Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions... more Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions and personality disorders. However, progress in understanding and treating impulsivity is limited by a lack of precision and consistency in its definition and assessment. Rapid-response impulsivity (RRI) represents a tendency toward immediate action that occurs with diminished forethought and is out of context with the present demands of the environment. Experts from the International Society for Research on Impulsivity (InSRI) met to discuss and evaluate RRI measures in terms of reliability, sensitivity, and validity, with the goal of helping researchers and clinicians make informed decisions about the use and interpretation of findings from RRI measures. Their recommendations are described in this article. Commonly used clinical and preclinical RRI tasks are described, and considerations are provided to guide task selection. Tasks measuring two conceptually and neurobiologically disti...
Proceedings of the National Academy of Sciences, 2014
Gambling is a naturalistic example of risky decision-making. During gambling, players typically d... more Gambling is a naturalistic example of risky decision-making. During gambling, players typically display an array of cognitive biases that create a distorted expectancy of winning. This study investigated brain regions underpinning gambling-related cognitive distortions, contrasting patients with focal brain lesions to the ventromedial prefrontal cortex (vmPFC), insula, or amygdala ("target patients") against healthy comparison participants and lesion comparison patients (i.e., with lesions that spare the target regions). A slot machine task was used to deliver near-miss outcomes (i.e., nonwins that fall spatially close to a jackpot), and a roulette game was used to examine the gambler's fallacy (color decisions following outcome runs). Comparison groups displayed a heightened motivation to play following near misses (compared with full misses), and manifested a classic gambler's fallacy effect. Both effects were also observed in patients with vmPFC and amygdala damage, but were absent in patients with insula damage. Our findings indicate that the distorted cognitive processing of near-miss outcomes and event sequences may be ordinarily supported by the recruitment of the insula. Interventions to reduce insula reactivity could show promise in the treatment of disordered gambling.
Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions... more Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions and personality disorders. However, progress in understanding and treating impulsivity is limited by a lack of precision and consistency in its definition and assessment. Rapid-response impulsivity (RRI) represents a tendency toward immediate action that occurs with diminished forethought and is out of context with the present demands of the environment. Experts from the International Society for Research on Impulsivity (InSRI) met to discuss and evaluate RRI measures in terms of reliability, sensitivity, and validity, with the goal of helping researchers and clinicians make informed decisions about the use and interpretation of findings from RRI measures. Their recommendations are described in this article. Commonly used clinical and preclinical RRI tasks are described, and considerations are provided to guide task selection. Tasks measuring two conceptually and neurobiologically disti...
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology, Jan 18, 2015
Bipolar disorder is associated with impaired decision-making. Little is known about how treatment... more Bipolar disorder is associated with impaired decision-making. Little is known about how treatment, especially lithium, influences decision-making abilities in bipolar patients when euthymic. We aimed at testing for an association between lithium medication and decision-making performance in remitted bipolar patients. Decision-making was measured using the Iowa Gambling Task in 3 groups of subjects: 34 and 56 euthymic outpatients with bipolar disorder, treated with lithium (monotherapy and lithium combined with anticonvulsant or antipsychotic) and without lithium (anticonvulsant, antipsychotic and combination treatment), respectively, and 152 matched healthy controls. Performance was compared between the 3 groups. In the 90 euthymic patients, the relationship between different sociodemographic and clinical variables and decision-making was assessed by stepwise multivariate regression analysis. Euthymic patients with lithium (p=0.007) and healthy controls (p=0.001) selected significan...
The reclassification of gambling disorder within the Diagnostic and Statistical Manual of Mental ... more The reclassification of gambling disorder within the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) addictions category marks an important step for addiction science. The similarities between gambling disorder and the substance use disorders have been well documented. As gambling is unlikely to exert actively damaging effects on the brain, the cognitive sequelae of gambling disorder may provide insights into addictive vulnerabilities; this idea is critically evaluated in light of recent structural imaging data. The second part of the review analyzes a fundamental question of how a behavior can become addictive in the absence of exogenous drug stimulation. The relative potency of drug and nondrug rewards is considered, alongside evidence that cognitive distortions in the processing of chance (for example, the illusion of control and the gambler's fallacy) may constitute an important added ingredient in gambling. Further understanding of these mechani...
Individuals with alcohol dependence are known to make disadvantageous decisions, possibly caused ... more Individuals with alcohol dependence are known to make disadvantageous decisions, possibly caused by alterations in either reward or punishment sensitivity, which lead to persistent alcohol use despite its adverse consequences. Previous studies in alcohol dependence have mainly focused on reward anticipation processing and results from these studies are mixed. To clarify the nature of the motivational deficit that underlies disadvantageous choice in alcohol dependence, the current study sought to characterize the neural representation of expected value in individuals with alcohol dependence, separating expectancy-related processing of gains and losses, as a function of outcome magnitude and outcome probability. Functional MRI was used to examine brain responses during the expectation of gains and losses in patients with alcohol dependence (n=19) and healthy controls (n=19). The task manipulated outcome magnitude (€1 and €5) and outcome probability (30% and 70%). Compared to healthy controls, patients with alcohol dependence were more responsive to the expectancy of large wins, in the caudate and putamen. This effect was driven by a higher caudate activity in the contrast comparing €5 vs. €1 trials in patients with alcohol dependence. There were no group differences in the responses to the expectancy for loss. The patient group reported lower expectancies of winning in the trial-by-trial ratings. Patients with alcohol dependence showed caudate hyperactivity when expecting wins. The result contrasts with past work using the monetary incentive delay task, showing caudate hypoactivity; the passive nature of our task contrasts with an active response requirement in the MIDT studies.
European archives of psychiatry and clinical neuroscience, 2004
Investigation of neuropsychological functioning in bipolar disorder provides a potential link fro... more Investigation of neuropsychological functioning in bipolar disorder provides a potential link from the prominent cognitive symptoms of the disorder to the underlying neural mechanisms. Continuous performance measures of sustained attention have yielded consistent findings in bipolar disorder patients. There are impairments that appear to be both state- and trait-related. Impaired target detection may represent one of the most sensitive markers of illness course in bipolardisorder. It is unrelated to residual mood symptomatology and medication status, and is present in patients with good functional recovery. The impairment in target detection is exacerbated in the manic state, and is accompanied by an increased rate of false responding. Sustained attention deficit is present early in the course of the disorder, but becomes more pronounced with repeated episodes. This cognitive profile, of an early-onset, state-modulated, trait marker, is distinct from the profile of attentional disru...
Core aspects of addictive behaviour can be explained in terms of abnormal decision-making. Using ... more Core aspects of addictive behaviour can be explained in terms of abnormal decision-making. Using recording of autonomic function during performance of two gambling tasks, Bechara et al. have recently identified three distinct neuropsychological subtypes in individuals with substance dependence. These subtypes may reflect dissociable patterns of disruption in limbic brain circuitry.
Gambling is pertinent to neuroscience research for at least two reasons. First, gambling is a nat... more Gambling is pertinent to neuroscience research for at least two reasons. First, gambling is a naturalistic and pervasive example of risky decision making, and thus gambling games can provide a paradigm for the investigation of human choice behavior and "irrationality." Second, excessive gambling involvement (i.e., pathological gambling) is currently conceptualized as a behavioral addiction, and research on this condition may provide insights into addictive mechanisms in the absence of exogenous drug effects. This article is a summary of topics covered in a Society for Neuroscience minisymposium, focusing on recent advances in understanding the neural basis of gambling behavior, including translational findings in rodents and nonhuman primates, which have begun to delineate neural circuitry and neurochemistry involved.
Proceedings of the National Academy of Sciences, 2014
Gambling is a naturalistic example of risky decision-making. During gambling, players typically d... more Gambling is a naturalistic example of risky decision-making. During gambling, players typically display an array of cognitive biases that create a distorted expectancy of winning. This study investigated brain regions underpinning gambling-related cognitive distortions, contrasting patients with focal brain lesions to the ventromedial prefrontal cortex (vmPFC), insula, or amygdala ("target patients") against healthy comparison participants and lesion comparison patients (i.e., with lesions that spare the target regions). A slot machine task was used to deliver near-miss outcomes (i.e., nonwins that fall spatially close to a jackpot), and a roulette game was used to examine the gambler's fallacy (color decisions following outcome runs). Comparison groups displayed a heightened motivation to play following near misses (compared with full misses), and manifested a classic gambler's fallacy effect. Both effects were also observed in patients with vmPFC and amygdala damage, but were absent in patients with insula damage. Our findings indicate that the distorted cognitive processing of near-miss outcomes and event sequences may be ordinarily supported by the recruitment of the insula. Interventions to reduce insula reactivity could show promise in the treatment of disordered gambling.
Neuropsychological, psychophysiological and functional imaging research has begun to offer insigh... more Neuropsychological, psychophysiological and functional imaging research has begun to offer insights into the everyday difficulties in decision-making experienced by some patients with frontal lobe damage. It is widely accepted that the ventral prefrontal cortex plays a pivotal role in social and emotional decision-making. This article will review experimental findings using the Iowa Gambling Task and the Cambridge Gamble Task that explore the brain mechanisms of decision-making. Convergent evidence from the two tasks confirms the importance of ventral PFC, but also highlights the relevance of lesion laterality, lesion aetiology, and the contribution of other brain regions (including the dorsal prefrontal cortex and amygdala) to decision-making abilities. The extent to which disrupted decision-making can be separated from the broader domain of executive function is discussed.
Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions... more Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions and personality disorders. However, progress in understanding and treating impulsivity is limited by a lack of precision and consistency in its definition and assessment. Rapid-response impulsivity (RRI) represents a tendency toward immediate action that occurs with diminished forethought and is out of context with the present demands of the environment. Experts from the International Society for Research on Impulsivity (InSRI) met to discuss and evaluate RRI measures in terms of reliability, sensitivity, and validity, with the goal of helping researchers and clinicians make informed decisions about the use and interpretation of findings from RRI measures. Their recommendations are described in this article. Commonly used clinical and preclinical RRI tasks are described, and considerations are provided to guide task selection. Tasks measuring two conceptually and neurobiologically disti...
Proceedings of the National Academy of Sciences, 2014
Gambling is a naturalistic example of risky decision-making. During gambling, players typically d... more Gambling is a naturalistic example of risky decision-making. During gambling, players typically display an array of cognitive biases that create a distorted expectancy of winning. This study investigated brain regions underpinning gambling-related cognitive distortions, contrasting patients with focal brain lesions to the ventromedial prefrontal cortex (vmPFC), insula, or amygdala ("target patients") against healthy comparison participants and lesion comparison patients (i.e., with lesions that spare the target regions). A slot machine task was used to deliver near-miss outcomes (i.e., nonwins that fall spatially close to a jackpot), and a roulette game was used to examine the gambler's fallacy (color decisions following outcome runs). Comparison groups displayed a heightened motivation to play following near misses (compared with full misses), and manifested a classic gambler's fallacy effect. Both effects were also observed in patients with vmPFC and amygdala damage, but were absent in patients with insula damage. Our findings indicate that the distorted cognitive processing of near-miss outcomes and event sequences may be ordinarily supported by the recruitment of the insula. Interventions to reduce insula reactivity could show promise in the treatment of disordered gambling.
Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions... more Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions and personality disorders. However, progress in understanding and treating impulsivity is limited by a lack of precision and consistency in its definition and assessment. Rapid-response impulsivity (RRI) represents a tendency toward immediate action that occurs with diminished forethought and is out of context with the present demands of the environment. Experts from the International Society for Research on Impulsivity (InSRI) met to discuss and evaluate RRI measures in terms of reliability, sensitivity, and validity, with the goal of helping researchers and clinicians make informed decisions about the use and interpretation of findings from RRI measures. Their recommendations are described in this article. Commonly used clinical and preclinical RRI tasks are described, and considerations are provided to guide task selection. Tasks measuring two conceptually and neurobiologically disti...
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology, Jan 18, 2015
Bipolar disorder is associated with impaired decision-making. Little is known about how treatment... more Bipolar disorder is associated with impaired decision-making. Little is known about how treatment, especially lithium, influences decision-making abilities in bipolar patients when euthymic. We aimed at testing for an association between lithium medication and decision-making performance in remitted bipolar patients. Decision-making was measured using the Iowa Gambling Task in 3 groups of subjects: 34 and 56 euthymic outpatients with bipolar disorder, treated with lithium (monotherapy and lithium combined with anticonvulsant or antipsychotic) and without lithium (anticonvulsant, antipsychotic and combination treatment), respectively, and 152 matched healthy controls. Performance was compared between the 3 groups. In the 90 euthymic patients, the relationship between different sociodemographic and clinical variables and decision-making was assessed by stepwise multivariate regression analysis. Euthymic patients with lithium (p=0.007) and healthy controls (p=0.001) selected significan...
The reclassification of gambling disorder within the Diagnostic and Statistical Manual of Mental ... more The reclassification of gambling disorder within the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) addictions category marks an important step for addiction science. The similarities between gambling disorder and the substance use disorders have been well documented. As gambling is unlikely to exert actively damaging effects on the brain, the cognitive sequelae of gambling disorder may provide insights into addictive vulnerabilities; this idea is critically evaluated in light of recent structural imaging data. The second part of the review analyzes a fundamental question of how a behavior can become addictive in the absence of exogenous drug stimulation. The relative potency of drug and nondrug rewards is considered, alongside evidence that cognitive distortions in the processing of chance (for example, the illusion of control and the gambler's fallacy) may constitute an important added ingredient in gambling. Further understanding of these mechani...
Individuals with alcohol dependence are known to make disadvantageous decisions, possibly caused ... more Individuals with alcohol dependence are known to make disadvantageous decisions, possibly caused by alterations in either reward or punishment sensitivity, which lead to persistent alcohol use despite its adverse consequences. Previous studies in alcohol dependence have mainly focused on reward anticipation processing and results from these studies are mixed. To clarify the nature of the motivational deficit that underlies disadvantageous choice in alcohol dependence, the current study sought to characterize the neural representation of expected value in individuals with alcohol dependence, separating expectancy-related processing of gains and losses, as a function of outcome magnitude and outcome probability. Functional MRI was used to examine brain responses during the expectation of gains and losses in patients with alcohol dependence (n=19) and healthy controls (n=19). The task manipulated outcome magnitude (€1 and €5) and outcome probability (30% and 70%). Compared to healthy controls, patients with alcohol dependence were more responsive to the expectancy of large wins, in the caudate and putamen. This effect was driven by a higher caudate activity in the contrast comparing €5 vs. €1 trials in patients with alcohol dependence. There were no group differences in the responses to the expectancy for loss. The patient group reported lower expectancies of winning in the trial-by-trial ratings. Patients with alcohol dependence showed caudate hyperactivity when expecting wins. The result contrasts with past work using the monetary incentive delay task, showing caudate hypoactivity; the passive nature of our task contrasts with an active response requirement in the MIDT studies.
European archives of psychiatry and clinical neuroscience, 2004
Investigation of neuropsychological functioning in bipolar disorder provides a potential link fro... more Investigation of neuropsychological functioning in bipolar disorder provides a potential link from the prominent cognitive symptoms of the disorder to the underlying neural mechanisms. Continuous performance measures of sustained attention have yielded consistent findings in bipolar disorder patients. There are impairments that appear to be both state- and trait-related. Impaired target detection may represent one of the most sensitive markers of illness course in bipolardisorder. It is unrelated to residual mood symptomatology and medication status, and is present in patients with good functional recovery. The impairment in target detection is exacerbated in the manic state, and is accompanied by an increased rate of false responding. Sustained attention deficit is present early in the course of the disorder, but becomes more pronounced with repeated episodes. This cognitive profile, of an early-onset, state-modulated, trait marker, is distinct from the profile of attentional disru...
Core aspects of addictive behaviour can be explained in terms of abnormal decision-making. Using ... more Core aspects of addictive behaviour can be explained in terms of abnormal decision-making. Using recording of autonomic function during performance of two gambling tasks, Bechara et al. have recently identified three distinct neuropsychological subtypes in individuals with substance dependence. These subtypes may reflect dissociable patterns of disruption in limbic brain circuitry.
Gambling is pertinent to neuroscience research for at least two reasons. First, gambling is a nat... more Gambling is pertinent to neuroscience research for at least two reasons. First, gambling is a naturalistic and pervasive example of risky decision making, and thus gambling games can provide a paradigm for the investigation of human choice behavior and "irrationality." Second, excessive gambling involvement (i.e., pathological gambling) is currently conceptualized as a behavioral addiction, and research on this condition may provide insights into addictive mechanisms in the absence of exogenous drug effects. This article is a summary of topics covered in a Society for Neuroscience minisymposium, focusing on recent advances in understanding the neural basis of gambling behavior, including translational findings in rodents and nonhuman primates, which have begun to delineate neural circuitry and neurochemistry involved.
Proceedings of the National Academy of Sciences, 2014
Gambling is a naturalistic example of risky decision-making. During gambling, players typically d... more Gambling is a naturalistic example of risky decision-making. During gambling, players typically display an array of cognitive biases that create a distorted expectancy of winning. This study investigated brain regions underpinning gambling-related cognitive distortions, contrasting patients with focal brain lesions to the ventromedial prefrontal cortex (vmPFC), insula, or amygdala ("target patients") against healthy comparison participants and lesion comparison patients (i.e., with lesions that spare the target regions). A slot machine task was used to deliver near-miss outcomes (i.e., nonwins that fall spatially close to a jackpot), and a roulette game was used to examine the gambler's fallacy (color decisions following outcome runs). Comparison groups displayed a heightened motivation to play following near misses (compared with full misses), and manifested a classic gambler's fallacy effect. Both effects were also observed in patients with vmPFC and amygdala damage, but were absent in patients with insula damage. Our findings indicate that the distorted cognitive processing of near-miss outcomes and event sequences may be ordinarily supported by the recruitment of the insula. Interventions to reduce insula reactivity could show promise in the treatment of disordered gambling.
Neuropsychological, psychophysiological and functional imaging research has begun to offer insigh... more Neuropsychological, psychophysiological and functional imaging research has begun to offer insights into the everyday difficulties in decision-making experienced by some patients with frontal lobe damage. It is widely accepted that the ventral prefrontal cortex plays a pivotal role in social and emotional decision-making. This article will review experimental findings using the Iowa Gambling Task and the Cambridge Gamble Task that explore the brain mechanisms of decision-making. Convergent evidence from the two tasks confirms the importance of ventral PFC, but also highlights the relevance of lesion laterality, lesion aetiology, and the contribution of other brain regions (including the dorsal prefrontal cortex and amygdala) to decision-making abilities. The extent to which disrupted decision-making can be separated from the broader domain of executive function is discussed.
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