stakes and their actual performance in the task. Following a similar approach, several studies have shown that there is a certain level of dissociation between intention and action in addicted individuals. Two consecutive studies by Moeller et al. used a probabilistic learning task where participants (cocaine abusers and healthy individuals) had to choose between images with a pleasant, unpleasant, neutral or cocaine-related content. Additionally, subjective reports on the participants’ preferences in these choices were collected. The results of both studies showed that, contrary to what happened in healthy individuals, cocaine abusers showed significant inconsistency levels between the images chosen and their subjective preference reports. One of this study also showed that this inconsistency was especially obvious in current cocaine users, as opposed to abstinent users. Noticeably, within the abstinent consumer group, the highest inconsistency levels were observed in individuals with higher cocaine consumption in the month before the onset of treatment. Similarly, Verdejo-Garcı´a et al. used a self-regulation task where participants (cocaine-dependent and healthy individuals) had to discover on the go an implicit strategy that would allow them to improve their performance. Seventy percent of the consumers managed to correctly identify this strategy when they were debriefed about it. However, after analyzing their performance scores, these were significantly inferior to those of healthy individuals (i.e. despite having identified the optimal strategy, they had failed to implement it to optimize their performance). Finally, a last approach is based on the analysis of the concordance degree between the subjective information provided by addicted individuals and the one provided by relevant informants to them (e.g. close relatives or friends) regarding addiction-derived problems. Following this approach, the study by Verdejo-Garcı´a et al. examined the degree of awareness of substancedependent individuals about their potential behavioral problems linked to alterations of frontal-striatal circuits. These behavioral problems were assessed in the Frontal Systems Behavior Scale, which questions both the patient and an objective informant (typically, a relative) on symptoms of apathy, disinhibition, and behavioral disorganization. The analyses contrasted the patients’ scores with those of the relatives in two time moments: during drug use and during abstinence. The results showed that substance dependents reported significantly lower levels of apathetic and disorganized symptomatology compared with the reports of their relatives. Also, the severity degree of cocaine and alcohol use
correlated negatively with the level of discrepancy between addicts and relatives, which suggested an association between the severity of drug use problems and greater levels of lack of awareness on the implications of the addiction.
CONCLUSIONS AND CLINICAL IMPLICATIONS Deficits in the processes of awareness and denial of addiction and their consequences can have important implications in the treatment and rehabilitation of drug users. During active drug use, the deficits in these processes may be associated with reduced perception of need for treatment, for example, due to lack of insight about the problems or to a tendency to overestimate the own ability to control drug taking without help of others. Furthermore, during rehabilitation, lack of awareness on the own neuropsychological deficits may be associated with reductions in the motivation for treatment, lack of motivation and involvement in conducting the necessary tasks for the achievement of the intervention goals, or a higher feeling of control on the execution of risk behaviors like those entailing the contact with a drug-related context. For this reason, the inclusion of tools aiming to increase the individual’s self-awareness during the treatment of addiction could entail significant improvement in the recovering process. These measures could be used to reeducate the interoceptive system leading to an increase of the insight and the perception of body signals anticipating the craving for consuming drugs and potential relapses. Finally, based on the existing evidence and despite the great efforts made to distinguish the processes’ lack of awareness and denial, we still observe a certain overlap between both processes in the neuropsychological studies undertaken in addicted individuals. A more detailed research using specific measure tests of these processes in drug users could help obtain more enlightening information on the involvement of both phenomena in the course of addiction.
SEE ALSO An Evolutionary Perspective on Addiction, Cognitive Factors in Addictive Processes, Emotions and Addictive Processes, Metacognition in Substance Misuse
Glossary Confabulation implicit attempts to create an unreal autobiographical story to preserve a personal sense of coherence and continuity in our lives.
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Denial implicit suppression of cognitive or emotional information relevant to have adequate knowledge of oneself’s current status and of the implications of that status. Executive functions of higher order abilities involved in the generation, monitoring, and control of complex goal-directed behavior. They are critical to enact and integrate cognitive and emotional input necessary for adequate self-awareness. Intention–action dissociation lack of correspondence between explicit intention and the translation/implementation of that intention into actual behavior. Lack of awareness alterations in the access, processing, compiling, or monitoring of cognitive and emotional information critical to have adequate knowledge of oneself’s current status and of the implications of that status. Lie explicit omission of cognitive or emotional information relevant to understand oneself’s current status and make it understandable to others. This is done in an attempt to protect oneself from the consequences of truth. Neuropsychology science investigating the link between brain function and dysfunction and behavior (including cognitions, emotions, and acts). Self-awareness ability to perceive oneself in relatively objective terms, maintaining a sense of subjectivity. The construct encompasses the cognitive processes necessary for adequate self-knowledge, the emotional processes necessary to understand the implications of the current status for oneself and others, and the integration of cognition and emotion to adjust behavior to one’s and others’ needs.
Further Reading Duffy, J.D., 1995. The neurology of alcohol denial: implications for assessment and treatment. Canadian Journal of Psychiatry 40, 257–263. Ekman, P., 1975. Unmasking the Face: Guide to Recognizing Emotions from Facial Clues. Prentice Hall, Englewood Cliffs, N.J. Goldstein, R.Z., Parvaz, M.A., Maloney, T., Alia-Klein, N., Woicik, P.A., Telang, F., Wang, G.J., Volkow, N.D., 2008. Compromised sensitivity to monetary reward in current cocaine users: and ERP study. Psychophysiology 45, 705–713. Goldstein, R.Z., Craig, A.D., Bechara, A., Garavan, H., Childress, A.R., Paulus, M.P., Volkow, N.D., 2009. The neurocircuitry of impaired insight in drug addictions. Trends in Cognitive Sciences 13, 372–380. Langer, K.G., Padrone, F.J., 1992. Psychotherapeutic treatment of awareness in acute rehabilitation of traumatic brain injury. Neuropsychological Rehabilitation 2, 59–70.
LeDoux, J., Wilson, D.H., Gazzaniga, M., 1977. A divided mind. Annals of Neurology 2, 417–421. Moeller, S.J., Maloney, T., Parvaz, M.A., Dunning, J.P., Alia-Klein, N., Hajcak, G., Telang, F., Wang, G.J., Volkow, N.D., Goldstein, R.Z., 2009. Enhanced choice for viewing cocaine pictures in cocaine addiction. Biological Psychiatry 66, 169–176. Moeller, S.J., Maloney, T., Parvaz, M.A., Alia-Klein, N., Woicik, P.A., Telang, F., Wang, G.J., Volkows, N.D., Goldstein, R.Z., 2010. Impaired insight in cocaine addiction: laboratory evidence and effects on cocaine-seeking behaviour. Brain 133, 1483–1484. Prigatano, G., Weintein, E.A., 1996. Edwin A. Weinstein’s contributions to neuropsychological rehabilitation. Neuropsychological Rehabilitation 6, 305–326. Rinn, W., Desai, N., Rosenblatt, H., Gastfriend, D.R., 2002. Addiction denial and cognitive dysfunction: a preliminary investigation. The Journal of Neuropsychiatry and Clinical Neuroscience 14, 52–57. Stuss, D.T., Alexander, M.P., 2000. Executive functions and the frontal lobes: a conceptual view. Psychological Research 63, 289–298. Stuss, D.T., Levine, B., 2002. Adult clinical neuropsychology: lessons from studies of the frontal lobes. Annual Review of Psychology 53, 401–433. Tomasi, D., Zhang, L., Cottone, L.A., Maloney, T., Telang, F., Caparelli, E.C., Chang, L., Ernst, T., Samaras, D., Squires, N.K., Volkow, N.D., 2007. Is decreased prefrontal cortical sensitivity to monetary reward associated with impaired motivation and selfcontrol in cocaine addiction? American Journal of Psychiatry 164, 43–51. Verdejo-Garcia, A., Rivas-Pe´rez, C., Vilar-Lo´pez, R., Pe´rez-Garcı´a, M., 2007. Strategic self-regulation, decision-making and emotion processing in poly-substance abusers in their first year of abstinence. Drug and Alcohol Dependence 86, 139–146. Verdejo-Garcı´a, A., Pe´rez-Garcı´a, M., 2008. Substance abusers’ selfawareness of the neurobehavioral consequences of addiction. Psychiatry Research 158, 172–180.
Relevant Websites http://www.candaceplattor.com/articles/Denial_and_Addiction. pdf – Definition and types of denial. http://www.tgorski.com/clin_mod/dmc/dmc.htm – Denial management counseling, T. Gorski. http://www.proyectohombrenavarra.org/07documentacion/libroilorea .pdf – Brain and addiction, J. Tirapu.
I. THE NATURE OF ADDICTION