Reduced calibration between subjective and objective measures of episodic future thinking in alcohol use disorder.

BACKGROUND: A reduced capacity to mentally simulate future scenarios could be of clinical importance in alcohol use disorder (AUD). However, little is known about the mechanisms underlying episodic future thinking (EFT) impairment in AUD. METHODS: We tested patients with severe AUD using two measures of EFT: the individual's own subjective experience of their imaginings (phenomenology) and the objective number of details included in imagined events, as assessed by an independent observer (examination). The comparison between the two measures allowed us to investigate the extent to which the subjective and objective characteristics of EFT are calibrated in healthy and AUD participants matched for age, education, and gender. The possible impact of cognitive functioning and disturbed mood on EFT measures was also investigated. RESULTS: In terms of objective details of EFT, patients with AUD (n = 40) generated fewer episodic components and more non-episodic components than control participants (n = 40), even when controlling for cognitive functioning. However, self-ratings of phenomenological characteristics indicated that participants with AUD perceived imagined future events at a similar level of detail as control participants. Additionally, there was a significant correlation between objective and subjective measures in healthy individuals but not in the AUD group. A higher depression score in the AUD group was not associated with the EFT measures. CONCLUSIONS: These results suggest a distorted self-assessment of the richness of imagined future events in individuals with AUD. We discuss these apparent limitations in metacognitive abilities and verbal descriptions of imagined events among individuals with AUD and their clinical implications.

On the Processes Underlying the Relationship Between Alexithymia and Gambling Severity.

A great number of individuals with persistent problematic gambling behavior exhibit alexithymic tendencies, greater impulsivity, impaired working memory and poor mood. However, the relationship between these cognitive, affective and personality factors in problem gambling remains poorly understood. Our aim was to investigate multiple pathways of the alexithymia and problem gambling relationship. One hundred and six male subjects with different levels of gambling problem severity were recruited. Alexithymia, impulsivity and verbal working memory were evaluated, and their relationships to disordered gambling was examined by means of a path analysis. Results indicate that alexithymia is related to an increase in the severity of gambling indirectly, i.e., through distress severity. In addition, a rise of alexithymic tendencies was also associated with problem gambling severity through enhanced impulsivity that directly increased distress. Working memory capacity failed to significantly impact our path model. Overall, our findings contribute a new finding to the literature by highlighting the importance of alexithymia, in addition to impulsivity, in the understanding of gambling problem severity and its clinical course.

Future-oriented mental time travel in individuals with disordered gambling.

This study investigated the ability of individuals with disordered gambling to imagine future events. Problem gamblers (n=35) and control participants (n=35) were asked to imagine positive and negative future events for three temporal distances (one week, one year, 5-10years). Then, a variety of phenomenological aspects of their future thoughts (e.g., sensory and contextual details, autonoetic consciousness) were rated. Compared to control subjects, problem gamblers generated fewer positive and negative events across all temporal distances, an impairment that was correlated to verbal fluency scores. Furthermore, problem gamblers rated imagined events as containing fewer sensory and contextual details, and lacking autonoetic consciousness. These findings demonstrate that problem gambling is associated with a reduced future-oriented mental time travel ability and, in particular, with diminished autonoetic consciousness when imagining future events.

A Comparative Event-Related Potentials Study between Alcohol Use Disorder, Gambling Disorder and Healthy Control Subjects through a Contextual Go/NoGo Task.

(1) Background: Inhibitory and rewarding processes that mediate attentional biases to addiction-related cues may slightly differ between patients suffering from alcohol use (AUD) or gambling (GD) disorder. (2) Methods: 23 AUD inpatients, 19 GD patients, and 22 healthy controls performed four separate Go/NoGo tasks, in, respectively, an alcohol, gambling, food, and neutral long-lasting cueing context during the recording of event-related potentials (ERPs). (3) Results: AUD patients showed a poorer inhibitory performance than controls (slower response latencies, lower N2d, and delayed P3d components). In addition, AUD patients showed a preserved inhibitory performance in the alcohol-related context (but a more disrupted one in the food-related context), while GD patients showed a specific inhibitory deficit in the game-related context, both indexed by N2d amplitude modulations. (4) Conclusions: Despite sharing common addiction-related mechanisms, AUD and GD patients showed different patterns of response to (non-)rewarding cues that should be taken into account in the therapeutic context.

The modulation of acute stress on model-free and model-based reinforcement learning in gambling disorder.

Background and aims: Experiencing acute stress is common in behavioral addictions such as gambling disorder. Additionally, like most substance-induced addictions, aberrant decision-making wherein a reactive habit-induced response (conceptualized as a Model-free [MF] in reinforcement learning) suppresses a flexible goal-directed response (conceptualized as a Model-based [MB]) is also common in gambling disorder. In the current study we investigated the influence of acute stress on the balance between habitual response and the goal-directed system. Methods: A sample of N = 116 problem gamblers (PG) and healthy controls (HC) performed an acute stress task - the Socially Evaluated Cold pressure task (SECPT) - or a control task. Self-reported stress and salivary cortisol were collected as measures of acute stress. Following the SECPT, participants performed the Two-Step Markov Task to account for the relative contribution of MB and MF strategies. Additionally, verbal working memory and IQ measures were collected to account for their mediating effects on the orchestration between MB/MF and the impact of stress. Results: Both groups had comparable baseline and stress-induced cortisol response to the SECPT. Non-stressed PG displayed lower MB learning than HC. MANOVA and regression analyses showed a deleterious effect of stress-induced cortisol response on the orchestration between MB and MF learning in HC but not in PG. These effects remained when controlling for working memory and IQ. Discussion and Conclusions: We found an abnormal pattern of modulation of stress on the orchestration between MB and MF learning among PG. Several interpretations and future research directions are discussed.

Habitual Routines and Automatic Tendencies Differential Roles in Alcohol Misuse Among Undergraduates.

There is a debate over whether actions that resist devaluation (i.e., compulsive alcohol consumption) are primarily habit- or goal-directed. The incentive habit account of compulsive actions has received support from behavioral paradigms and brain imaging. In addition, the self-reported Creature of Habit Scale (COHS) has been proposed to capture inter-individual differences in habitual tendencies. It is subdivided into two dimensions: routine and automaticity. We first considered a French version of this questionnaire for validation, based on a sample of 386 undergraduates. The relationship between two dimensions of habit and the risk of substance use disorder and impulsive personality traits was also investigated. COHS has good psychometric properties with both features of habits positively associated with an Obsessive-Compulsive Inventory score. Besides, the propensity to rely more on routines was associated with lower levels of alcohol abuse and nicotine use, suggesting that some degree of routine might act as a protective factor against substance use. In contrast, a high automaticity score was associated with an increased risk of harmful alcohol use. These results demonstrate that the COHS is a valid measure of habitual tendencies and represents a useful tool for capturing inter-individual variations in drug use problems in undergraduates.

Reduced model-based decision-making in gambling disorder.

Compulsive behaviors (e.g., addiction) can be viewed as an aberrant decision process where inflexible reactions automatically evoked by stimuli (habit) take control over decision making to the detriment of a more flexible (goal-oriented) behavioral learning system. These behaviors are thought to arise from learning algorithms known as "model-based" and "model-free" reinforcement learning. Gambling disorder, a form of addiction without the confound of neurotoxic effects of drugs, showed impaired goal-directed control but the way in which problem gamblers (PG) orchestrate model-based and model-free strategies has not been evaluated. Forty-nine PG and 33 healthy participants (CP) completed a two-step sequential choice task for which model-based and model-free learning have distinct and identifiable trial-by-trial learning signatures. The influence of common psychopathological comorbidities on those two forms of learning were investigated. PG showed impaired model-based learning, particularly after unrewarded outcomes. In addition, PG exhibited faster reaction times than CP following unrewarded decisions. Troubled mood, higher impulsivity (i.e., positive and negative urgency) and current and chronic stress reported via questionnaires did not account for those results. These findings demonstrate specific reinforcement learning and decision-making deficits in behavioral addiction that advances our understanding and may be important dimensions for designing effective interventions.

Impaired non-verbal emotion processing in Pathological Gamblers.

Impaired perception of emotion in others has been described and confirmed in addictions with substances, but no such data exists regarding addictions without substances. As it has been hypothesized that toxic effect of substances on the brain was responsible for the impairments described, studying addictions without substances could be of interest to confirm this hypothesis. Twenty-two male pathological gamblers were compared to 22 male healthy controls matched for age and education level on non-verbal emotion perception tasks including faces, voices, and musical excerpts. Depression and anxiety levels were controlled for. Pathological gamblers significantly underestimated the intensity of peacefulness in music, and overall they were less accurate when reading emotion in voices and faces. They also overestimated emotional intensity in neutral voices and faces. Although anxiety levels did account for accuracy problems when detecting fear in voices and for overestimating emotions in neutral faces, anxiety levels did not explain the range of deficits observed. This is the first study showing non-verbal perception deficits in a purely behavioural addiction. These findings show that deficits in decoding non-verbal signals are associated with addictive behaviours per se, and are not due solely to toxic effects of substances on the brain.

Increased cortical activity in binge drinkers during working memory task: a preliminary assessment through a functional magnetic resonance imaging study.

BACKGROUND: Cerebral dysfunction is a common feature of both chronic alcohol abusers and binge drinkers. Here, we aimed to study whether, at equated behavioral performance levels, binge drinkers exhibited increased neural activity while performing simple cognitive tasks. METHODS: Thirty-two participants (16 binge drinkers and 16 matched controls) were scanned using functional magnetic resonance imaging (fMRI) while performing an n-back working memory task. In the control zero-back (N0) condition, subjects were required to press a button with the right hand when the number "2" was displayed. In the two-back (N2) condition, subjects had to press a button when the displayed number was identical to the number shown two trials before. RESULTS: fMRI analyses revealed higher bilateral activity in the pre-supplementary motor area in binge drinkers than matched controls, even though behavioral performances were similar. Moreover, binge drinkers showed specific positive correlations between the number of alcohol doses consumed per occasion and higher activity in the dorsomedial prefrontal cortex, as well as between the number of drinking occasions per week and higher activity in cerebellum, thalamus and insula while performing the N2 memory task. CONCLUSIONS: Binge alcohol consumption leads to possible compensatory cerebral changes in binge drinkers that facilitate normal behavioral performance. These changes in cerebral responses may be considered as vulnerability factors for developing adult substance use disorders.