The neurocircuitry of impaired insight in drug addiction

Soul, body and mental health - applying Rabbi Moshe de Maimon's philosophy to the contemporary phenomenon of drug addiction

In modern psychiatry, drug addiction is considered as mainly a mental disorder and a brain disease problem, of complex aetiology. In addition, drug addiction has been characterized as a loss of willpower or akrasia, and even a sin. In this essay, I analyse Maimonides' (Rambam's) treatises More Ha-Nevuchim (Guide for the Perplexed) and Shemona Perakim (The Eight Chapters). He asserts that the soul is one, but has many different faculties (functions) and is intrinsically linked to the body. I argue that drug addiction is a psychological, social-moral deviance, as well as straying from God's path. Addiction is a disorder of the soul and body. Consequently, healing should include social-moral guidelines as well as physical/bodily health.

Neuromarkers in addiction: definitions, development strategies, and recent advances

Substance use disorders (SUDs) are the most costly and prevalent psychiatric conditions. Recent calls emphasize a need for biomarkers-measurable, stable indicators of normal and abnormal processes and response to treatment or environmental agents-and, in particular, brain-based neuromarkers that will advance understanding of the neurobiological basis of SUDs and clinical practice. To develop neuromarkers, researchers must be grounded in evidence that a putative marker (i) is sensitive and specific to the psychological phenomenon of interest, (ii) constitutes a predictive model, and (iii) generalizes to novel observations (e.g., through internal cross-validation and external application to novel data). These neuromarkers may be used to index risk of developing SUDs (susceptibility), classify individuals with SUDs (diagnostic), assess risk for progression to more severe pathology (prognostic) or index current severity of pathology (monitoring), detect response to treatment (response), and predict individualized treatment outcomes (predictive). Here, we outline guidelines for developing and assessing neuromarkers, we then review recent advances toward neuromarkers in addiction neuroscience centering our discussion around neuromarkers of craving-a core feature of SUDs. In doing so, we specifically focus on the Neurobiological Craving Signature (NCS), which show great promise for meeting the demand of neuromarkers.

The selective D3Receptor antagonist VK4-116 reverses loss of insight caused by self-administration of cocaine in rats

Chronic psychostimulant use causes long-lasting changes to neural and cognitive function that persist after long periods of abstinence. As cocaine users transition from drug use to abstinence, a parallel transition from hyperactivity to hypoactivity has been found in orbitofrontal-striatal glucose metabolism and striatal D2/D3-receptor activity. Targeting these changes pharmacologically, using highly selective dopamine D3-receptor (D3R) antagonists and partial agonists, has shown promise in reducing drug-taking, and attenuating relapse in animal models of cocaine and opioid use disorder. However, much less attention has been paid to treating the loss of insight, operationalized as the inability to infer likely outcomes, associated with chronic psychostimulant use. Here we tested the selective D3R antagonist VK4-116 as a treatment for this loss in rats with a prior history of cocaine use. Male and female rats were first trained to self-administer cocaine or a sucrose liquid for 2 weeks. After 4 weeks of abstinence, performance was assessed using a sensory preconditioning (SPC) learning paradigm. Rats were given VK4-116 (15 mg/kg, i.p.) or vehicle 30 min prior to each SPC training session, thus creating four drug-treatment groups: sucrose-vehicle, sucrose-VK4-116, cocaine-vehicle, cocaine-VK4-116. The control groups (sucrose-vehicle, sucrose-VK4-116) showed normal sensory preconditioning, whereas cocaine use (cocaine-vehicle) selectively disrupted responding to the preconditioned cue, an effect that was reversed in the cocaine-VK4-116 group, which demonstrating responding to the preconditioned cue at levels comparable to controls. These preclinical findings demonstrate that highly selective dopamine D3R antagonists, particularly VK4-116, can reverse the long-term negative behavioral consequences of cocaine use.

Tobacco Images Choice and Its Association with Craving and Dependence in Cigarette Smokers

Introduction

Increased salience of drug-related cues over non-drug reinforcers can drive drug use and contribute to tobacco use disorder (TUD). An important scientific and clinical goal is to effectively measure this elevated drug-seeking behavior in TUD. However, most TUD assessments rely on self-reported cravings and cigarette consumption, not providing an objective measure of the impact of drug-cues on biasing behavior towards drugs. The probabilistic image choice (PIC) task investigates the choice of viewing drug-related pictures as compared to other salient pictures (e.g., pleasant and unpleasant). This study aimed to develop and validate the PIC task for TUD and evaluate the associations between behavioral choice and tobacco craving, daily cigarette consumption, quit attempts and motivation to quit, and nicotine dependence (the Fagerström score).

Methods

We recruited 468 smokers and 121 nonsmokers using the Prolific online platform. Participants performed the PIC task twice (at a one-month interval) and completed other measures relevant to TUD.

Results

compared to nonsmokers, tobacco smokers selected to view significantly more tobacco images and less pleasant (non-drug reinforcer) images, a profile that remained stable at retest. Individual differences in choice of tobacco as compared to pleasant images on the PIC task were associated with craving but not with the other tobacco dependence measures, suggesting that the task may serve as a behavioral proxy measure of drug "wanting" rather than of cumulative nicotine exposure or physical dependence.

Conclusions

these results suggest that the PIC task can be a valuable tool for objectively assessing craving-associated tobacco seeking in TUD.

Neural correlates of drinking reduction during a clinical trial of cognitive behavioral therapy for alcohol use disorder

BACKGROUND

Cognitive behavioral therapy (CBT) is an effective treatment for alcohol use disorder (AUD). We hypothesized that the dorsolateral prefrontal cortex (DLPFC), a region implicated in cognitive control and goal-directed behavior, plays a role in behavior change during CBT by facilitating the regulation of craving (ROC).

METHODS

Treatment-seeking participants with AUD (N = 22) underwent functional magnetic resonance imaging (fMRI) scanning both before and after a 12-week, single-arm trial of CBT, using an ROC task that was previously shown to engage the DLPFC.

RESULTS

We found that both the percentage of heavy drinking days (PHDD) and the overall self-reported alcohol craving measured during the ROC task were significantly reduced from pre- to post-CBT. However, we did not find significant changes over time in either the ability to regulate craving or regulation-related activity in any brain region. We found a significant 3-way interaction between the effects of cue-induced craving, cue-induced brain activity and timepoint of assessment (pre- or post-CBT) on PHDD in the left DLPFC. Follow-up analysis showed that cue-induced craving was associated with cue-induced activity in the left DLPFC among participants who ceased heavy drinking during CBT, both at pre-CBT and post-CBT timepoints. No such associations were present at either timepoint among participants who continued to drink heavily.

CONCLUSIONS

These results suggest that patients in whom DLPFC functioning is more strongly related to cue-induced craving may preferentially respond to CBT.

Association of Cortico-Striatal Engagement During Cue Reactivity, Reappraisal, and Savoring of Drug and Non-Drug Stimuli With Craving in Heroin Addiction

OBJECTIVE

The authors investigated cortico-striatal reactivity to drug cues (as compared with neutral and food cues), drug cue reappraisal, food cue savoring, and their correlations with heroin craving in individuals with heroin use disorder compared with healthy control subjects.

METHODS

Cross-sectional changes in functional MRI blood-oxygen-level-dependent signal during a novel cue reactivity task were assessed in 32 individuals with heroin use disorder (mean age, 40.3 years; seven women) and 21 age- and sex-matched healthy control subjects (mean age, 40.6 years; eight women).

RESULTS

Drug cue reactivity (vs. neutral cues) was significantly higher in the nucleus accumbens in the heroin use disorder group compared with the control group and nominally significantly higher in the orbitofrontal cortex (OFC); ventromedial prefrontal cortex (vmPFC) activity positively correlated with drug craving. Drug cue reactivity (vs. salient food cues) was also higher in the inferior frontal gyrus (IFG) in the heroin use disorder group compared with the control group. Drug reappraisal and food savoring (vs. passive viewing) showed increased IFG and supplementary motor area activity in all participants; in the heroin use disorder group, higher IFG/dorsolateral PFC (dlPFC) activity during drug reappraisal and rostral anterior cingulate cortex (ACC) activity during food savoring were associated with lower drug cue-induced craving and longer treatment, respectively. A direct comparison of regulation of reactivity to both salient cues revealed widespread group differences such that drug reappraisal activity was higher in the heroin use disorder group and food savoring activity was higher in the control group in both cortical (e.g., OFC, IFG, ACC, vmPFC, and insula) and subcortical (e.g., dorsal striatum and hippocampus) regions. Higher drug reappraisal versus food savoring in the dlPFC was associated with higher self-reported methadone dosage in the heroin use disorder group.

CONCLUSIONS

The results demonstrate cortico-striatal upregulation during drug cue exposure and impaired reactivity during processing of alternative non-drug rewards in the heroin use disorder group. Normalizing cortico-striatal function by reducing drug cue reactivity and enhancing natural reward valuation may inform therapeutic mechanisms for reducing drug craving and seeking in heroin addiction.

Craving dynamics and related cerebral substrates predict timing of use in alcohol, tobacco, and cannabis use disorders

Background

Patients treated for Substance Use Disorders exhibit highly fluctuating patterns of craving that could reveal novel prognostic markers of use. Accordingly, we 1) measured fluctuations within intensively repeated measures of craving and 2) linked fluctuations of craving to connectivity indices within resting-state (rs) brain regions to assess their relation to use among patients undergoing treatment for Alcohol, Tobacco and Cannabis Use Disorders.

Method

Participants -64 individuals with SUD for tobacco, alcohol, or cannabis and 35 healthy controls-completed a week of Ecological Momentary Assessment (EMA) during which they reported craving intensity and substance use five times daily. Before EMA, a subsample of 50 patients, and 34 healthy controls also completed resting-state (rs)-MRI acquisitions. Craving temporal dynamics within each day were characterized using Standard Deviation (SD), Auto-Correlation Factor (ACF), and Mean Successive Square Difference (MSSD). Absolute Difference (AD) in craving between assessments was a prospective prediction measure.

Results

Within-day, higher MSSD predicted greater substance use while controlling for mean craving. Prospectively higher AD predicted later increased substance use independently of previous use or craving level. Moreover, MSSD was linked to strength in five functional neural connections, most involving frontotemporal systems. Cerebello-thalamic and thalamo-frontal connectivity were also linked to substance use and distinguished the SUD from the controls.

Conclusion

To the best of our knowledge, this is the first study to indicate that instability in craving may be a trigger for use in several SUD types, beyond the known effect of craving intensity.

Insular volumetry in severe alcohol use disorder and Korsakoff's syndrome through an anatomical parcellation: Let us go back to basics

Functional neuroimaging has demonstrated the key role played by the insula in severe alcohol use disorder (sAUD), notably through its involvement in craving and body signals processing. However, the anatomical counterpart of these functional modifications in sAUD patients with and without neurological complications remains largely unexplored, especially using state-of-the-art parcellation tools. We thus compared the grey matter volume of insular subregions (form anterior to posterior: anterior inferior cortex, anterior short gyrus, middle short gyrus, posterior short gyrus, anterior long gyrus, posterior long gyrus) in 50 recently detoxified patients with sAUD, 19 patients with Korsakoff's syndrome (KS) and 36 healthy controls (HC). We used a mixed linear model analysis to explore group differences in the six subregions grey matter volume and lateralization differences. Insular macrostructure was globally affected to the same extent in sAUD with and without KS, indicating that these brain abnormalities may be related to alcohol consumption per se, rather than to the presence of alcohol-related neurological complications. Insular atrophy showed a right-sided lateralization effect and was especially marked in the posterior insula, a region associated with visceral information processing and the embodiment effect of a substance, from which craving arises. Anatomical damages might thus underlie the previously reported altered insular activations and their behavioural counterparts.

The selective D3-Receptor antagonist VK4-116 effectively treats behavioral inflexibility in rats caused by self-administration and withdrawal from cocaine

Chronic psychostimulant use can cause long lasting changes to neural and cognitive function that persist even after long periods of abstinence. As cocaine users transition from drug use to abstinence, a parallel transition from hyperactivity to hypoactivity has been found in orbitofrontal-striatal glucose metabolism, and striatal D2/D3 receptor activity. Targeting these changes pharmacologically, using highly selective dopamine D3 receptor (D3R) antagonists and partial agonists, has shown significant promise in reducing drug-taking, and attenuating relapse in animal models of cocaine and opioid use disorder. However, much less attention has been focused on treating inflexible and potentially maladaptive non-drug behaviors following chronic psychostimulant use. Here we tested the selective D3R antagonist VK4-116 as a treatment for the long-term behavioral inflexibility in abstinent male and female rats with a prior history of chronic cocaine use. Rats were first trained to self-administer cocaine (0.75 mg/kg/reinforcer) or a sucrose liquid (10%, .04 mL/reinforcer) for 2 weeks (FR1 schedule, max 60 reinforcers in 3 hrs/ day), followed by 4 weeks of abstinence. Cognitive and behavioral flexibilities were then assessed using a sensory preconditioning (SPC) learning paradigm. Rats were given an VK4-116 (15 mg/kg, i.p.) or vehicle 30 mins prior to each SPC training session, thus creating four drug-treatment groups: sucrose-vehicle, sucrose-VK4-116, cocaine-vehicle, cocaine-VK4-116. The control groups (sucrose-vehicle, sucrose-VK4-116) demonstrated significant evidence of flexible SPC behavior, whereas cocaine use (cocaine-vehicle) disrupted SPC behavior. Remarkably, the D3R antagonist VK4-116 mitigated this cocaine deficit in the cocaine-VK4-116 group, demonstrating flexible SPC to levels comparable to the control groups. These preclinical findings demonstrate that highly selective dopamine D3R antagonists, particularly VK4-116, show significant promise as a pharmacological treatment for the long-term negative behavioral consequences of cocaine use disorder.

Accumbal-thalamic connectivity and associated glutamate alterations in human cocaine craving: A state-dependent rs-fMRI and 1H-MRS study

Craving is a core symptom of cocaine use disorder and a major factor for relapse risk. To date, there is no pharmacological therapy to treat this disease or at least to alleviate cocaine craving as a core symptom. In animal models, impaired prefrontal-striatal signalling leading to altered glutamate release in the nucleus accumbens appear to be the prerequisite for cocaine-seeking. Thus, those network and metabolic changes may constitute the underlying mechanisms for cocaine craving and provide a potential treatment target. In humans, there is recent evidence for corresponding glutamatergic alterations in the nucleus accumbens, however, the underlying network disturbances that lead to this glutamate imbalance remain unknown. In this state-dependent randomized, placebo-controlled, double-blinded, cross-over multimodal study, resting state functional magnetic resonance imaging in combination with small-voxel proton magnetic resonance spectroscopy (voxel size: 9.4 × 18.8 × 8.4 mm3) was applied to assess network-level and associated neurometabolic changes during a non-craving and a craving state, induced by a custom-made cocaine-cue film, in 18 individuals with cocaine use disorder and 23 healthy individuals. Additionally, we assessed the potential impact of a short-term challenge of N-acetylcysteine, known to normalize disturbed glutamate homeostasis and to thereby reduce cocaine-seeking in animal models of addiction, compared to a placebo. We found increased functional connectivity between the nucleus accumbens and the dorsolateral prefrontal cortex during the cue-induced craving state. However, those changes were not linked to alterations in accumbal glutamate levels. Whereas we additionally found increased functional connectivity between the nucleus accumbens and a midline part of the thalamus during the cue-induced craving state. Furthermore, obsessive thinking about cocaine and the actual intensity of cocaine use were predictive of cue-induced functional connectivity changes between the nucleus accumbens and the thalamus. Finally, the increase in accumbal-thalamic connectivity was also coupled with craving-related glutamate rise in the nucleus accumbens. Yet, N-acetylcysteine had no impact on craving-related changes in functional connectivity. Together, these results suggest that connectivity changes within the fronto-accumbal-thalamic loop, in conjunction with impaired glutamatergic transmission, underlie cocaine craving and related clinical symptoms, pinpointing the thalamus as a crucial hub for cocaine craving in humans.

Definition and measurement of alcohol-associated insight in early liver transplantation for acute alcohol-associated hepatitis: A systematic review

BACKGROUND

Alcohol accounts for a large disease burden in hepatology and liver transplantation (LT) and across the globe. Clinical evaluations and decisions about LT candidacy are challenging because they rely on detailed psychosocial assessments and interpretations of psychiatric and substance use disorder data, which often must occur rapidly according to the acuity of end-stage liver disease. Such difficulties commonly occur during the process of candidate selection and liver allocation, particularly during early LT (eLT) in patients with acute alcohol-associated hepatitis (AAH). Patients with AAH commonly have very recent or active substance use, high short-term mortality, psychiatric comorbidities, and compressed evaluation and treatment timetables. LT clinicians report that patients' alcohol-associated insight (AAI) is among the most relevant psychosocial data in this population, yet no studies exist examining how LT teams define and use AAI in eLT or its effect on clinical outcomes. In April 2022, we searched Ovid MEDLINE, Elsevier Embase, EBSCOhost PsycInfo and CINAHL, and Wiley Cochrane Central Register of Controlled Trials for reports describing AAH populations who underwent eLT, which also described psychosocial evaluation parameters. The searches retrieved 1603 unique reports. After eligibility screening, 8 were included in the qualitative analysis. This systematic review reveals that AAI is a poorly defined construct that is not measured in a standardized way. Yet it is a commonly cited parameter in articles that describe the psychosocial evaluation and decision-making of patients undergoing eLT for AAH. This article also discusses the general challenges of assessing AAI during eLT for AAH, existing AAI definitions and rating scales, how AAI has been used to date in the broader hepatology and LT literature, and future areas for clinical and research progress.

Candidate biomarkers in psychiatric disorders: state of the field

The field of psychiatry is hampered by a lack of robust, reliable and valid biomarkers that can aid in objectively diagnosing patients and providing individualized treatment recommendations. Here we review and critically evaluate the evidence for the most promising biomarkers in the psychiatric neuroscience literature for autism spectrum disorder, schizophrenia, anxiety disorders and post-traumatic stress disorder, major depression and bipolar disorder, and substance use disorders. Candidate biomarkers reviewed include various neuroimaging, genetic, molecular and peripheral assays, for the purposes of determining susceptibility or presence of illness, and predicting treatment response or safety. This review highlights a critical gap in the biomarker validation process. An enormous societal investment over the past 50 years has identified numerous candidate biomarkers. However, to date, the overwhelming majority of these measures have not been proven sufficiently reliable, valid and useful to be adopted clinically. It is time to consider whether strategic investments might break this impasse, focusing on a limited number of promising candidates to advance through a process of definitive testing for a specific indication. Some promising candidates for definitive testing include the N170 signal, an event-related brain potential measured using electroencephalography, for subgroup identification within autism spectrum disorder; striatal resting-state functional magnetic resonance imaging (fMRI) measures, such as the striatal connectivity index (SCI) and the functional striatal abnormalities (FSA) index, for prediction of treatment response in schizophrenia; error-related negativity (ERN), an electrophysiological index, for prediction of first onset of generalized anxiety disorder, and resting-state and structural brain connectomic measures for prediction of treatment response in social anxiety disorder. Alternate forms of classification may be useful for conceptualizing and testing potential biomarkers. Collaborative efforts allowing the inclusion of biosystems beyond genetics and neuroimaging are needed, and online remote acquisition of selected measures in a naturalistic setting using mobile health tools may significantly advance the field. Setting specific benchmarks for well-defined target application, along with development of appropriate funding and partnership mechanisms, would also be crucial. Finally, it should never be forgotten that, for a biomarker to be actionable, it will need to be clinically predictive at the individual level and viable in clinical settings.

Longing to act: Bayesian inference as a framework for craving in behavioral addiction

Traditionally, craving is considered a defining feature of drug addiction. Accumulating evidence suggests that craving can also exist in behavioral addictions (e.g., gambling disorder) without drug-induced effects. However, the degree to which mechanisms of craving overlap between classic substance use disorders and behavioral addictions remains unclear. There is, therefore, an urgent need to develop an overarching theory of craving that conceptually integrates findings across behavioral and drug addictions. In this review, we will first synthesize existing theories and empirical findings related to craving in both drug-dependent and -independent addictive disorders. Building on the Bayesian brain hypothesis and previous work on interoceptive inference, we will then propose a computational theory for craving in behavioral addiction, where the target of craving is execution of an action (e.g., gambling) rather than a drug. Specifically, we conceptualize craving in behavioral addiction as a subjective belief about physiological states of the body associated with action completion and is updated based on both a prior belief ("I need to act to feel good") and sensory evidence ("I cannot act"). We conclude by briefly discussing the therapeutic implications of this framework. In summary, this unified Bayesian computational framework for craving generalizes across addictive disorders, provides explanatory power for ostensibly conflicting empirical findings, and generates strong hypotheses for future empirical studies. The disambiguation of the computational components underlying domain-general craving using this framework will lead to a deeper understanding of, and effective treatment targets for, behavioral and drug addictions.

Effect of environmental enrichment on relapse rates in patients with severe alcohol use disorder: protocol for a randomised controlled trial

INTRODUCTION

Alcohol use disorder (AUD) ranks among the most prevalent psychiatric disorders worldwide. Despite current treatments, more than half of patients relapse within weeks after treatment. In animal models, exposure to environmental enrichment (EE) has been shown to be a promising approach to reduce relapse. However, controlled, multimodal EE is difficult to transpose to humans. To address this gap, this study aims at assessing the effectiveness of exposure to a newly designed EE protocol during AUD treatment in reducing relapse to alcohol use. Our EE will allow an enhancement of the standard intervention, and will combine several promising enrichment factors identified in the literature-physical activity, cognitive stimulation, mindfulness and virtual reality (VR).

METHODS AND ANALYSIS

A randomised controlled trial involving 135 participants receiving treatment for severe AUD will be conducted. Patients will be randomised to an intervention enhancement group or a control group. The enhanced intervention will consist of six 40-min sessions of EE spread over 9 days. During the first 20 min of these sessions, patients will practise mindfulness in multisensory VR, in virtual environments designed to practise mindfulness and use it to regulate craving induced by virtual cues or stress. Then, participants will practise indoor cycling combined with cognitive training exercises. The control group will undergo standard management for AUD. The primary outcome is relapse assessed at 2 weeks after treatment, using a questionnaire and biological indicators. Relapse will be defined as drinking at least five drinks per occasion or drinking at least five times a week. It is predicted that the group receiving the EE intervention will have a lower relapse rate than the control group. The secondary outcomes are relapse at 1 month and 3 months after treatment, craving and drug-seeking behaviour, mindfulness skills acquisition and the effect of the intervention enhancement on the perceived richness of the daily environment, assessed by questionnaires and neuropsychological tasks.

ETHICS AND DISSEMINATION

All participants have to give written informed consent to the investigator. This study is approved by the Ethics Committee Nord Ouest IV of Lille (reference number 2022-A01156-37). Results will be disseminated through presentations, peer-reviewed journals and seminar conferences. All information on ethical considerations and open science practices can be accessed at https://osf.io/b57uj/ TRIAL REGISTRATION NUMBER: NCT05577741.

Serum brain-derived neurotrophic factor levels in patients with schizophrenia and methamphetamine addiction: correlation with Mini-Mental State Examination (MMSE)

Methamphetamine use can induce psychosis resembling acute schizophrenia spectrum psychosis, making it challenging to differentiate between the two based on symptoms alone. Brain-derived neurotrophic factor (BDNF) exerts a critical role in hippocampal neural plasticity, influencing critical cognitive functions such as memory and learning. This study aimed to determine the role of serum BDNF levels in schizophrenia and methamphetamine addiction. A case-control study was conducted involving 50 patients with schizophrenia, 50 patients with methamphetamine addiction, and 50 healthy control subjects recruited from Ibn-Rushed Psychiatric Teaching Hospital in Baghdad. Cognitive impairment was assessed using the Mini-Mental State Examination (MMSE), while serum BDNF levels were measured using ELISA following standardized protocols. The findings revealed significantly lower median levels of BDNF (0.36 pg/ml) in patients with schizophrenia compared to both the control group (0.51 pg/ml) and the methamphetamine group (0.72 pg/ml). Moreover, there was a significant difference observed between the methamphetamine group and the control group. At a cut-off value of BDNF=0.37 pg/ml, the sensitivity and specificity of BDNF in differentiating between schizophrenia and methamphetamine addiction were 84% and 70%, respectively. Serum level of BDNF could be used to differentiate between schizophrenia and methamphetamine addiction when clinical distinctions are challenging to detect.

Interoception Within the Context of Impulsivity and Addiction

Purpose of Review

The goal of this review is to examine the relationship between impulsivity and interoception in addiction, to summarize the current understanding of the topic, identify any gaps in knowledge, and provide directions for future research.

Research Findings

Interoception may be a contributing factor to impulsive behaviour and, thus, addiction. Substance abuse can negatively impact the brain's ability to process interoceptive information and impact the reward system, leading to decreased sensitivity to natural rewards and increased sensitivity to drugs. There is potential for new therapies, such as mindfulness, interoceptive training, brain stimulation, or vagal nerve stimulation to target both impulsivity and interoception in the treatment of addiction.

Summary

Despite a growing interest in interoception in addiction research, further research is needed to better understand the role of interoception in addiction and to develop new methods for studying how individuals with addiction process and perceive internal bodily sensations.

Addiction as a brain disease? A meta-regression comparison of error-related brain potentials between addiction and neurological diseases

The notion that addiction is a "brain disorder" is widespread. However, there is a lack of evidence on the degree of disorder in terms of error processing in addiction. The present meta-analysis aimed at shedding light on this by comparing error-processes with populations with well-recognized brain disorders. We included 17 addiction and 32 neurological disorder studies that compared error-related negativity (ERN) or error positivity (Pe) amplitudes/latencies between experimental and healthy-control groups. Meta-regression analyses were performed for the intergroup comparison and other moderators. Both diagnoses were accompanied by a diminished ERN amplitude, although the degree of impairment was marginally larger in neurological disorders. Neurological disorders presented shorter ERN latencies than addiction when compared with controls. The two groups did not differ in Pe amplitude/latency. Except for a reduced ERN amplitude found along with aging, no other moderator contributed significantly to divergent findings about these four ERP indexes. The results support the brain disease model of addiction, while stressing the importance of quantifying the degrees of brain dysfunctions as a next step.

Addiction and autonomy: Why emotional dysregulation in addiction impairs autonomy and why it matters

An important philosophical issue in the study of addiction is what difference the fact that a person is addicted makes to attributions of autonomy (and responsibility) to their drug-oriented behavior. In spite of accumulating evidence suggesting the role of emotional dysregulation in understanding addiction, it has received surprisingly little attention in the debate about this issue. I claim that, as a result, an important aspect of the autonomy impairment of many addicted individuals has been largely overlooked. A widely shared assumption in the philosophical literature is that for addiction to impair a person's autonomy it has to make them (in some sense) take drugs against their will. So-called "willing addicts" are therefore usually seen as exempted from the autonomy impairment believed to characterize "unwilling addicts," the latter being those who "truly want" to stop using drugs but find their attempts repeatedly derailed by failures of self-control. In this article, I argue that the association between addiction and emotional dysregulation shows why this assumption is false. Emotional dysregulation is not only consistent with the possibility that many addicts take drugs "willingly," it supports the hypothesis that they use drugs because they truly want to. The article proposes an explanation for why emotional dysregulation should nevertheless be seen as an aspect of their loss of control and an important reason why they have impaired autonomy. I end by exploring some implications of this account for addict's decision-making capacity when they are prescribed the drugs to which they are addicted.

Using computer-based habit versus chess-based cognitive remediation training as add-on therapy to modify the imbalance between habitual behavior and cognitive control in tobacco use disorder: protocol of a randomized controlled, fMRI study

BACKGROUND

Although the vast majority of smokers are aware of the enormous preventable health hazards caused by smoking, only a small percentage of smokers manage to remain abstinent in the long term. One possible explanation for this discrepancy lies in the inflexibility of addictive behavior and associated disadvantageous decision-making. According to a dual-process theory of decision-making, two distinct decision systems can be identified. One slow deliberate system based on desirable expectations of outcome value described as goal-directed behavior and a fast reflexive system based on habitual instrumental behavior and driven by reinforcement experienced in the past. In the course of addiction development, an imbalance occurs between habitual behavior and goal-directed. The present study aims to investigate the modifiability of the balance between habitual and goal-directed behavior at the neurobiological and behavioral level in smokers using two different novel add-on therapies. We hypothesize that both interventions change the balance between goal-directed and habitual behavior, but by different mechanisms. Whereas a cognitive remediation treatment should directly improve cognitive control, in contrast an implicit priming task should affect the early processing and the emotional valence of smoking and smoking cues.

METHODS

We will conduct a randomized controlled study in treatment-seeking individuals with tobacco use disorder applying either chess-based cognitive remediation training (N = 30) or implicit computer-based habit-modifying training (N = 30) as add on therapy compared to the standard smoking cessation group therapy (N = 30) only. We will address neurobiological and neuropsychological correlates associated with craving, reward devaluation, cue reactivity and attentional bias. In addition, various effects of treatment and prediction of treatment outcome will be examined using behavioral and neural measures.

DISCUSSION

The present study will apply different examination methods such as functional magnetic resonance imaging, neuropsychological tests, and self-report before and after the interventions. This allows the identification of intervention-specific mechanisms and therefore potential neurobiology-based specific treatment targets for individuals with Tobacco Use Disorder.

TRIAL REGISTRATION

Registered at clinicaltrials.gov/ct2/show/NCT03764969 (05 December 2018).

Animals in flow - towards the scientific study of intrinsic reward in animals

The concept of flow, a state of complete absorption in an intrinsically rewarding activity, has played a pivotal role in advancing notions of human well-being beyond minimising suffering towards promoting flourishing and thriving. While flow has played a fundamental role in human positive psychology, it has not yet been explored in non-human animals, leaving an enormous void in our understanding of intrinsic motivation in animals. As ethology and related fields keep progressing in uncovering complex cognitive and affective capacities of non-human animals, we propose the time is ripe to translate the concept of flow to animals. We start by embedding flow in the topic of intrinsic motivation and describe its impact on positive human psychology and potentially positive animal welfare. We then disambiguate flow from related concepts discussed in the animal literature. Next, we derive experimental approaches in animals from the canonical characteristics of flow in humans and provide guidelines for both inducing and assessing flow by focusing on two characteristics that do not necessarily depend on self-report, namely resistance to distraction and time distortion. Not all aspects of the human flow experience are (yet) translatable, but those that are may improve quality of life in captive non-human animals.

Prevalence and factors associated with substance use among HIV positive youth attending HIV care and treatment centers in Dodoma, Tanzania

BACKGROUND

Substance use among people living with HIV is associated with poor health, social, and psychological outcomes. This study assessed the prevalence of substance use and associated factors among youth attending HIV care and treatment centers (CTCs) in Dodoma, Tanzania.

METHODS

This cross-sectional study was carried out in Dodoma, Tanzania, from February to April 2020 among youth aged 15-24 attending HIV CTCs. Data was collected using sociodemographic, WHO ASSIST Version 3.0, BDI II, and SERAD questionnaires. Data analysis was done using Stata 17. Descriptive statistics were used to summarize continuous and categorical variables. Univariable and multivariable logistic regression analyses were conducted to determine factors independently associated with substance use.

RESULTS

The prevalence of substance use was relatively low (6.6%). Older youth (20 to 24 years) were 2% less likely to use substances compared to the younger ones (15 to 19 years) (AOR: 0.07; 95% CI 0.01, 0.83). There were statistically significant decreasing odds of substance use with every year increase in age at HIV diagnosis (OR: 1.66; 95% CI 1.14, 2.41). Being unemployed was statistically significantly associated with decreased odds of substance use among this population (OR: 0.03; 95% CI 0.02, 0.33). Youth who had detectable viral loads were significantly more likely to use substances compared to those with undetectable viral loads (AOR: 12.9; 95% CI 1.07, 156.05).

CONCLUSIONS

Despite the low prevalence of substance use found in this study, it is important to note that late age of HIV diagnosis, employment, and detectable viral load negatively impacted HIV positive youth with regards to substance use. It is recommended that CTCs emphasize routine screening for substance use among youth who have detectable viral loads.

Modeling ability to resist alcohol in the human laboratory: A pilot study

Background

Roughly half of patients with alcohol use disorder prefer non-abstinence based approaches to treatment. However, only individuals who can limit their alcohol use after low-risk consumption are most likely to benefit from these approaches. This pilot study developed a laboratory-based intravenous alcohol self-administration paradigm to determine the characteristics of individuals who could successfully resist consuming alcohol after an initial exposure.

Methods

Seventeen non-treatment seeking heavy drinkers completed two versions of an intravenous alcohol self-administration paradigm designed to assess impaired control over alcohol use. In the paradigm, participants received a priming dose of alcohol and then entered a 120-min resist phase, in which they received monetary rewards if they resisted self-administering alcohol. We used Cox proportional hazards regression to determine the impact of craving and Impaired Control Scale scores on rate of lapse.

Results

64.7% of participants across both versions of the paradigm were unable to resist alcohol for the duration of the session. Craving at baseline (HR = 1.07, 95% CI 1.01-1.13, p = 0.02) and following priming (HR = 1.08, 95% CI 1.02-1.15, p = 0.01) were associated with rate of lapse. Individuals who lapsed endorsed greater attempts to control their drinking over the prior six months compared to individuals who resisted.

Conclusions

This study provides preliminary evidence that craving may be predictive of risk of lapse in individuals who are trying to limit alcohol intake after consuming a small initial amount of alcohol. Future studies should test this paradigm in a larger and more diverse sample.

Predicting the severity of internet gaming disorder with resting-state brain features: A multi-voxel pattern analysis

BACKGROUND

Internet gaming disorder (IGD) has become a worldwide mental health concern; however, the neural mechanism underlying this disorder remains unclear. Multivoxel pattern analysis (MVPA), a newly developed data-driven approach, can be used to investigate the neural features of IGD based on massive neural data.

METHODS

Resting-state fMRI data from four hundred and two participants with varying levels of IGD severity were recruited. Regional homogeneity (ReHo) and the amplitude of low-frequency fluctuation (ALFF) were calculated and subsequently decoded by applying MVPA. The highly weighted regions in both predictive models were selected as regions of interest for further graph theory and Granger causality analysis (GCA) to explore how they affect IGD severity.

RESULTS

The results revealed that the neural patterns of ReHo and ALFF can independently and significantly predict IGD severity. The highly weighted regions that contributed to both predictive models were the right precentral gyrus and left postcentral gyrus. Moreover, topological properties of the right precentral gyrus were significantly correlated with IGD severity; further GCA revealed effective connectivity from the right precentral gyrus to left precentral gyrus and dorsal anterior cingulate cortex, both of which were significantly associated with IGD severity.

CONCLUSIONS

The present study demonstrated that IGD has distinctive neural patterns, and this pattern could be found by machine learning. In addition, the neural features in the right precentral gyrus play a key role in predicting IGD severity. The current study revealed the neural features of IGD and provided a potential target for IGD interventions using brain modulation.

Neural mechanisms of brand love relationship dynamics: Is the development of brand love relationships the same as that of interpersonal romantic love relationships?

Brand love is a relationship between brands and consumers. Managing the relationship is an important issue for marketing strategy since it changes according to temporal flow. Brand love theories, including their dynamics, have been developed based on interpersonal romantic love theories. Although many brand love studies have provided useful findings, the neural mechanism of brand love remains unclear. Especially, its dynamics have not been considered from a neuroscience perspective. The present study addressed the commonalities and differentiations of activated brain regions between brand love and interpersonal romantic love relationships using a quantitative neuroimaging meta-analytic approach, from the view of brain connectivity. Regarding the mental processes of each love relationship related to these activated brain regions, decoding analysis was conducted using the NeuroQuery platform to prevent reverse inference. The results revealed that different neural mechanisms and mental processes were distinctively involved in the dynamics of each love relationship, although the anterior insula overlapped across all stages and the reinforcement learning system was driven between both love relationships in the early stage. Remarkably, regarding the distinctive mental processes, although prosocial aspects were involved in the mental processes of interpersonal romantic love relationships across all stages, they were not involved in the mental processes of brand love relationships. Conclusively, although common brain regions and mental processes between both love relationships were observed, neural mechanisms and mental processes in brand love relationship dynamics might be innately different from those in the interpersonal romantic love relationship dynamics. As this finding indicates essential distinctiveness between both these relationships, theories concerning interpersonal romantic love should be applied cautiously when investigating brand love relationship dynamics.

Boosting psychological change: Combining non-invasive brain stimulation with psychotherapy

Mental health disorders and substance use disorders are a leading cause of morbidity and mortality worldwide, and one of the most important challenges for public health systems. While evidence-based psychotherapy is generally pursued to address mental health challenges, psychological change is often hampered by non-adherence to treatments, relapses, and practical barriers (e.g., time, cost). In recent decades, Non-invasive brain stimulation (NIBS) techniques have emerged as promising tools to directly target dysfunctional neural circuitry and promote long-lasting plastic changes. While the therapeutic efficacy of NIBS protocols for mental illnesses has been established, neuromodulatory interventions might also be employed to support the processes activated by psychotherapy. Indeed, combining psychotherapy with NIBS might help tailor the treatment to the patient's unique characteristics and therapeutic goal, and would allow more direct control of the neuronal changes induced by therapy. Herein, we overview emerging evidence on the use of NIBS to enhance the psychotherapeutic effect, while highlighting the next steps in advancing clinical and research methods toward personalized intervention approaches.

Prefrontal cortical response to natural rewards and self-reported anhedonia are associated with greater craving among recently withdrawn patients in residential treatment for opioid use disorder

Both anhedonia and craving are common among patients with opioid use disorder (OUD), and are associated with vulnerability to relapse. Although these constructs are theoretically linked relatively few studies have examined them together. In the current study, recently withdrawn patients (N = 71) in residential treatment for prescription OUD underwent a cue reactivity paradigm while being monitored with functional near-infrared spectroscopy (fNIRS). Patients also self-reported symptoms of anhedonia via the Snaith-Hamilton Pleasure Scale (SHAPS), while smartphone-based ecological momentary assessments (EMA) were used to measure craving levels. On average, lower right prefrontal cortex (PFC) activity in response to positive social stimuli was associated with higher craving (β = - 2.87; S.E. = 1.23; p = 0.02). Self-reported anhedonia moderated the association between PFC activity and craving (β = - 1.02; S.E. = 0.48; p = 0.04), such that patients with two or more anhedonic symptoms had a significant and stronger negative association between PFC activation to hedonically positive images and craving, compared to patients with fewer than two anhedonic symptoms, among whom the association was not significant. This finding provides evidence that higher levels of anhedonia among patients in residential treatment for OUD are associated with a stronger link between lower PFC response to positive social experiences and higher levels of craving, potentially increasing overall vulnerability to relapse.

Association between empathy and drinking among a community sample of heavy drinkers: Sex differences and neural correlates

Alcohol use disorder (AUD) is a major health problem, yet most individuals with AUD do not perceive a need for formal treatment and do not receive treatment. The lack of treatment seeking among individuals with AUD may suggest a lack of self-awareness and insight into the seriousness of AUD related problems, as well as lack of empathy for the impact of one's drinking on others. Recent work has suggested that empathy may be impaired among individuals seeking treatment for AUD. Further these impairments may differ by sex such that males with lower empathy reported more drinking consequences and greater drinking intensity, but there was no association between empathy and drinking among females. The current study used regression analyses (alpha = 0.05) to examine the association between empathy (as measured by the four scales of the Interpersonal Reactivity Index), independent components of gray matter volume in regions associated with empathy, and drinking variables among non-treatment seeking drinkers with AUD (N = 136) and also examined these effects by sex. Results showed greater perspective taking was associated with less temporoparietal and frontotemporal gray matter volume (B(SE) = -0.912 (0.043), p = 0.034). An interaction between perspective taking and sex was associated with craving, such that higher perspective taking was associated with less craving for males only (B(SE) = -0.48 (0.243), p = 0.049; R2 = 0.087). Empathic concern was related to lower percent heavy drinking days for both males and females (B(SE) = -1.57 (0.743), p = 0.035; R2 = 0.11). The current study found empathy may be an important predictor of craving for males and frequency of heavy drinking for males and females. Future work should investigate whether empathy predicts treatment seeking.

Approaches to Medication Administration in Patients With Lack of Insight

Lack of insight typically complicates psychiatric presentations, necessitating careful thought and planning to choose the best course of treatment. Exploring methods of medication administration techniques in the context of a lack of insight is crucial to achieving the ultimate goal of overcoming the insight barrier as rapidly as possible, which will result in therapeutic benefit. This study's objective was to systematically review the evidence on medication administration techniques in a backdrop of lack of insight and how that evidence was curated in the scientific literature. This study used the literature search strategy, which entails retrieving and analyzing the existing scientific literature pertinent to medication administration techniques for individuals with no insight between 2010 and 2022. Accessing online databases, such as PubMed, Google Scholar, and Medline was utilized in this study's literature search strategy. In our findings, in the primary evidence search, no randomized control trial (RCT) comparing the various models of medication administration with a lack of insight was found. No study provided data on the superiority of utility, quality of life, or efficacy outcome. Some 17 scientific papers were identified that cited various trials about lack of insight and medication use and met the inclusion criteria. We concluded that it could be challenging to administer medication to patients who lack insight.

Nonetheless, progress has been made to mitigate this obstacle. Common moral values, common sense, medicolegal support, person-centered integrated care, and cutting-edge medication techniques may play a role. However, these models of medication administration are still evolving, along with the ethical concerns accompanying them. Hopefully, the available models discussed in this analysis will serve as a foundation for future developments. Nonetheless, much remains to be done. We encourage contemporary research to investigate safer and more dynamic methods that can alleviate this condition.

Comparison of Neural Correlates of Reactive Inhibition in Cocaine, Heroin, and Polydrug Users through a Contextual Go/No-Go Task Using Event-Related Potentials

Simple Summary

Witnessing the current increase in the use of substances in society and considering the associated pervasive relapse rate, the management of addictions remains a significant challenge. The identification of biomarkers that are linked to specific profiles of consumption would allow a more targeted, and therefore, more effective care. In this view, the present study evaluates and compares the cognitive performance usually associated with substance use disorder—inhibitory control, attentional bias, and error detection—of heroin, cocaine, and polydrug users to matched healthy controls. Simultaneously, the addition of measurement of the modulation of brain activity during the task (event-related potentials technique) offers a reliable representation of the neuronal mechanisms underlying cognitive functioning. The results reveal substance-specific neural patterns of response, notably a more deleterious impact on polydrug use, and, despite nonsignificant results, suggest a more drastically affected cognitive functioning in cocaine users. Such evidence refines our knowledge of the specific mode of action of each substance. Ultimately, knowing their neural signature will lead to the implementation of more targeted interventions, thereby allowing specific needs to be addressed.

Abstract

Recent global data indicates a worldwide increase in polydrug use associated with a shift from recreational to productive habits of consumption. Such non-responsible abuse of substances (alcohol, cocaine, heroin, etc.) is likely to lead to addictive disorders that are characterized by various neuropsychopharmacological effects. A main cognitive function involved in the onset and long-term maintenance of addiction is reactive inhibition, i.e., the ability to withhold a prepotent motor dominant response. In the present study, 63 (poly)drug user patients who were undergoing a detoxification program, in addition to 19 healthy controls matched for gender, age, and education, were subjected to a “contextual Go/No-Go task” with concomitant electroencephalography. Stimuli were superimposed on three contextual backgrounds: control (black screen), drug-unrelated (neutral pictures), or drug-related (pictures related to drug consumption). Of these patients, 23 were cocaine users (CU), 21 were heroin users (HU), and 19 were polydrug users (PDU). The main results showed that (1) at the behavioral level, more commission errors occurred with the PDU patients compared to the healthy controls; (2) at the neurophysiological level, specific alterations were found on classical event-related potentials that index reactive inhibition. Indeed, the higher rate of errors in the PDU group was subtended by both reduced amplitude and latency on the ∆N2 component and increased ∆P3 latency compared to controls. These data clearly suggest a more deleterious impact of polydrug use on inhibitory functions. In addition, our results provide evidence of reduced ERN amplitude in cocaine users, suggesting that impaired performance monitoring and error-processing may support impaired awareness, thereby preventing these patients from changing their behaviors.

Neurophysiological Deficits During Reappraisal of Negative Emotional Stimuli in Opioid Misuse

BACKGROUND

Opioid misuse is hypothesized to compromise the ability to regulate negative emotions, as manifested through visceral and peripheral physiological signals. However, neurophysiological impairment of top-down cognitive emotion regulation in opioid misuse has not previously been shown.

METHODS

Patients with chronic pain who had been taking opioids for 90 days or longer (N = 149; female, n = 98) underwent a negative emotion regulation task with electroencephalography. Participants were instructed to view or reappraise negative images presented for 3 seconds. Using a validated cutoff score on the Current Opioid Misuse Measure, participants were classified as exhibiting aberrant drug-related behavior consistent with opioid misuse (MISUSE+) or as being low risk for opioid misuse (MISUSE-). Participants reported their craving in response to negative emotions over the past week.

RESULTS

We observed a group × condition interaction (p = .003) such that the MISUSE- group decreased the late positive potential of the electroencephalography during reappraisal, whereas the MISUSE+ group showed increased late positive potential during reappraisal. This deficit in negative emotion regulation remained significant after controlling for an array of potential confounding variables, including opioid dose, pain, and depression. Heightened late positive potential during reappraisal was associated with more severe opioid craving.

CONCLUSIONS

Opioid misuse may occasion top-down deficits in emotional regulation that begin as early as 400 ms after presentation of negative stimuli. It remains unknown whether emotion dysregulation is the cause, correlate, or consequence of opioid misuse. Nonetheless, targeting emotion dysregulation in opioid misuse with reappraisal-focused interventions may represent an important treatment approach.

Development of a classifier for gambling disorder based on functional connections between brain regions

AIM

Recently, a machine-learning (ML) technique has been used to create generalizable classifiers for psychiatric disorders based on information of functional connections (FCs) between brain regions at resting state. These classifiers predict diagnostic labels by a weighted linear sum (WLS) of the correlation values of a small number of selected FCs. We aimed to develop a generalizable classifier for gambling disorder (GD) from the information of FCs using the ML technique and examine relationships between WLS and clinical data.

METHODS

As a training dataset for ML, data from 71 GD patients and 90 healthy controls (HCs) were obtained from two magnetic resonance imaging sites. We used an ML algorithm consisting of a cascade of an L1-regularized sparse canonical correlation analysis and a sparse logistic regression to create the classifier. The generalizability of the classifier was verified using an external dataset. This external dataset consisted of six GD patients and 14 HCs, and was collected at a different site from the sites of the training dataset. Correlations between WLS and South Oaks Gambling Screen (SOGS) and duration of illness were examined.

RESULTS

The classifier distinguished between the GD patients and HCs with high accuracy in leave-one-out cross-validation (area under curve (AUC = 0.89)). This performance was confirmed in the external dataset (AUC = 0.81). There was no correlation between WLS, and SOGS and duration of illness in the GD patients.

CONCLUSION

We developed a generalizable classifier for GD based on information of functional connections between brain regions at resting state.

Clinical insight level predicts successful quit or control attempts during the first three months of outpatient addiction treatment

INTRODUCTION

Low clinical insight in psychiatry is defined as poor recognition of one's mental illness, including disability to self-evaluate symptom severity. It has been reported as common in addiction and is associated with lower treatment compliance. Longitudinal studies suggest that low clinical insight could be linked to more relapse. However, association with successful quit attempts remains unknown.

OBJECTIVE

Our objective was to examine the prospective link between baseline clinical insight level and self-reports of successful attempts to quit / control use during the first 3 months of outpatient addiction treatment.

METHODS

Participants were recruited from the ADDICTAQUI cohort at outpatient treatment intake for substance or behavioral addictions. They completed a baseline evaluation using the Addiction Severity Index (ASI), the Mini International Neuropsychiatric Interview (MINI), and the modified Hanil Alcohol Insight Scale (m-HAIS) with a follow-up ASI 3 months later. Data were analyzed using multiple logistic regression and non-parametric tests.

RESULTS

Lower clinical insight level at baseline was associated with less successful quit / control attempts during the first 3 months of outpatient treatment compared to a higher clinical insight level, controlling for sociodemographic factors, baseline addiction severity, and comorbidities (n = 54; exp(B) = 0.76; p (FDRcor) = 0.033).

CONCLUSION

Poor clinical insight may be a barrier to treatment success, and future studies should examine underlying mechanisms.

Is addiction a brain disease? A plea for agnosticism and heterogeneity

RATIONALE

Although increasingly subject to criticism, the brain disease model of addiction (BDMA) remains dominant within addiction science. Yet few advocates or critics of the BDMA have provided an account of what a brain disease is. The aim of this review is to conceptually clarify what it would mean for the BDMA to be true, rather than to argue decisively for or against it.

OBJECTIVES

Conceptual clarification of the BDMA requires consideration of possible models of disease and their relationship to the BDMA. A barrier to such consideration is belief that the BDMA is necessary to combatting addiction stigma. To address this barrier, I begin with discussion of what we know about the effects of the brain disease label on addiction stigma, and why labelling effects should have no bearing on the validity of the BDMA. I then distinguish strong, minimal, network, and mismatch models of disease, and I argue that the BDMA aligns with a strong disease model. This means that underlying brain pathology is hypothesized to be the cause of the personal-level observable signs and experienced symptoms characteristic of addiction. Evaluation of the BDMA therefore requires analysis of the concepts of brain dysfunction and causation, and their application to addiction science.

RESULTS

Brain dysfunction cannot be analyzed merely as brain changes or brain differences; nor can it be inferred merely from the presence of personal-level signs and symptoms. It is necessary to have an account of normal brain function by which to measure it. The theoretical and empirical challenges to developing such an account are not insurmountable, but they are substantial. Although there exist competing analyses of causation, there is a relatively standard method used to establish it within experimental science: intervention. Using this method, the causal significance of brain states, such as, e.g., extensive gray matter loss and/or neuroadapations in the mesocorticolimbic dopamine system, is not yet fully demonstrated. Further studies are necessary to determine their effect compared with other possible variables, such as, e.g., alternative reinforcers.

CONCLUSIONS

Conceptual clarification and preliminary empirical assessment of the BDMA recommends agnosticism about its validity and an openness to heterogeneity; in some cases addiction may be a brain disease, in others not. Either way, addiction stigma can be combatted by fighting moralism about drugs and moralistic drug policies directly, as opposed to resting hopes on the brain disease label.

Relationship between levels of mindfulness and substance use pattern

ABSTRACT Objective Evaluate the association between levels of mindfulness and sociodemographic characteristics and pattern of drug use of individuals seeking treatment in a University Service Specialized in Substance Use Disorders. Methods This is a cross-sectional study with 164 individuals over 18 years of age seeking treatment for the use of psychoactive substances in the June 2018-December 2019 period, using a questionnaire for sociodemographic data, the Mindful Attention Awareness Scale (MAAS) self-reporting instrument, and the Alcohol, Smoking, and Substance Involvement Screening Test. Results An association was found between low levels of mindfulness mainly with the individual risk of being a medium/high-risk user of sedative-hypnotic drugs (p = 0.020). A borderline association was also found between MAAS and the risk of the individual being a medium/high risk of alcohol (p = 0.053) and with a more severe pattern of substance use (p = 0.065). Conclusion Individuals seeking treatment for substance use presented impairments in the attentional aspect of mindfulness and levels of mindfulness seem to protect against behaviors related to substance use, especially against the use of high/moderate risk of sedative-hypnotics.

Recreational drug use and prospective memory

Prospective memory (PM) impairment in recreational drug users has been documented in recent years. However, most studies on the effects of drugs on PM contain several methodological challenges, such as small sample size (< 100 participants), unrepresentative sample type (e.g., student or patient), short abstinence period (< 7 days), and lack of control of potential confounds (e.g., sleep and IQ). The present study investigated the possible consequences of recreational drug use on prospective memory, using self-report and lab-based prospective memory measures while overcoming the methodological challenges. The sample was composed of 47 non-users (27 females, age range from 18 to 50 +) and 53 drug users (21 females, age range from 18 to 50 +). Recreational drug users reported significantly more deficits in the long-term episodic, short-term habitual, and internally cued PM failures subscales of the Prospective Memory Questionnaire. However, these deficits were eliminated after controlling for covariates (e.g., age, sleep quality, general health, alcohol usage). Recreational drug users also performed worse than non-users in the short-term, long-term, event-based, and time-based PM subscales of the Royal Prince Alfred Prospective Memory Test. These results remained significant after controlling for the covariates. Drug users demonstrated greater impairments on time-based and long-term PM tasks thought to be linked with executive functioning. Taken together, the present study provides further support for recreational drug-related deficits in PM and highlights a dissociation between self-report and lab-based PM measures.

At the heart of the interoception network: Influence of the parasubthalamic nucleus on autonomic functions and motivated behaviors

The parasubthalamic nucleus (PSTN), a small nucleus located on the lateral edge of the posterior hypothalamus, has emerged in recent years as a highly interconnected node within the network of brain regions sensing and regulating autonomic function and homeostatic needs. Furthermore, the strong integration of the PSTN with extended amygdala circuits makes it ideally positioned to serve as an interface between interoception and emotions. While PSTN neurons are mostly glutamatergic, some of them also express neuropeptides that have been associated with stress-related affective and motivational dysfunction, including substance P, corticotropin-releasing factor, and pituitary adenylate-cyclase activating polypeptide. PSTN neurons respond to food ingestion and anorectic signals, as well as to arousing and distressing stimuli. Functional manipulation of defined pathways demonstrated that the PSTN serves as a central hub in multiple physiologically relevant networks and is notably implicated in appetite suppression, conditioned taste aversion, place avoidance, impulsive action, and fear-induced thermoregulation. We also discuss the putative role of the PSTN in interoceptive dysfunction and negative urgency. This review aims to synthesize the burgeoning preclinical literature dedicated to the PSTN and to stimulate interest in further investigating its influence on physiology and behavior.

Psychedelic-Assisted Therapy for Substance Use Disorders and Potential Mechanisms of Action

Substance use disorders (SUD) represent a significant public health issue with a high need for novel and efficacious treatment options. In light of this high unmet need, recent results reporting beneficial outcomes of psychedelic-assisted therapy in SUD are particularly relevant. However, several questions remain with regard to this treatment approach. The clinical mechanisms of action of psychedelic substances in the treatment of SUD are not well understood. Closing this knowledge gap is critical to inform and optimize the psychotherapeutic embedding of the acute substance administration. In this chapter, we discuss potential mechanisms that have implications on psychotherapeutic approaches including induced neuroplasticity, alterations in brain network connectivity, reward and emotion processing, social connectedness, insight, and mystical experiences. Furthermore, we outline considerations and approaches that leverage these mechanisms in order to optimize the therapeutic embedding by maximizing synergy between substance effects and psychotherapy. Understanding the mechanisms of action, developing psychotherapeutic approaches accordingly, and evaluating their synergistic efficacy in scientific studies will be critical to advance the framework of psychedelic-assisted therapy for addiction, create evidence-based approaches, and achieve the best treatment outcome for patients with SUD.

Cognitive behavioural group therapy with mindfulness for kleptomania: an open trial

Kleptomania is an addiction to stealing without an economic motive; therefore, an examination of effective interventions as a preventive measure is needed. The effectiveness of cognitive behavioural therapy (CBT) combined with mindfulness for the treatment of addiction has been previously indicated, and it is presumed to be effective for kleptomania; however, this relationship remains unstudied. Therefore, this study aimed to examine the effectiveness of cognitive behavioural group therapy (CBGT) combined with mindfulness for treating kleptomania. The results of a 12-session programme of CBGT combined with mindfulness for 22 patients with kleptomania showed that kleptomania symptoms and quality of life (QOL) improved. Furthermore, the recovery process revealed that the improvement of distress tolerance affected the improvement of kleptomania symptoms and that the improvement of reward perception and distress tolerance affected the improvement of stress response and QOL. These results suggest that CBGT combined with mindfulness may be effective in improving symptoms and QOL in kleptomania.

Key learning aims

(1)

Common and gender-specific associations with cocaine use on gray matter volume: Data from the ENIGMA addiction working group

Gray matter volume (GMV) in frontal cortical and limbic regions is susceptible to cocaine-associated reductions in cocaine-dependent individuals (CD) and is negatively associated with duration of cocaine use. Gender differences in CD individuals have been reported clinically and in the context of neural responses to cue-induced craving and stress reactivity. The variability of GMV in select brain areas between men and women (e.g., limbic regions) underscores the importance of exploring interaction effects between gender and cocaine dependence on brain structure. Therefore, voxel-based morphometry data derived from the ENIGMA Addiction Consortium were used to investigate potential gender differences in GMV in CD individuals compared to matched controls (CTL). T1-weighted MRI scans and clinical data were pooled from seven sites yielding 420 gender- and age-matched participants: CD men (CDM, n = 140); CD women (CDW, n = 70); control men (CTLM, n = 140); and control women (CTLW, n = 70). Differences in GMV were assessed using a 2 × 2 ANCOVA, and voxelwise whole-brain linear regressions were conducted to explore relationships between GMV and duration of cocaine use. All analyses were corrected for age, total intracranial volume, and site. Diagnostic differences were predominantly found in frontal regions (CD < CTL). Interestingly, gender × diagnosis interactions in the left anterior insula and left lingual gyrus were also documented, driven by differences in women (CDW < CTLW). Further, lower right hippocampal GMV was associated with greater cocaine duration in CDM. Given the importance of the anterior insula to interoception and the hippocampus to learning contextual associations, results may point to gender-specific mechanisms in cocaine addiction.

Increased network centrality of the anterior insula in early abstinence from alcohol

Abnormal resting‐state functional connectivity, as measured by functional magnetic resonance imaging (MRI), has been reported in alcohol use disorders (AUD), but findings are so far inconsistent. Here, we exploited recent developments in graph‐theoretical analyses, enabling improved resolution and fine‐grained representation of brain networks, to investigate functional connectivity in 35 recently detoxified alcohol dependent patients versus 34 healthy controls. Specifically, we focused on the modular organization, that is, the presence of tightly connected substructures within a network, and on the identification of brain regions responsible for network integration using an unbiased approach based on a large‐scale network composed of more than 600 a priori defined nodes. We found significant reductions in global connectivity and region‐specific disruption in the network topology in patients compared with controls. Specifically, the basal brain and the insular–supramarginal cortices, which form tightly coupled modules in healthy subjects, were fragmented in patients. Further, patients showed a strong increase in the centrality of the anterior insula, which exhibited stronger connectivity to distal cortical regions and weaker connectivity to the posterior insula. Anterior insula centrality, a measure of the integrative role of a region, was significantly associated with increased risk of relapse. Exploratory analysis suggests partial recovery of modular structure and insular connectivity in patients after 2 weeks. These findings support the hypothesis that, at least during the early stages of abstinence, the anterior insula may drive exaggerated integration of interoceptive states in AUD patients with possible consequences for decision making and emotional states and that functional connectivity is dynamically changing during treatment.

HIV infection is linked with reduced error-related default mode network suppression and poorer medication management abilities

OBJECTIVE

Brain activity linked with error processing has rarely been examined among persons living with HIV (PLWH) despite importance for monitoring and modifying behaviors that could lead to adverse health outcomes (e.g., medication non-adherence, drug use, risky sexual practices). Given that cannabis (CB) use is prevalent among PLWH and impacts error processing, we assessed the influence of HIV serostatus and chronic CB use on error-related brain activity while also considering associated implications for everyday functioning and clinically-relevant disease management behaviors.

METHODS

A sample of 109 participants, stratified into four groups by HIV and CB (HIV+/CB+, n = 32; HIV+/CB-, n = 27; HIV-/CB+, n = 28; HIV-/CB-, n = 22), underwent fMRI scanning while completing a modified Go/NoGo paradigm called the Error Awareness Task (EAT). Participants also completed a battery of well-validated instruments including a subjective report of everyday cognitive failures and an objective measure of medication management abilities.

RESULTS

Across all participants, we observed expected error-related anterior insula (aI) activation which correlated with better task performance (i.e., less errors) and, among HIV- participants, fewer self-reported cognitive failures. Regarding awareness, greater insula activation as well as greater posterior cingulate cortex (PCC) deactivation were notably linked with aware (vs. unaware) errors. Regarding group effects, unlike HIV- participants, PLWH displayed a lack of error-related deactivation in two default mode network (DMN) regions (i.e., PCC, medial prefrontal cortex [mPFC]). No CB main or interaction effects were detected. Across all participants, reduced error-related PCC deactivation correlated with reduced medication management abilities and PCC deactivation mediated the effect of HIV on such abilities. More lifetime CB use was linked with reduced error-related mPFC deactivation among HIV- participants and poorer medication management across CB users.

CONCLUSIONS

These results demonstrate that insufficient error-related DMN suppression linked with HIV infection, as well as chronic CB use among HIV- participants, has real-world consequences for medication management behaviors. We speculate that insufficient DMN suppression may reflect an inability to disengage task irrelevant mental operations, ultimately hindering error monitoring and behavior modification.

Affective Neuroscience Contributions to the Treatment of Addiction: The Role of Social Instincts, Pleasure and SEEKING

Addiction is an illness prevalent in the worldwide population that entails multiple health risks. Because of the nature of addictive disorders, users of drugs seldom look for treatment and when they do, availability can be difficult to access. Permanence in treatment and its outcomes vary from case to case. Most models work from a multidisciplinary approach that tackles several dimensions of addictive disorders. However, the different etiological factors claim for a personalized treatment to enhance opportunities for better results. Problems in relationships with others play an important role in the etiology and the recovery process of addiction. This paper focuses on the social-environmental causes of addiction based on an affective neuroscience approach that attempts to integrate the interplay between social instincts, pleasure, and the SEEKING system in addiction. To advance toward better treatment strategies, it is pertinent to understand the limitations of the current multidisciplinary models. Acknowledging the social nature of the human brain may help to identify the quality of different types of traumatic early life experiences in drug users and how to address them in what may become a neuropsychoanalytic treatment of addiction.

The Assessment of Food Addiction and the Yale Food Addiction Scale in Bariatric Surgery Populations

Food addiction (FA) appears among bariatric weight loss surgery candidates who struggle to control the intake of hyperpalatable/refined foods have high rates of psychopathology and related health problems. Despite this, prevalence rates of FA in the bariatric sector are reported as low or variable. We investigated the prevalence of FA and the applicability of conventionally used metrics for 166 pre-surgery candidates from a weight management centre (USA) and a major metropolitan hospital (Australia). Self-report measures assessed FA (Yale Food Addiction Scale (YFAS)), body mass index (BMI), disordered eating, addictive personality, psychopathology, and diet. Consistent with prior research, standard YFAS scoring, requiring the endorsement of a distress/impairment (D/I) criterion (FA + D/I), yielded a FA prevalence rate of 12.7%, compared to 37.3% when D/I was omitted (FA − D/I). We compared profiles for those with FA using each scoring method against those ‘without’, who did not meet a minimum of three YFAS symptoms (non-FA ≤ 2). Both methods differentiated those with and without FA on addictive traits, disordered eating and hyperpalatable food consumption. Only FA + D/I differentiated markers of psychological distress or impairment, including depression, anxiety and quality of life. Results indicate a need for further FA research in bariatric settings.

NOP receptor antagonism attenuates reinstatement of alcohol-seeking through modulation of the mesolimbic circuitry in male and female alcohol-preferring rats

In patients suffering from alcohol use disorder (AUD), stress and environmental stimuli associated with alcohol availability are important triggers of relapse. Activation of the nociceptin opioid peptide (NOP) receptor by its endogenous ligand Nociceptin/Orphanin FQ (N/OFQ) attenuates alcohol drinking and relapse in rodents, suggesting that NOP agonists may be efficacious in treating AUD. Intriguingly, recent data demonstrated that also blockade of NOP receptor reduced alcohol drinking in rodents. To explore further the potential of NOP antagonism, we investigated its effects on the reinstatement of alcohol-seeking elicited by administration of the α2 antagonist yohimbine (1.25 mg/kg, i.p.) or by environmental conditioning factors in male and female genetically selected alcohol-preferring Marchigian Sardinian (msP) rats. The selective NOP receptor antagonist LY2817412 (0.0, 3.0, 10.0, and 30.0 mg/kg) was first tested following oral (p.o.) administration. We then investigated the effects of LY2817412 (1.0, 3.0, 6.0 μg/μl/rat) microinjected into three candidate mesolimbic brain regions: the ventral tegmental area (VTA), the central nucleus of the amygdala (CeA), and the nucleus accumbens (NAc). We found that relapse to alcohol seeking was generally stronger in female than in male rats and oral administration of LY2817412 reduced yohimbine- and cue-induced reinstatement in both sexes. Following site-specific microinjections, LY2817412 reduced yohimbine-induced reinstatement of alcohol-seeking when administered into the VTA and the CeA, but not in the NAc. Cue-induced reinstatement was suppressed only when LY2817412 was microinjected into the VTA. Infusions of LY2817412 into the VTA and the CeA did not alter saccharin self-administration. These results demonstrate that NOP receptor blockade prevents the reinstatement of alcohol-seeking through modulation of mesolimbic system circuitry, providing further evidence of the therapeutic potential of NOP receptor antagonism in AUD.

Addiction Research Unit: Affective and cognitive mechanisms of specific Internet-use disorders

In the eleventh International Classification of Diseases (ICD-11) of the World Health Organization, gambling disorder and gaming disorder are included in the category 'disorders due to addictive behaviours', which can be specified further as occurring either predominantly offline or predominantly online. Other specific problematic behaviours may be considered for the category 'other specified disorders due to addictive behaviours'. The Research Unit FOR 2974, funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG), focuses on the most prominent online addictive behaviours: gaming, pornography use, buying-shopping and social-networks use. The main goal of the Research Unit is to contribute to a better understanding of the common and differential psychological as well as neurobiological mechanisms involved in these specific types of Internet-use disorders. We aim to investigate theoretically argued (bio)psychological processes with a focus on concepts coming from research of substance-use disorders, for example, cue reactivity and craving, executive functions and specific inhibitory control, coping, implicit cognitions, and decision making. One central characteristic of the Research Unit is that we will investigate all participants using a comprehensive core battery of experimental paradigms, neuropsychological tasks, questionnaires, biomarkers, ambulatory assessment, and a 6-month follow-up survey. Beyond the anticipated contributions to the scientific understanding of the mechanisms involved in the development and maintenance of respective online addictive behaviours, we also expect contributions to clinical practice by showing which affective and cognitive mechanisms may be addressed more intensively to optimize treatment.

Atypical interoception as a common risk factor for psychopathology: A review

The inadequacy of a categorial approach to mental health diagnosis is now well-recognised, with many authors, diagnostic manuals and funding bodies advocating a dimensional, trans-diagnostic approach to mental health research. Variance in interoception, the ability to perceive one's internal bodily state, is reported across diagnostic boundaries, and is associated with atypical functioning across symptom categories. Drawing on behavioural and neuroscientific evidence, we outline current research on the contribution of interoception to numerous cognitive and affective abilities (in both typical and clinical populations), and describe the interoceptive atypicalities seen in a range of psychiatric conditions. We discuss the role that interoception may play in the development and maintenance of psychopathology, as well as the ways in which interoception may differ across clinical presentations. A number of important areas for further research on the role of interoception in psychopathology are highlighted.