Neurocognitive deficits, craving, and abstinence among alcohol-dependent individuals following detoxification

Problematic alcohol use and its impact on liver disease quality of life in a multicenter study of patients with cirrhosis

BACKGROUND

Management of cirrhosis is challenging and has been complicated by the COVID-19 pandemic due to decreased access to care, increased psychological distress, and alcohol misuse. Recently, The National Institute on Alcohol Abuse and Alcoholism has broadened the definition of recovery from alcohol use disorder to include quality of life (QoL) as an indicator of recovery. This study examined the associations of alcohol-associated cirrhosis etiology and problematic drinking with liver disease QoL (LDQoL).

METHODS

Patients with cirrhosis (N=329) were recruited from 3 sites (63% from 2 Veterans Affairs Health Care Systems and 37% from 1 safety net hospital) serving populations that are economically or socially marginalized. Cirrhosis etiology was ascertained by chart review of medical records. Problematic drinking was defined by ≥8 on the Alcohol Use Disorders Identification Test. Multivariable general linear modeling adjusting for age, sex, race/ethnicity, site, pandemic-related stress, and history of anxiety/depressive disorder were conducted. Sensitivity analyses further adjusted for indicators of liver disease severity.

RESULTS

Participants were on average 64.6 years old, 17% female, 58% non-White, 44% with alcohol-associated cirrhosis, and 17% with problematic drinking. Problematic drinking was significantly associated with worse LDQoL scores in the overall scale and in the memory/concentration and health distress subscales. These associations remained significant after adjusting for indicators of liver disease severity, including Model for End-Stage Liver Disease-Sodium score and decompensated cirrhosis status.

CONCLUSIONS

Among patients with cirrhosis, problematic drinking was associated with worse LDQoL, especially in the domains of memory/concentration and health distress. Assessment and awareness of cognitive deficits and negative emotionality within the context of cirrhosis and problematic drinking may help clinicians provide better integrated care for this population.

A Study of the association of neurocognition with relapse and quality of life in patients of alcohol dependence

Background

Alcohol is a widely consumed substance associated with around 5.6% of all causes of death. Alcohol use disorder (AUD) is a chronic relapsing and remitting illness and has been known to be associated with impaired executive functions, processing speed, memory, attention, and fluency. It is also associated with impaired quality of life (QoL), which in turn can affect overall prognosis.

Aim

To assess neurocognition in patients with alcohol dependence and correlate it with QoL and relapse.

Materials and Methods

This study was a prospective, longitudinal study of sixty alcohol dependence patients from January 2020 to June 2021 after appropriate ethical approval. Participants were assessed for baseline alcohol dependence, neurocognition (focused, sustained and divided attention; processing speed; verbal and category fluency; working memory; response inhibition; verbal comprehension; verbal learning and memory; visuospatial construction; visual learning and memory) and QoL using Alcohol Use Disorders Identification Test (AUDIT), National Institute of Mental Health and Neurosciences (NIMHANS) battery for neurocognition and WHO-BREF (WHO-Quality of Life-short-form scale) World Health Organization-scale, respectively. A follow-up was conducted in three months to assess relapse in the patients. Statistical analysis was conducted by International Business Machines Statistical Package for the Social Sciences (IBM SPSS) v16.

Results

Mean age of the study participants was 41.3 ± 5.03 years, mean age of onset of alcohol use was 20.88 ± 4.27 years, mean duration of alcohol use of 16.6 ± 7.92 years, and average 14.55 ± 4.86 drinks per day. The mean AUDIT score of the study population was 25.21 ± 7.18. There was significant positive correlation between duration of use and CTT-2; 37 out of 57 participants relapsed to alcohol (three participants had died in follow-up) with mean 37.48 ± 23.27 days of relapse, mean 3.32 ± 1.2 drinking days per week, and mean 6 ± 1.2 drinks per drinking day. There was negative and positive correlation between neurocognition and relapse and between neurocognition and QoL.

Conclusion

Alcohol use also resulted in impaired cognitive function of the study participants. There was also significant difference in score for neurocognition test between relapse and abstinent group. The significant correlation between neurocognition and QoL as well as neurocognition and relapse proves the deleterious effect of alcohol in every aspect of life.

Blunted neural reward response to alcohol and greater alcohol motivation in binge drinkers in a randomized clinical experiment

BACKGROUND

Alcohol stimulates cerebral blood flow (CBF) in brain reward regions. However, neural processes that support sustained alcohol motivation after the first drink are not well understood.

METHODS

Using a novel placebo-controlled, randomized, crossover experiment, 27 individuals who binge drink (BD; 15 M, 12 F) and 25 social drinkers (SD; 15 M, 10 F) underwent a behavioral test of self-motivated alcohol consumption using an Alcohol Taste Test (ATT) involving alcoholic and nonalcoholic beer on separate days. The test was followed immediately by perfusion functional magnetic resonance imaging (fMRI). On both days, participants then engaged in a post-scan ATT with placebo beer to assess sustained alcohol self-motivation without active alcohol effects. Linear mixed effects models were used to examine the effects of drinking group on the placebo-controlled effect of initial alcohol motivation on brain perfusion (whole brain corrected p < 0.001, cluster corrected p < 0.025) and on the relationship between placebo-controlled brain perfusion and sustained alcohol motivation.

RESULTS

Initial alcohol self-motivation in the alcohol relative to placebo session led to markedly decreased activation in the medial orbitofrontal cortex (OFC) and the ventral striatum in BD relative to SD, indicative of neural reward tolerance. The BD group also showed an enhanced neural response in behavioral intention regions of the supplementary motor area (SMA) and inferior frontal gyrus (IFG) regions. Moreover, there was greater sustained alcohol motivation in BD than SD in the post-scan ATT in the alcohol relative to placebo session. Correspondingly, only in BD and only in the alcohol session, lower alcohol-induced OFC response correlated with concurrent sensitized SMA response, and each predicted the subsequent sustained higher alcohol motivation in the post-scan ATT.

CONCLUSIONS

Alcohol-related OFC tolerance may play an important role in sustained alcohol motivation. Furthermore, both specific alcohol-related neural reward tolerance and premotor sensitization responses may contribute to escalating alcohol motivation to drive excessive alcohol intake, even in individuals without alcohol use disorder.

Counting on random number generation: Uncovering mild executive dysfunction in congenital heart disease

Congenital heart disease (CHD) is associated with various neurocognitive deficits, particularly targeting executive functions (EFs), of which random number generation (RNG) is one indicator. RNG has, however, never been investigated in CHD. We administered the Mental Dice Task (MDT) to 67 young adults with CHD and 55 healthy controls. This 1-minute-task requires the generation of numbers 1 to 6 in a random sequence. RNG performance was correlated with a global EF score. Participants underwent MRI to examine structural-volumetric correlates of RNG. Compared to controls, CHD patients showed increased backward counting, reflecting deficient inhibition of automatized behavior. They also lacked a small-number bias (higher frequency of small relative to large numbers). RNG performance was associated with global EF scores in both groups. In CHD patients, MRI revealed an inverse association of counting bias with most of the volumetric measurements and the amount of small numbers was positively associated with corpus callosum volume, suggesting callosal involvement in the "pseudoneglect in number space". In conclusion, we found an impaired RNG performance in CHD patients, which is associated with brain volumetric measures. RNG, reportedly resistant to learning effects, may be an ideal task for the longitudinal assessment of EFs in patients with CHD.

The relationship between executive functioning and addictive behavior: new insights from a longitudinal community study

RATIONALE

Although there is evidence that impaired executive functioning plays a role in addictive behavior, the longitudinal relationship between the two remains relatively unknown.

OBJECTIVES

In a prospective-longitudinal community study, we tested the hypothesis that lower executive functioning is associated with more addictive behavior at one point in time and over time.

METHODS

Three hundred and thirty-eight individuals (19-27 years, 59% female) from a random community sample were recruited into three groups: addictive disorders related to substances (n = 100) or to behaviors (n = 118), or healthy controls (n = 120). At baseline, participants completed nine executive function tasks from which a latent variable of general executive functioning (GEF) was derived. Addictive behavior (i.e., quantity and frequency of use, and number of DSM-5 criteria met) were assessed using standardized clinical interviews at baseline and three annual follow-ups. The trajectories of addictive behaviors were examined using latent growth curve modeling.

RESULTS

At baseline, we found weak to no evidence of an associations between GEF and addictive behavior. We found evidence for an association between a lower GEF at baseline and a higher increase in the quantity of use and a smaller decrease in frequency of use over time, but no evidence for an association with an increase in the number of DSM-5 criteria met.

CONCLUSIONS

Lower EFs appear to lead to a continuing loss of control over use, whereas addictive disorders may develop secondarily after a long period of risky use. Previous etiological models assuming lower EF as a direct vulnerability factor for addictive disorders need to be refined.

Dutch forensic patients with and without intellectual disabilities: A comparison of demographic, offence, and diagnostic characteristics

BACKGROUND

Patients with an intellectual disability (ID) and offending histories constitute a challenging clinical group. The present study examined commonalities and differences in demographic, diagnostic and offence characteristics in patients with and without intellectual disabilities who were either convicted for violent or sexual offences and who resided in mandated care in the Netherlands.

METHOD

We compared 165 offenders with an ID to 249 offenders without an ID. We compared both groups by type of offence (i.e., sexual versus violent offence) using Mann-Whitney U-test or independent samples t-tests for continuous variables and Chi-square tests for categorical variables.

RESULTS

In general, forensic patients with an ID were younger at admission (U=357, z = -12.668, p < .001), had more prior convictions for violent offences (χ²(1)= 6.175, p = .013) and more prevalent diagnoses of substance abuse disorders (χ²(1)= 9.266, p = .002) than those without an ID. Similar results were found for patients with IDs with sexual offence histories.

CONCLUSION

A clear understanding of distinct characteristics of forensic patients with intellectual disabilities is crucial in understanding (sexual) violent behavior in this population as it mayassistclinicians in prioritizing interventionstrategies.

Anomalies in global network connectivity associated with early recovery from alcohol dependence: A network transcranial magnetic stimulation and electroencephalography study

Although previous research in alcohol dependent populations identified alterations within local structures of the addiction ‘reward’ circuitry, there is limited research into global features of this network, especially in early recovery. Transcranial magnetic stimulation (TMS) is capable of non‐invasively perturbing the brain network while electroencephalography (EEG) measures the network response. The current study is the first to apply a TMS inhibitory paradigm while utilising network science (graph theory) to quantify network anomalies associated with alcohol dependence. Eleven individuals with alcohol‐dependence (ALD) in early recovery and 16 healthy controls (HC) were administered 75 single pulses and 75 paired‐pulses (inhibitory paradigm) to both the left and right prefrontal cortex (PFC). For each participant, Pearson cross‐correlation was applied to the EEG data and correlation matrices constructed. Global network measures (mean degree, clustering coefficient, local efficiency and global efficiency) were extracted for comparison between groups. Following administration of the inhibitory paired‐pulse TMS to the left PFC, the ALD group exhibited altered mean degree, clustering coefficient, local efficiency and global efficiency compared to HC. Decreases in local efficiency increased the prediction of being in the ALD group, while all network metrics (following paired‐pulse left TMS) were able to adequately discriminate between the groups. In the ALD group, reduced mean degree and global clustering was associated with increased severity of past alcohol use. Our study provides preliminary evidence of altered network topology in patients with alcohol dependence in early recovery. Network anomalies were predictive of high alcohol use and correlated with clinical features of alcohol dependence. Further research using this novel brain mapping technique may identify useful network biomarkers of alcohol dependence and recovery.

Augmented tendency to act and altered impulse control in alcohol use disorders

Action preparation relies on the operation of control processes that modulate the excitability of the corticospinal tract. On the one hand, excitatory processes prepare the motor system for the forthcoming response; the stronger these influences, the stronger the tendency to act. On the other hand, inhibitory influences allow to suppress inappropriate actions and, more generally, to ensure some sort of impulse control. Because an impairment in these processes could foster inappropriate drinking behavior, the present study aimed at evaluating the motor correlates of such excitatory and inhibitory influences in non-treatment seeking heavy drinkers (HDs) and inpatients suffering from severe alcohol use disorder (SAUDs). Besides, as cue-elicited craving might further alter these processes, we also assessed the impact of an alcohol-related exposure. To do so, 15 healthy controls (HCs), 15 HDs and 15 SAUDs performed a choice reaction time task after having been immersed in a neutral or an alcohol-related environment, using virtual reality videos. Importantly, single-pulse transcranial magnetic stimulation was applied over the left and the right primary motor cortex during the task to elicit motor-evoked potentials in a set of hand muscles allowing us to specifically probe the impact of excitatory and inhibitory processes on motor activity. Our data indicate that excitatory influences are particularly high in both HDs and SAUDs, especially in the dominant hand, an effect that was not observed in HCs. By contrast, inhibitory influences were found to be perfectly normal in HDs, while they were lacking in SAUDs. Furthermore, the alcohol-related exposure enhanced the level of self-reported craving, but this effect only arose in HDs and did not significantly alter the strength of excitatory and inhibitory influences. Overall, although these results have to be taken with caution due to the small sample sizes, this study suggests that enhanced excitatory processes characterize both HDs and SAUDs, while weaker inhibitory influences only concern SAUDs. Hence, an abnormally strong tendency to act could represent a common feature of hazardous drinking, leading individuals to excessive alcohol consumption, whereas deficient impulse control would be a hallmark of more severe forms of AUD, potentially due to the chronic neurotoxic effects of alcohol. Finally, although an alcohol-related exposure does not seem to affect excitatory and inhibitory processes at play during action preparation per se, future works should evaluate changes in corticospinal excitability during the preparation of responses specifically targeting alcohol-related cues.

Binge drinking is associated with altered resting state functional connectivity of reward-salience and top down control networks

Binge drinking is characterized by bouts of high-intensity alcohol intake and is associated with an array of health-related harms. Even though the transition from occasional impulsive to addictive alcohol use is not well understood, neurobiological models of addiction suggest that repeated cycles of intoxication and withdrawal contribute to the development of addiction in part through dysregulation of neurofunctional networks. Research on the neural sequelae associated with binge drinking is scant but resting state functional connectivity (RSFC) studies of alcohol use disorders (AUD) indicate that the development and maintenance of long-term excessive drinking may be mediated by network-level disruptions. The present study examined RSFC in young adult binge (BD) and light (LD) drinkers with seeds representing the networks subserving reward (the nucleus accumbens and caudate nucleus), salience (anterior cingulate cortex, ACC), and executive control (inferior frontal cortex, IFC). BDs exhibited enhanced connectivity between the striatal reward areas and the orbitofrontal cortex and the ACC, which is consistent with AUD studies and may be indicative of alcohol-motivated appetitive behaviors. Conversely, BDs demonstrated lower connectivity between the IFC and hippocampus which was associated with higher craving. This may indicate impaired ability to suppress unwanted thoughts and a failure to employ memory of the harmful consequences of heavy drinking in prospective plans and intentions. The observed greater connectivity of the reward/salience network and the lower prefrontal-hippocampal connectivity were associated with hazardous drinking levels indicating that dysregulation of neurofunctional networks may underlie binge drinking patterns.

Evaluation of the retinal nerve fiber layer with optic coherence tomography in patients with alcohol use disorder

OBJECTIVE

This study aims to evaluate the retinal nerve fiber layer (RNFL) with optical coherence tomography (OCT) among patients with alcohol and tobacco use disorder.

METHODS

This study included 29 patients and 29 age and gender-matched healthy participants without alcohol dependency. The patients underwent full ophthalmologic examination including visual acuity, intraocular pressure, anterior segment and fundus examinations, and RNFL measurements taken with spectral-domain OCT. The RNFL values of the two groups were compared with each other.

RESULTS

In comparison to the control group, the RNFL was found to be thinner in all quadrants in the group with alcohol and tobacco dependency. The RNFL thinning in the superotemporal, temporal, and inferotemporal quadrants was found to be statistically significant (P-values 0.012, 0.040 and 0.005, respectively).

CONCLUSIONS

Chronic alcohol and tobacco use may cause RNFL thinning. Assessment of RNFL thinning by OCT among patients with alcohol and tobacco dependency might be used to identify visual morbidity.

Drawing alcohol craving process: A systematic review of its association with thought suppression, inhibition and impulsivity

Alcohol Use Disorder (AUD) is a worldwide public health problem. In recent years, there has been growing evidence supporting craving, the irrepressible desire to drink, as a major mechanism implicated in AUD. Impulsivity is identified as playing a significant role in craving in many studies. However, relationships with inhibition and thought suppression remain unclear in the existing literature. A systematic review was conducted to evaluate their associations in order to better understand the cognitive processes involved in craving.

Studies were identified by searching PubMed, PsycINFO and Web of Science using PRISMA procedure and PICOTS framework. There were included if they assessed craving and thought suppression or inhibition or impulsivity, and sample was composed of AUD participants.

Thirteen studies were included and were categorized in accordance with the evaluated cognitive process. The first part dealt with thought suppression and the second with impulsivity and inhibition. Four studies showed a positive association between thought suppression and increased craving. Two studies showed that poorer inhibition was associated with increased craving and four studies showed that impulsivity was positively associated with craving. Three studies showed a negative association between impulsivity and inhibition and higher craving.

Our review highlights the association of alcohol craving with poorer inhibition and greater impulsivity. Further investigations are needed to give support to different theories and lead to propose an integrative model involving the cognitive process of inhibition in alcohol craving.

Impulsive decision-making predicts the course of substance-related and addictive disorders

BACKGROUND

This study investigated whether patterns of impulsive decision-making (i) differ between individuals with DSM-5 substance use disorders (SUD) or non-substance-related addictive disorders (ND) and healthy controls, and (ii) predict the increase of SUD and ND severity after one year.

METHODS

In a prospective-longitudinal community study, 338 individuals (19-27 years, 59% female) were included in one of three groups: SUD (n = 100), ND (n = 118), or healthy controls (n = 120). Group differences in four impulsive decision-making facets were analyzed with the Bayesian priors: delay discounting (mean = 0.37, variance = 0.02), probability discounting for gains and for losses (each - 0.16, 0.02), and loss aversion (- 0.44, 0.02). SUD and ND severity were assessed at baseline and after 1 year (n = 312, 92%). Predictive associations between decision-making and SUD/ND severity changes were analyzed with the Bayesian prior: mean = 0.25, variance = 0.016.

RESULTS

Compared with controls, the SUD group displayed steeper delay discounting and lower probability discounting for losses; the ND group displayed lower probability discounting for losses (posterior probabilities > 98%). SUD symptom increase after 1 year was predicted by steeper delay discounting and lower loss aversion; ND symptom increase by lower probability discounting for losses and lower loss aversion (posterior probabilities > 98%). There was low evidence for predictive relations between decision-making and the quantity-frequency of addictive behaviours.

DISCUSSION

Impulsive decision-making characterizes SUD and ND and predicts the course of SUD and ND symptoms but not the engagement in addictive behaviours. Strength of evidence differed between different facets of impulsive decision-making and was mostly weaker than a priori expected.

Intranasal Insulin: a Treatment Strategy for Addiction

Addiction to substances such as alcohol, cocaine, opioids, and methamphetamine poses a continuing clinical and public challenge globally. Despite progress in understanding substance use disorders, challenges remain in their treatment. Some of these challenges include limited ability of therapeutics to reach the brain (blood-brain barrier), adverse systemic side effects of current medications, and importantly key aspects of addiction not addressed by currently available treatments (such as cognitive impairment). Inability to sustain abstinence or seek treatment due to cognitive deficits such as poor decision-making and impulsivity is known to cause poor treatment outcomes. In this review, we provide an evidenced-based rationale for intranasal drug delivery as a viable and safe treatment modality to bypass the blood-brain barrier and target insulin to the brain to improve the treatment of addiction. Intranasal insulin with improvement of brain cell energy and glucose metabolism, stress hormone reduction, and improved monoamine transmission may be an ideal approach for treating multiple domains of addiction including memory and impulsivity. This may provide additional benefits to enhance current treatment approaches.

The Evaluation of Cognitive Impairment in Alcohol-Dependent Patients Through RBANS Combined With ERPs

Background: Recently, the cognitive impairment of patients with alcohol dependence has attracted more and more attention. The combination of Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and event-related potentials (ERPs) for evaluating the degree of cognitive impairment in patients with alcohol dependence has not undergone enough in-depth investigation. Method: Sixty patients with alcohol dependence were selected as alcohol-dependence group, whereas 40 healthy volunteers served as a normal control group. The original scores of the RBANS sub-items, the incubation period, and volatility of ERPs between the two groups were compared, and the correlation among the above indicators in the alcohol-dependence group was further analyzed. Results: The RBANS test showed that the original scores of speech function, attention function, delayed memory, and immediate attention in the alcohol-dependence group were significantly lower than those in the normal control group. Compared with the normal control group, the latencies of P200 and P300 in the alcohol-dependence group were significantly prolonged, and the amplitude of P200 and P300 was significantly reduced. Correlation analysis between RBANS and ERPs in alcohol-dependence group showed that immediate attention score was positively correlated with P300 and P200 amplitude, visual breadth score was positively correlated with P200 latency, and attention function score was negatively correlated with P300 latency. Conclusion: As RBANS scale was highly correlated with the results of ERPs, the combined use of these two scales may serve as an objective basis for early diagnosis of cognitive impairment in patients with alcohol dependence.

Brain-behavior relations and effects of aging and common comorbidities in alcohol use disorder: A review

OBJECTIVE

Alcohol use disorder (AUD) is a complex, dynamic condition that waxes and wanes with unhealthy drinking episodes and varies in drinking patterns and effects on brain structure and function with age. Its excessive use renders chronically heavy drinkers vulnerable to direct alcohol toxicity and a variety of comorbidities attributable to nonalcohol drug misuse, viral infections, and accelerated or premature aging. AUD affects widespread brain systems, commonly, frontolimbic, frontostriatal, and frontocerebellar networks.

METHOD AND RESULTS

Multimodal assessment using selective neuropsychological testing and whole-brain neuroimaging provides evidence for AUD-related specific brain structure-function relations established with double dissociations. Longitudinal study using noninvasive imaging provides evidence for brain structural and functional improvement with sustained sobriety and further decline with relapse. Functional imaging suggests the possibility that some alcoholics in recovery can compensate for impairment by invoking brain systems typically not used for a target task but that can enable normal-level performance.

CONCLUSIONS

Evidence for AUD-aging interactions, indicative of accelerated aging, together with increasing alcohol consumption in middle-age and older adults, put aging drinkers at special risk for developing cognitive decline and possibly dementia. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Naltrexone differentially modulates the neural correlates of motor impulse control in abstinent alcohol-dependent and polysubstance-dependent individuals

Identifying key neural substrates in addiction disorders for targeted drug development remains a major challenge for clinical neuroscience. One emerging target is the opioid system, where substance-dependent populations demonstrate prefrontal opioid dysregulation that predicts impulsivity and relapse. This may suggest that disturbances to the prefrontal opioid system could confer a risk for relapse in addiction due to weakened 'top-down' control over impulsive behaviour. Naltrexone is currently licensed for alcohol dependence and is also used clinically for impulse control disorders. Using a go/no-go (GNG) task, we examined the effects of acute naltrexone on the neural correlates of successful motor impulse control in abstinent alcoholics (AUD), abstinent polysubstance-dependent (poly-SUD) individuals and controls during a randomised double blind placebo controlled fMRI study. In the absence of any differences on GNG task performance, the AUD group showed a significantly greater BOLD response compared to the control group in lateral and medial prefrontal regions during both placebo and naltrexone treatments; effects that were positively correlated with alcohol abstinence. There was also a dissociation in the positive modulating effects of naltrexone in the orbitofrontal cortex (OFC) and anterior insula cortex (AIC) of the AUD and poly-SUD groups respectively. Self-reported trait impulsivity in the poly-SUD group also predicted the effect of naltrexone in the AIC. These results suggest that acute naltrexone differentially amplifies neural responses within two distinct regions of a salience network during successful motor impulse control in abstinent AUD and poly-SUD groups, which are predicted by trait impulsivity in the poly-SUD group.

Behavioral and Cerebral Impairments Associated with Binge Drinking in Youth: A Critical Review

Binge drinking is a widespread alcohol consumption pattern in youth that is linked to important behavioral and cerebral impairments, in both the short and the long term. From a critical review of the current literature on this topic, we conclude that binge drinkers display executive impairments, cerebral modifications, and problems with emotion-related processes. Five key empirical and theoretical topics are discussed to pave the way for future research in the field: (1) the specificity of the brain modifications observed in binge drinkers that may index a compensatory mechanism or result from multiple withdrawals; (2) the nature of the relationship between binge drinking and impairments, suggesting reciprocal influences between excessive alcohol consumption and executive deficits; (3) the possible recovery of brain and cognitive functioning after the cessation of binge drinking; (4) the validity of the continuum hypothesis, suggesting links between binge drinking and severe alcohol use disorders; and (5) the existing strategies to reduce binge drinking habits or rehabilitate the associated cognitive deficits. Future perspectives are described in relation to the questions raised to identify the crucial variables to be addressed in research and clinical practice.

Neurocognitive Precursors of Substance Misuse Corresponding to Risk, Resistance, and Resilience Pathways: Implications for Prevention Science

Studies of substance misuse prevention generally focus on characteristics that typify risk, with the assumption that the prevalence of the problem will be optimally reduced by identifying, targeting, and reducing or eliminating risk factors. However, this risk-centered approach neglects variations in individual-level and environmental characteristics that portend differential pathways that are distinguishable by timing of substance use initiation (e.g., early versus delayed), the likelihood of use escalation versus eventual desistance, and enduring abstinence, despite exposure to significant risk factors. Considering the various underpinnings of these distinct substance use trajectories is critical to a more nuanced understanding of the effects, potency, and malleability of factors that are known to increase risk or confer protection. Here, we discuss three pathways relative to substance use patterns and predictors in the context of adversity, a well-known, highly significant influence on propensity for substance misuse. The first pathway is designated as "high risk" based on early onset of substance use, rapid escalation, and proneness to substance use disorders. Individuals who defy all odds and eventually exhibit adaptive developmental outcomes despite an initial maladaptive reaction to adversity, are referred to as "resilient." However, another categorization that has not been adequately characterized is "resistant." Resistant individuals include those who do not exhibit problematic substance use behaviors (e.g., early onset and escalation) and do not develop substance use disorders or other forms of psychopathology, despite significant exposure to factors that normally increase the propensity for such outcomes (e.g. trauma and/or adversity). In this paper, we apply this conceptualization of risk, resistance, and resilience for substance misuse to a more fine-grained analysis of substance use pathways and their corresponding patterns (e.g., non-use, initiation, escalation, desistance). The significance of the progression of neurocognitive functioning over the course of development is discussed as well as how this knowledge may be translated to make a science-based determination of intervention targets. This more encompassing theoretical model has direct implications for primary prevention and clinical approaches to disrupt risk pathways and to optimize long-term outcomes.

Impulsivity, Sensation Seeking, and Decision-Making in Long-Term Abstinent Cannabis Dependent Patients

Introduction

In contrast to several studies that examined different domains of neurocognitive functions in long-term abstinent cannabis users, there are few studies examined impulsivity in cannabis users with prolonged abstinence. The aim of this study was to test whether impulsivity and sensation seeking traits and impulsive decision-making are transient or enduring in patients with cannabis dependence who were abstinent for at least 1 month.

Methods

The study included 30 patients with cannabis dependence (CDP) who had been abstinent for at least 1 month and 30 healthy controls. All the participants were male and the two groups were matched for age and duration of education.

Results

As a result of Iowa Gambling Task (IGT) evaluation, there was no significant group (CDP vs. control) by block interaction in IGT performance (p=0.680). CDP showed significantly higher Barratt Impulsiveness Scale-11 (BIS-11) total (p=0.006), BIS-11 non-planning (p=0.006) and Zuckerman Sensation Seeking Scale experience seeking subscale (p=0.001) scores compared with controls.

Conclusions

This is the first study to investigate decision-making, self-report impulsivity and sensation seeking in long-term abstinent CDP. Our findings suggest that both self-report impulsivity and experience seeking may reflect a stable trait in CDP but not deficits on decision-making. This suggestion is consistent with the hypothesis that elevated impulsivity and sensation seeking traits may lead to addiction when they occur together rather than alone.

ADX-47273, a mGlu5 receptor positive allosteric modulator, attenuates deficits in cognitive flexibility induced by withdrawal from 'binge-like' ethanol exposure in rats

Repeated exposure to and withdrawal from ethanol induces deficits in spatial reversal learning. Data indicate that metabotropic glutamate 5 (mGlu5) receptors are implicated in synaptic plasticity and learning and memory. These receptors functionally interact with N-methyl-d-aspartate (NMDA) receptors, and activation of one type results in the activation of the other. We examined whether (S)-(4-fluorophenyl)(3-(3-(4-fluorophenyl)-1,2,4-oxadiazol-5-yl)-piperidin-1-yl (ADX-47273), a positive allosteric modulator (PAM) of mGlu5 receptor, attenuates deficits in reversal learning induced by withdrawal (11-13days) from 'binge-like' ethanol input (5.0g/kg, i.g. for 5days) in the Barnes maze (a spatial learning) task in rats. We additionally examined the effects of ADX-47273 on the expression of the NMDA receptors subunit, GluN2B, in the hippocampus and prefrontal cortex, on the 13th day of ethanol withdrawal. Herein, withdrawal from repeated ethanol administration impaired reversal learning, but not the probe trial. Moreover, ADX-47273 (30mg/kg, i.p.) given prior to the first reversal learning trial for 3days in the Barnes maze, significantly enhanced performance in the ethanol-treated group. The 13th day of ethanol abstinence decreased the expression of the GluN2B subunit in the selected brain regions, but ADX-47273 administration increased it. In conclusion, positive allosteric modulation of mGlu5 receptors recovered spatial reversal learning impairment induced by withdrawal from 'binge-like' ethanol exposure. Such effect seems to be correlated with the mGlu5 receptors mediated potentiation of GluN2B-NMDA receptor mediated responses in the hippocampus and prefrontal cortex. Thus, our results emphasize the role of mGlu5 receptor PAM in the adaptive learning impaired by ethanol exposure.

Seasonal affective disorder and alcohol abuse disorder in a population-based study

Seasonal affective disorder (SAD) is a recurrent major depressive disorder with a seasonal pattern, which is characterized by sad mood, low energy, longer sleep duration and carbohydrate craving. Furthermore, seasonal changes in mood and behavior may be closely related to alcohol use disorder (AUD). Nevertheless, there is scarce research on the study of cognitive impairments in SAD and AUD. We aimed to examine the relationship between the prevalence between SAD and AUD patients, and how cognitive functioning might be related to these variables. To do this, a sample of 8135 Finnish subjects was invited to take part in the population-based Health 2011 Survey, of whom 5903 did participate and 4554 were interviewed for mental health status with the Munich version of Composite International Diagnostic Interview. They also completed the modified Seasonal Pattern Assessment Questionnaire, the Mini-Mental State Examination, the category (animals) verbal fluency test, and the Rey Auditory Verbal Learning Test. Our results reveal the existence of a strong link between SAD and AUD in a large sample of Finnish population, as well as association between SAD and short-term memory problems.

Cognitive changes in alcohol-induced psychotic disorder

AIMS

This study aimed to explore the neuro-cognitive deficits of alcohol-induced psychotic disorder as compared to the cognitive deficits of uncomplicated alcohol dependence.

METHODS

Participants were recruited from the acute psychiatric admission wards of the Department of Psychiatry, University of Stellenbosch and Stikland and Tygerberg Academic Hospitals in the Western-Cape, South Africa. Participants who met DSM IV TR criteria (American Psychiatric Association. Diagnostic and statistical manual of mental disorders. American Psychiatric Association, Washington, DC, 2000) for Alcohol Dependence and for alcohol-induced psychotic disorder, respectively, were included. Participants who met criteria for another current DSM IV TR Axis I disorder were excluded. A structured interview was done prior to neuropsychological assessment to ascertain current mental state and to obtain relevant demographic detail and history. Neuropsychological assessments were performed and supervised by clinical psychologists at either Tygerberg or Stikland Hospital.

RESULTS

The groups were matched demographically with similar period of abstinence prior to assessment. The alcohol-induced psychotic disorder group experienced first psychotic symptoms at age 35. The results reflected statistically significant differences on tasks measuring immediate memory; recall upon delay; exaggeration of memory difficulty and abstract thinking.

CONCLUSION

This study concurs with earlier literature that some cognitive deficits are greater in alcohol-induced psychotic disorder compared to uncomplicated alcohol dependence.

Do alcohol-dependent patients show different neural activation during response inhibition than healthy controls in an alcohol-related fMRI go/no-go-task?

RATIONALE

Alcohol dependence is associated with impaired response inhibition and heightened cue reactivity towards alcohol-related stimuli. Several brain areas, but mainly prefrontal structures, have been linked to response inhibition in addiction. This study aimed at combining both aspects: salience of drug-associated cues and response inhibition using a go/no-go task with alcohol-associated stimuli during functional magnetic resonance imaging (fMRI).

OBJECTIVES

Nineteen abstinent alcohol-dependent patients (ADP) and 21 healthy control subjects (HC) were compared on blood oxygen level-dependent (BOLD) responses during successful inhibition of no-go stimuli and successful reactions to go stimuli.

RESULTS

ADP and HC did not significantly differ in their behavioural performance in the task. However, both groups performed worse during the inhibition of alcoholic-associated stimuli compared to neutral stimuli. On the neural level, ADP displayed enhanced BOLD activity relative to HC during successful response inhibition in several areas involved in visual processing, cognitive and impulse control, including occipital structures, anterior cingulate gyrus, medial frontal gyrus and medial orbitofrontal cortex.

CONCLUSIONS

We interpret these findings as a possible compensation strategy for impaired cognitive processing. Furthermore, the results underline the impact of salience of alcohol-related stimuli on response inhibition, which seems to affect both ADP and HC.

Neurocognition and inhibitory control in polysubstance use disorders: Comparison with alcohol use disorders and changes with abstinence

INTRODUCTION

Intact neurocognition and early cognitive recovery during abstinence are important for substance use treatment outcome. Yet, little is known about them in the largest group of treatment seekers today, individuals with polysubstance use disorders (PSU). This study primarily contrasted PSU and individuals with an alcohol use disorder (AUD) on neurocognitive and inhibitory control measures and, secondarily, measured changes during abstinence in PSU.

METHOD

At one month of abstinence from all substances except tobacco, 36 PSU and 69 AUD completed neurocognitive assessments of executive function, general intelligence, auditory-verbal learning/memory, visuospatial learning/memory/skills, processing speed, working memory, fine motor skills, and cognitive efficiency. The groups were also assessed on inhibitory control measures of self-reported impulsivity, risk-taking, and decision-making. Seventeen PSU repeated the assessments after approximately four months of abstinence. All cross-sectional and longitudinal analyses included smoking status as a possible confound.

RESULTS

At baseline, PSU performed significantly worse than AUD on auditory-verbal memory and on an inhibitory control measure of impulsivity. Polysubstance users showed trends to worse performance than AUD on general intelligence, auditory-verbal learning, and a decision-making task. Between one and four months of abstinence, PSU showed significant improvements on several neurocognitive and inhibitory control measures.

CONCLUSIONS

Polysubstance users exhibit distinct differences in neurocognition and inhibitory control compared to AUD. Between one and four months of abstinence, neurocognition and inhibitory control improve in PSU. This neurocognitive recovery in some domains of abstinent PSU is influenced by smoking status. These results underscore the clinical value of select methods to augment neurocognitive recovery in PSU through appropriate interventions.

Reversal learning and experimenter-administered chronic intermittent ethanol exposure in male rats

RATIONALE

Chronic alcohol exposure is associated with impaired decision making skills, cognitive deficits, and poor performance on tasks requiring behavioral flexibility. Although oral routes of alcohol administration are commonly used to examine effects of alcohol on various behaviors in rodents, only a few investigations have used intragastric exposures to evaluate ethanol's effects on behavioral flexibility in the adult rat.

OBJECTIVES

The aim of the current series of experiments was to determine if behavioral flexibility impairments would be demonstrated across a variety of procedural factors, including route of administration [intraperitoneal injection (i.p.), intragastric gavage (i.g.)], ethanol dose (3-5 g/kg), number of daily exposures (once/day, twice/day), duration of exposure (2-6 weeks), or length of abstinence (5-7 days).

METHODS

Adult male Sprague-Dawley rats were exposed to chronic intermittent ethanol (CIE) or vehicle and evaluated for behavioral intoxication, blood ethanol concentrations (BEC), and performance on a reversal learning odor discrimination task.

RESULTS

While all rats displayed behavioral intoxication and elevated BECs, CIE i.p. rats had prolonged elevation in BECs and made the most errors during the reversal learning task. Unexpectedly, CIE i.g. exposures failed to produce deficits during reversal learning tasks regardless of ethanol dose, frequency/duration of exposure, or length of abstinence.

CONCLUSIONS

Behavioral flexibility deficits resulting from CIE i.p. exposures may be due to the severity and chronicity of alcohol intoxication. Elucidating the impact of ethanol on behavioral flexibility is critical for developing a better understanding of the behavioral consequences of chronic alcohol exposure.

The impact of cognitive impairment and impulsivity on relapse of alcohol-dependent patients: implications for psychotherapeutic treatment

Recent models of the development of addiction propose a transition from a pleasure-driven to a heavily automatized behaviour, marked by a loss of cognitive control. This study investigated the deficits in different components of cognitive functions including behavioural inhibition in response to alcohol-related stimuli in alcohol-dependent patients (ADP) and healthy controls (HC). The aims of the study were to identify which particular cognitive functions are impaired in ADP. Furthermore, we analysed the association between cognitive deficits and relapse rates and the reversibility of cognitive deficits under abstinence in a 6-month follow-up period. Ninety-four recently detoxified ADP and 71 HC completed the cognitive tasks as well as questionnaire measures assessing drinking behaviour and personality traits. Compared with HC, ADP showed poorer performance in response initiation, response inhibition, complex-sustained attention and executive functions. Impairment in response inhibition was a significant predictor for relapse, yet the strongest predictor was the interaction between the number of previous detoxifications and response-inhibition deficits. The results of a moderation analysis showed that patients with many previous detoxifications and large deficits in response inhibition showed the highest relapse risk. These findings indicate that interventions should take into account inhibitory deficits especially in ADP with a high number of previous detoxifications.

Association Splitting: A randomized controlled trial of a new method to reduce craving among inpatients with alcohol dependence

Association Splitting, a novel cognitive intervention, was tested in patients with alcohol dependence as an add-on intervention in an initial randomized controlled trial. Preliminary support for Association Splitting has been found in patients with obsessive-compulsive disorder, as well as in an online pilot study of patients with alcohol use disorders. The present variant sought to reduce craving by strengthening neutral associations with alcohol-related stimuli, thus, altering cognitive networks. Eighty-four inpatients with verified diagnoses of alcohol dependence, who were currently undergoing inpatient treatment, were randomly assigned to Association Splitting or Exercise Therapy. Craving was measured at baseline, 4-week follow-up, and six months later with the Obsessive-Compulsive Drinking Scale (primary outcome) and the Alcohol Craving Questionnaire. There was no advantage for Association Splitting after three treatment sessions relative to Exercise Therapy. Among Association Splitting participants, 51.9% endorsed a subjective decline in craving and 88.9% indicated that they would use Association Splitting in the future. Despite high acceptance, an additional benefit of Association Splitting beyond standard inpatient treatment was not found. Given that participants were concurrently undergoing inpatient treatment and Association Splitting has previously shown moderate effects, modification of the study design may improve the potential to detect significant effects in future trials.

Impulsivity in abstinent alcohol and polydrug dependence: a multidimensional approach

RATIONALE

Dependence on drugs and alcohol is associated with impaired impulse control, but deficits are rarely compared across individuals dependent on different substances using several measures within a single study.

OBJECTIVES

We investigated impulsivity in abstinent substance-dependent individuals (AbD) using three complementary techniques: self-report, neuropsychological and neuroimaging. We hypothesised that AbDs would show increased impulsivity across modalities, and that this would depend on length of abstinence.

METHODS

Data were collected from the ICCAM study: 57 control and 86 AbDs, comprising a group with a history of dependence on alcohol only (n = 27) and a group with history of dependence on multiple substances ("polydrug", n = 59). All participants completed self-report measures of impulsivity: Barratt Impulsiveness Scale, UPPS Impulsive Behaviour Scale, Behaviour Inhibition/Activation System and Obsessive-Compulsive Inventory. They also performed three behavioural tasks: Stop Signal, Intra-Extra Dimensional Set-Shift and Kirby Delay Discounting; and completed a Go/NoGo task during fMRI.

RESULTS

AbDs scored significantly higher than controls on self-report measures, but alcohol and polydrug dependent groups did not differ significantly from each other. Polydrug participants had significantly higher discounting scores than both controls and alcohol participants. There were no group differences on the other behavioural measures or on the fMRI measure.

CONCLUSIONS

The results suggest that the current set of self-report measures of impulsivity is more sensitive in abstinent individuals than the behavioural or fMRI measures of neuronal activity. This highlights the importance of developing behavioural measures to assess different, more relevant, aspects of impulsivity alongside corresponding cognitive challenges for fMRI.