Clinical and Neural Correlates of Reward and Relief Drinking

Cognitive inflexibility moderates the relationship between relief-driven drinking motives and alcohol use

Introduction

Drinking motives and neurocognition play significant roles in predicting alcohol use. There is limited research examining how relief-driven drinking motives interact with neurocognition in alcohol use, which would help to elucidate the neurocognitive-motivational profiles most susceptible to harmful drinking. This study investigated the interactions between neurocognition (response inhibition and cognitive flexibility) and relief-driven drinking, in predicting problem drinking.

Methods

Participants completed the Alcohol Use Disorders Identification Test - Consumption items (AUDIT-C) to measure drinking behaviour, and online cognitive tasks, including the Value-Modulated Attentional Capture and Reversal Task (VMAC-R) and the Stop Signal Task (SST). The sample (N = 368) were individuals who drink alcohol, which included a subsample (N = 52) with problematic drinking, as defined by self-identifying as having a primary drinking problem. Drinking motives were assessed using a binary coping question in the overall sample, and the Habit, Reward, and Fear Scale (HRFS) in the subsample. Moderation analyses were conducted to investigate whether cognitive flexibility and response inhibition moderated relationships between relief-driven motives and drinking.

Results

Cognitive flexibility moderated the relationship between relief-driven motives and drinking (overall sample: β = 13.69, p = 0.017; subsample: β = 1.45, p = 0.013). Greater relief-driven motives were associated with heavier drinking for individuals with low cognitive flexibility. There was no significant interaction between response inhibition and relief-driven motives.

Conclusions

Relief-driven drinking motives interact with cognitive inflexibility to drive heavier drinking. Greater understanding of these neurocognitive-motivational mechanisms may help to develop more targeted and effective interventions for reducing harmful drinking.

Neural correlates of the addictions neuroclinical assessment (ANA) incentive salience factor among individuals with alcohol use disorder

The Addictions Neuroclinical Assessment (ANA) is a recently-developed framework offering a more holistic understanding of three neurofunctional and behavioral domains that reflect the neurobiological dysfunction seen in alcohol use disorder (AUD). While the ANA domains have been well-validated across independent laboratories, there is a critical need to identify neural markers that subserve the proposed neurofunctional domains. The current study involves secondary data analysis of a two-week experimental medication trial of ibudilast (50 mg BID). Forty-five non-treatment-seeking participants with AUD (17F / 28 M) completed a battery of validated behavioral assessments forming the basis of their incentive salience factor score, computed via factor analysis, as well as a functional neuroimaging (fMRI) task assessing their neural reactivity to visual alcohol cues after being on placebo or ibudilast for 7 days. General linear models were conducted to examine the relationship between incentive salience and neural alcohol cue-reactivity in the ventral and dorsal stratum. Whole-brain generalized linear model analyses were conducted to examine associations between neural alcohol cue-reactivity and incentive salience. Age, sex, medication, and smoking status were included as covariates. Incentive salience was not associated with cue-elicited activation in the dorsal or ventral striatum. Incentive salience was significantly positively correlated (p < 0.05) with alcohol cue-elicited brain activation in reward-learning and affective regions including the insula and posterior cingulate cortices, bilateral precuneus, and bilateral precentral gyri. The ANA incentive salience factor is reflected in brain circuitry important for reward learning and emotion processing. Identifying a sub-phenotype of AUD characterized by increased incentive salience to alcohol cues allows for precision medicine approaches, i.e. treatments specifically targeting craving and reward from alcohol use. This study serves as a preliminary bio-behavioral validation for the incentive salience factor of the ANA. Further studies validating the neural correlates of other ANA factors, as well as replication in larger samples, appear warranted.

Longitudinal stability of reward and relief drinking phenotypes in community and treatment-seeking individuals who engage in heavy drinking

BACKGROUND

Precision medicine approaches aim to improve treatment outcomes by identifying which treatments work best for specific individual phenotypes. In the treatment of alcohol use disorder (AUD), precision medicine approaches have been proposed based on phenotypes characterized by individuals who drink primarily to enhance rewarding experiences (i.e., reward drinking) or those who drink primarily to relieve negative states (i.e., relief drinking). This study examined these phenotypes across treatment- and nontreatment-seeking individuals and the stability of the phenotypes over time.

METHODS

We used latent profile and latent transition analyses to identify and assess longitudinal stability (over 3 or 4 months) of reward and relief drinking subgroups within a nontreatment-seeking community sample that engaged in hazardous drinking (n = 189) and two treatment-seeking samples of individuals with AUD enrolled in two large clinical trials (n = 1726, n = 1383). We examined prospective associations with alcohol consumption and consequences at long-term follow-up (15 or 18 months).

RESULTS

Results supported four subgroups: low reward/low relief, low reward/high relief, high reward/low relief, and high reward/high relief. The community sample contained more individuals classified within the high reward/low relief subgroup than treatment-seeking samples. Subgroups were generally more stable over time in the community sample than in the treatment-seeking samples. Alcohol consumption and consequences decreased over time for the treatment-seeking samples, with consequences and drinking frequency decreasing for the community sample. Participants classified within the high reward/high relief and low reward/high relief groups reported the most consequences and consumption at long-term follow-up.

CONCLUSION

Reward and relief drinking phenotypes can be identified within community and treatment-seeking samples of individuals who drink heavily. The phenotypic subgroups appear to be stable over time in the absence of treatment, change somewhat during treatment, and provide utility in predicting alcohol consumption and consequences.

Elevated Amygdala Responses During De Novo Pavlovian Conditioning in Alcohol Use Disorder Are Associated With Pavlovian-to-Instrumental Transfer and Relapse Latency

Background

Contemporary learning theories of drug addiction ascribe a key role to Pavlovian learning mechanisms in the development, maintenance, and relapse of addiction. In fact, cue-reactivity research has demonstrated the power of alcohol-associated cues to activate the brain's reward system, which has been linked to craving and subsequent relapse. However, whether de novo Pavlovian conditioning is altered in alcohol use disorder (AUD) has rarely been investigated.

Methods

To characterize de novo Pavlovian conditioning in AUD, 62 detoxified patients with AUD and 63 matched healthy control participants completed a Pavlovian learning task as part of a Pavlovian-to-instrumental transfer paradigm during a functional magnetic resonance imaging session. Patients were followed up for 12 months to assess drinking behavior and relapse status.

Results

While patients and healthy controls did not differ in their ability to explicitly acquire the contingencies between conditioned and unconditioned stimuli, patients with AUD displayed significantly stronger amygdala responses toward Pavlovian cues, an effect primarily driven by stronger blood oxygen level-dependent differentiation during learning from reward compared with punishment. Moreover, in patients compared with controls, differential amygdala responses during conditioning were positively related to the ability of Pavlovian stimuli to influence ongoing instrumental choice behavior measured during a subsequent Pavlovian-to-instrumental transfer test. Finally, patients who relapsed within the 12-month follow-up period showed an inverse association between amygdala activity during conditioning and relapse latency.

Conclusions

We provide evidence of altered neural correlates of de novo Pavlovian conditioning in patients with AUD, especially for appetitive stimuli. Thus, heightened processing of Pavlovian cues might constitute a behaviorally relevant mechanism in alcohol addiction.

Predictors of polysubstance use in patients with severe alcohol use disorder: the role of reward craving

BACKGROUND

Different craving typologies (i.e., reward, relief, obsessive) have been identified in alcohol use disorder (AUD) but have been less investigated in specific populations like AUD patients with polysubstance use (PSU). The role of dysfunctional personality traits and reward pathways has been reported in both AUD and PSU. We hypothesized that patients with AUD-PSU might show a prevalent reward craving, alongside specific sociodemographic, clinical, and personality features, and aimed at investigating differences in 423 severe AUD outpatients with and without PSU.

METHODS

One hundred fifteen patients (27.1% of the sample, 67% males, 42 ± 11.6 years old) displayed PSU. Sociodemographic, clinical features and psychopathological/personality dimensions were assessed through: Craving Typologies Questionnaire (CTQ); Obsessive-Compulsive Drinking Scale (OCDS); UPPS-P Impulsive Behavior Scale (S-UPPS-P); Difficulties in Emotion Regulation Scale (DERS). A binomial logistic regression explored factors associated with PSU.

RESULTS

We found higher CTQ 'reward' scores (p < 0.001) in AUD-PSU patients, and a significant association between reward craving and PSU through logistic regression (OR:1.13; p = 0.005). Earlier AUD onset (p < 0.001), greater rates of binge drinking (p = 0.029), more legal problems (p = 0.015), but no significantly higher S-UPPS-S and DERS scores, were detected in AUD-PSU patients.

CONCLUSIONS

Reward craving was associated with increased risk for PSU in severe AUD patients. Given AUD-PSU participants greater severity and detrimental treatment responses imputed to PSU, identifying prevalent craving types among risk factors for PSU in AUD may help to implement therapeutic strategies. Addressing neurobiological and behavioral mechanisms through combined psychotherapies, pharmacological and neuromodulation treatments could support tailored interventions with better long-term outcome.

Quantifying aberrant approach-avoidance conflict in psychopathology: A review of computational approaches

Making effective decisions during approach-avoidance conflict is critical in daily life. Aberrant decision-making during approach-avoidance conflict is evident in a range of psychological disorders, including anxiety, depression, trauma-related disorders, substance use disorders, and alcohol use disorders. To help clarify etiological pathways and reveal novel intervention targets, clinical research into decision-making is increasingly adopting a computational psychopathology approach. This approach uses mathematical models that can identify specific decision-making related processes that are altered in mental health disorders. In our review, we highlight foundational approach-avoidance conflict research, followed by more in-depth discussion of computational approaches that have been used to model behavior in these tasks. Specifically, we describe the computational models that have been applied to approach-avoidance conflict (e.g., drift-diffusion, active inference, and reinforcement learning models), and provide resources to guide clinical researchers who may be interested in applying computational modeling. Finally, we identify notable gaps in the current literature and potential future directions for computational approaches aimed at identifying mechanisms of approach-avoidance conflict in psychopathology.

Symptoms of Protracted Alcohol Withdrawal in Patients with Alcohol Use Disorder: A Comprehensive Systematic Review

BACKGROUND

Alcohol withdrawal syndrome (AWS) is characterized by different phases (acute, early and protracted). Protracted alcohol withdrawal (PAW) presents some symptoms, which may persist for several weeks, months or even years after drinking cessation.

METHODS

We conducted a systematic review of the literature in major scientific databases on selected AWS symptoms (craving, sleep disorders, and anhedonia) in patients with alcohol use disorder.

RESULTS

Of the 102 eligible publications (70 RCTs and 32 cohort studies), 88 provided data on craving, 21 on sleep disorders, and 1 on anhedonia. Overall, 37 studies assessed craving using the Obsessive Compulsive Drinking Scale (OCDS). Pooled OCDS decreased from 24.2 at baseline to 18.8 at 1 week, 10.3 at 1 month and 9.7 at 3 months. The corresponding estimates for treated individuals were 23.9, 18.8, 8.7, and 8.8, and for non-treated subjects, they were 25.3, 13.9, 13.2, and 11.4, respectively. In 4 studies assessing sleep disorders using the Epworth Sleeping Scale (ESS), the scale remained stable in time, i.e., 7.3 at baseline, 7.3 at 1 week, 7.2 at 1 month, and 7.1 at 3 months.

CONCLUSION

This study confirms the presence of PAW after the resolution of the acute phase of AWS. The pharmacological approach to managing PAW may ensure a more rapid reduction of symptoms in three weeks. We highlight the importance of studying PAW and the ability of pharmacological treatment to reduce its symptoms. This review protocol is registered in Prospero (registration number: CRD42020211265).

SUMMARY

This systematic review summarizes literature on major symptoms of protracted alcohol withdrawal in patients with alcohol use disorder. The pharmacological approach to manage protracted alcohol withdrawal ensures a more rapid reduction of symptoms (craving in particular), achieving in three weeks similar results obtained only after almost 6 months without treatment.

Translational models of addiction phenotypes to advance addiction pharmacotherapy

Alcohol and substance use disorders are heterogeneous conditions with limited effective treatment options. While there have been prior attempts to classify addiction subtypes, they have not been translated into clinical practice. In an effort to better understand heterogeneity in psychiatric disorders, the National Institute for Mental Health Research Domain Criteria (RDoC) has challenged scientists to think beyond diagnostic symptoms and to consider the underlying features of psychopathology from a neuroscience-based framework. The field of addiction has grappled with this approach by considering several key constructs with the potential to capture RDoC domains. This critical review will focus on the efforts to apply translational models of addiction phenomenology in human clinical samples, including their relative strengths and weaknesses. Opportunities for forward and reverse translation are also discussed. Deep behavioral phenotyping using neuroscience-informed batteries shows promise for a better understanding of the clinical neuroscience of addiction and advancing precision medicine for alcohol and substance use disorders.

Advances in neuroimaging studies of alcohol use disorder (AUD)

Alcohol use disorder (AUD) is a worldwide problem and the most common substance use disorder. Chronic alcohol consumption may have negative effects on the body, the mind, the family, and even society. With the progress of current neuroimaging methods, an increasing number of imaging techniques are being used to objectively detect brain impairment induced by alcoholism and serve a vital role in the diagnosis, prognosis, and treatment assessment of AUD. This article organizes and analyzes the research on alcohol dependence concerning the main noninvasive neuroimaging methods, structural magnetic resonance imaging, functional magnetic resonance imaging, and electroencephalography, as well as the most common noninvasive brain stimulation - transcranial magnetic stimulation, and intersperses the article with joint intra- and intergroup studies, providing an outlook on future research directions.

Pain Catastrophizing Is Associated With Increased Alcohol Cue-Elicited Neural Activity Among Individuals With Alcohol Use Disorder

AIMS

The current study examined the association between pain catastrophizing and alcohol cue-elicited brain activation in individuals with alcohol use disorder (AUD).

METHODS

Non-treatment seeking heavy drinkers with AUD (n = 45; 28 males) completed self-report measures of pain catastrophizing and alcohol use/problems as part of a clinical trial of the neuroimmune modulator ibudilast. Participants were randomized to either placebo (n = 25) or ibudilast (n = 20) and completed an functional magnetic resonance imaging (fMRI) scan to assess neural activation to alcohol cues 1 week into the medication trial. Multiple linear regression examined whether pain catastrophizing predicted cue-induced activation in a priori regions of interest, namely the dorsal and ventral striatum (VS). An exploratory whole-brain analysis was conducted to assess the relationship between pain catastrophizing and neural alcohol cue reactivity.

RESULTS

Pain catastrophizing predicted greater cue-induced activation in the dorsal (b = 0.006; P = 0.03) but not VS controlling for medication. Pain catastrophizing was positively associated with neural activation to alcohol cues in regions including the bilateral thalamus, left precuneus and left frontal pole.

CONCLUSION

Greater pain catastrophizing is associated with greater cue-induced neural activation in brain regions sub-serving habits and compulsive alcohol use. These findings provide initial support for a neural mechanism by which pain catastrophizing may drive alcohol craving among individuals with AUD.

Reciprocal midbrain-extended amygdala circuit activity in preclinical models of alcohol use and misuse

Alcohol dependence is characterized by a shift in motivation to consume alcohol from positive reinforcement (i.e., increased likelihood of future alcohol drinking based on its rewarding effects) to negative reinforcement (i.e., increased likelihood of future alcohol drinking based on alcohol-induced reductions in negative affective symptoms, including but not limited to those experienced during alcohol withdrawal). The neural adaptations that occur during this transition are not entirely understood. Mesolimbic reinforcement circuitry (i.e., ventral tegmental area [VTA] neurons) is activated during early stages of alcohol use, and may be involved in the recruitment of brain stress circuitry (i.e., extended amygdala) during the transition to alcohol dependence, after chronic periods of high-dose alcohol exposure. Here, we review the literature regarding the role of canonical brain reinforcement (VTA) and brain stress (extended amygdala) systems, and the connections between them, in acute, sub-chronic, and chronic alcohol response. Particular emphasis is placed on preclinical models of alcohol use.

Ibudilast attenuates alcohol cue-elicited frontostriatal functional connectivity in alcohol use disorder

BACKGROUND

Ibudilast, a novel neuroimmune modulator being studied to treat alcohol use disorder (AUD), was shown in a randomized controlled trial (NCT03489850) to reduce ventral striatum (VS) activation in response to visual alcohol cues. The present study extended this finding by probing the effects of ibudilast on alcohol cue-elicited functional connectivity (i.e., temporally correlated activation) with the VS seed. The study also tests the association between functional connectivity and alcohol use during the trial.

METHODS

Non-treatment-seeking participants (n = 45) with current alcohol use disorder were randomized to receive twice-daily dosing with either ibudilast (50 mg; n = 20) or placebo (n = 25). Upon reaching the target dosagee of the medication or placebo, participants completed a functional neuroimaging alcohol cue reactivity paradigm. Drinks per drinking day were assessed at baseline and daily during the 2-week trial.

RESULTS

Ibudilast reduced alcohol cue-elicited functional connectivity between the VS seed and reward-processing regions including the orbitofrontal and anterior cingulate cortices compared with placebo (p < 0.05). Cue-elicited functional connectivity was correlated with drinks per drinking day (R2  = 0.5351, p < 0.001), and ibudilast reduced this association in similar reward-processing regions compared with placebo.

CONCLUSIONS

Ibudilast's effects on drinking outcomes may be related to the attenuation of functional connectivity in frontostriatal circuits related to reward processing. These results provide an important proof of concept for this novel pharmacotherapy and support the clinical utility of incorporating neuroimaging-and especially functional connectivity-analyses into medication development.

Reinforcement-based cognitive biases as vulnerability factors in alcohol addiction: From humans to animal models

Alcohol use disorder (AUD) is one of the most common, but still poorly treated, psychiatric conditions. Developing new treatments requires a better understanding of the aetiology of symptoms and evaluation of novel therapeutic targets in preclinical studies. Recent developments in our understanding of the reinforcement-based cognitive biases (RBCBs) that contribute to the development of AUD and its treatment offer new opportunities for both clinical and preclinical research. In this review, we first briefly describe psychological and cognitive theories that involve various aspects of reinforcement sensitivity in the development, maintenance, and recurrence of alcohol addiction. Furthermore, in separate sections, we describe studies investigating RBCBs and their neural, neurochemical, and pharmacological correlates, and we discuss possible interactions between RBCBs and trajectories of AUD. Finally, we describe how recent translational studies using state-of-the-art animal models can facilitate our understanding of the role of reinforcement sensitivity and RBCBs in various aspects of AUD.