Executive Functions, Memory, and Social Cognitive Deficits and Recovery in Chronic Alcoholism: A Critical Review to Inform Future Research

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.

Chronic intermittent ethanol promotes ventral subiculum hyperexcitability via increases in extrinsic basolateral amygdala input and local network activity

The hippocampus, particularly its ventral domain, can promote negative affective states (i.e. stress and anxiety) that play an integral role in the development and persistence of alcohol use disorder (AUD). The ventral hippocampus (vHC) receives strong excitatory input from the basolateral amygdala (BLA) and the BLA-vHC projection bidirectionally modulates anxiety-like behaviors. However, no studies have examined the effects of chronic alcohol on the BLA-vHC circuit. In the present study, we used ex vivo electrophysiology in conjunction with optogenetic approaches to examine the effects of chronic intermittent ethanol exposure (CIE), a well-established rodent model of AUD, on the BLA-vHC projection and putative intrinsic vHC synaptic plasticity. We discovered prominent BLA innervation in the subicular region of the vHC (vSub). CIE led to an overall increase in the excitatory/inhibitory balance, an increase in AMPA/NMDA ratios but no change in paired-pulse ratios, consistent with a postsynaptic increase in excitability in the BLA-vSub circuit. CIE treatment also led to an increase in intrinsic network excitability in the vSub. Overall, our findings suggest a hyperexcitable state in BLA-vSub specific inputs as well as intrinsic inputs to vSub pyramidal neurons which may contribute to the negative affective behaviors associated with CIE.

Different Effects of Alcohol Exposure on Action and Outcome-Related Orbitofrontal Cortex Activity

Alcohol dependence can result in long-lasting deficits to decision-making and action control. Neurobiological investigations have identified orbitofrontal cortex (OFC) as important for outcome-related contributions to goal-directed actions during decision-making. Prior work has shown that alcohol dependence induces long-lasting changes to OFC function that persist into protracted withdrawal and disrupts goal-directed control over actions. However, it is unclear whether these changes in function alter representation of action and outcome-related neural activity in OFC. Here, we used the well-validated chronic intermittent ethanol (CIE) exposure and withdrawal procedure to model alcohol dependence in mice and performed in vivo extracellular recordings during an instrumental task in which lever-press actions made for a food outcome. We found alcohol dependence disrupted goal-directed action control and increased OFC activity associated with lever-pressing but decreased OFC activity during outcome-related epochs. The ability to decode outcome-related information, but not action information, from OFC activity following CIE exposure was reduced. Hence, chronic alcohol exposure induced a long-lasting disruption to OFC function such that activity associated with actions was enhanced, but OFC activity contributions to outcome-related information was diminished. This has important implications for hypotheses regarding compulsive and habitual phenotypes observed in addiction.

Cognitive Remediation as an Adjunct Treatment for Substance Use Disorders: A Systematic Review

Substance use disorders are associated with diverse neuropsychological impairments, with deficits in memory and executive functioning commonly observed. Cognitive remediation has been shown to be effective in other populations with cognitive impairments in these domains, including those with psychiatric disorders and acquired brain injuries, and it has been hypothesised to be similarly effective for those in treatment for substance use disorders. We aimed to systematically review the evidence for cognitive remediation interventions administered as an adjunct treatment to substance use rehabilitation. Studies were included if participants were receiving substance use treatment, if improving cognitive functioning was the main focus of the intervention and if they used an experimental design with a control condition receiving treatment-as-usual or an active control intervention. Two independent reviewers agreed on the final selection of 32 studies, encompassing cognitive remediation for working memory, memory, executive functioning and general cognition. Significant differences between intervention and control groups for cognitive test results and treatment outcomes were extracted and compared across treatment approaches. The review found considerable heterogeneity across studies, including in the types of interventions, the nature of participants and the outcome measures used. Further, a lack of quality studies with sufficient power meant that limited conclusions could be drawn, highlighting a need for further replication and research. However, findings indicate that cognitive remediation remains a promising potential avenue for improving cognition and treatment outcomes for those in treatment for substance use disorders. Protocol submitted prospectively to PROSPERO 30.09.2019, CRD42020150978.

The effects of substance use and physical activity on cognition: The impact of incongruent health behaviors

BACKGROUND

Cognitive functioning refers to storage and manipulation of information and includes executive functioning (EF) and attention (ATT). While physical activity (PA) improves cognitive functioning, decrements are associated with frequent substance use. This study examined PA on cognitive functioning within the context of past-year substance use.

METHODS

Using NESARC-III data (N = 36,309), cross-sectional analysis examined interactions between self-reported past-year PA and substance use in relation to cognitive functioning.

RESULTS

As hypothesized, light-to-moderate, vigorous, and total PA conditional main effects were positively associated with both facets of cognition, while frequent substance use conditional main effects were negatively associated with ATT and EF. The positive association between PA and cognition was diminished by substance use. Frequent binge drinking, marijuana, cocaine, and opioid use weakened the impact of light-to-moderate PA on EF, and only frequent cocaine use lessened the relationship between vigorous PA on EF. When PA intensities were combined, frequent binge drinking and cocaine use weakened the PA and EF association. Infrequent stimulant use reduced the association between all levels of PA and ATT, while infrequent marijuana use unexpectedly enhanced the relation between vigorous PA and ATT.

CONCLUSIONS

Overall, PA enhanced two facets of cognitive functioning across six substances. However, these benefits are reduced in the context of frequency of substance use. The positive association between light-to-moderate PA and EF appears to be more sensitive in the context of frequent substance use than vigorous PA. Implications for public health messaging and PA as cognitive remediation treatment for substance use disorders are discussed.

Effects of an integrated intervention program for alcoholism (IIPA) on learning, memory and quality of life (QOL) in persons with alcohol dependence at the Centre for Addiction Medicine, Bengaluru, India

Purpose

This study aims to examine the effectiveness of an integrated intervention program for alcoholism (IIPA) for improving verbal encoding and memory, visuospatial construction, visual memory and quality of life (QoL) in persons with alcohol dependence.

Design/methodology/approach

The sample comprised treatment-seeking alcohol-dependent persons (n = 50), allotted into two groups: (1) the treatment as usual (TAU) group (n = 25) and (2) the treatment group (n = 25)]. The groups were matched on age (±1 year) and education (±1 year). The TAU group received standard pharmacological treatment, psychotherapeutic sessions on relapse prevention and yoga for 18 days, while the treatment group received IIPA sessions in addition to the usual treatment. Auditory verbal learning test, complex figure test and QoL scale were administered at pre- and post-treatment along with screening measures.

Findings

The two groups were comparable on demographic variables, clinical characteristics and outcome measures at baseline. Pre- to post-treatment changes (gain scores) comparison between the treatment and TAU groups revealed a significant difference in verbal encoding, verbal and visual memory, verbal recognition, visuospatial construction and QoL.

Research limitations/implications

This study suggests that IIPA is effective for improving learning and memory in both modality (verbal and visual) and QoL in persons with alcoholism. The IIPA may help in better treatment recovery.

Practical implications

The IIPA may help in treatment for alcoholism and may enhance treatment efficacy.

Originality/value

IIPA is effective for improving learning and memory in both modalities and QoL in persons with alcohol dependence. The IIPA may help in better treatment recovery.

Suicide Risk and Addiction: The Impact of Alcohol and Opioid Use Disorders

Purpose of Review

Suicide is a major public health concern and a leading cause of death in the US. Alcohol and opioid use disorders (AUD/OUD) significantly increase risk for suicidal ideation, attempts, and death, and are the two most frequently implicated substances in suicide risk. We provide a brief overview of shared risk factors and pathways in the pathogenesis of AUD/OUD and suicidal thoughts and behaviors. We also review clinical recommendations on inpatient care, pharmacotherapy, and psychotherapeutic interventions for people with AUD/OUD and co-occurring suicidal ideation and behavior.

Recent Findings

Among people with an underlying vulnerability to risk-taking and impulsive behaviors, chronic alcohol intoxication can increase maladaptive coping behaviors and hinder self-regulation, thereby increasing the risk of suicide. Additionally, chronic opioid use can result in neurobiological changes that lead to increases in negative affective states, jointly contributing to suicide risk and continued opioid use. Despite significantly elevated suicide risk in individuals with AUD/OUD, there is a dearth of research on pharmacological and psychosocial interventions for co-occurring AUD/OUD and suicidal ideation and behavior.

Summary

Further research is needed to understand the effects of alcohol and opioid use on suicide risk, as well as address notable gaps in the literature on psychosocial and pharmacological interventions to lower risk for suicide among individuals with AUD/OUD.

Meta-analysis of grey matter changes and their behavioral characterization in patients with alcohol use disorder

Alcohol Use Disorder (AUD) is associated with reductions in grey matter (GM) volume which can lead to changes in numerous brain functions. The results of previous studies on altered GM in AUD differ considerably in the regions identified. Three meta-analyses carried out between 2014 and 2017 yielded different results. The present study includes the considerable amount of newer research and delivers a state-of-the art meta-analysis in line with recently published guidelines. Additionally, we behaviorally characterized affected regions using fMRI metadata and identified related brain networks by determining their meta-analytic connectivity patterns. Twenty-seven studies with 1,045 AUD patients and 1,054 healthy controls were included in the analysis and analyzed by means of Anatomical Likelihood Estimation (ALE). GM alterations were identified in eight clusters covering different parts of the cingulate and medial frontal gyri, paracentral lobes, left post- and precentral gyri, left anterior and right posterior insulae and left superior frontal gyrus. The behavioral characterization associated these regions with specific cognitive, emotional, somatosensory and motor functions. Moreover, the clusters represent nodes within behaviorally relevant brain networks. Our results suggest that GM reduction in AUD could disrupt network communication responsible for the neurocognitive impairments associated with high chronic alcohol consumption.

Altered Cerebro-Cerebellar Dynamic Functional Connectivity in Alcohol Use Disorder: a Resting-State fMRI Study

Alcohol use disorder (AUD) is widely associated with cerebellar dysfunction and altered cerebro-cerebellar functional connectivity (FC) that lead to cognitive impairments. Evidence for this association comes from resting-state functional magnetic resonance imaging (rsfMRI) studies that assess time-averaged measures of FC across the duration of a typical scan. This approach, however, precludes the assessment of potentially FC dynamics happening at faster timescales. In this study, using rsfMRI data, we aim at exploring cerebro-cerebellar FC dynamics in AUD patients (N = 18) and age- and sex-matched controls (N = 18). In particular, we quantified group-level differences in the temporal variability of FC between the posterior cerebellum and large-scale cognitive systems, and we investigated the role of the cerebellum in large-scale brain dynamics in terms of the temporal flexibility and integration of its regions. We found that, relative to controls, the AUD group exhibited significantly greater FC variability between the cerebellum and both the frontoparietal executive control (F_1,31 = 7.01, p(FDR) = 0.028) and ventral attention (F_1,31 = 7.35, p(FDR) = 0.028) networks. Moreover, the AUD group exhibited significantly less flexibility (F_1,31 = 8.61, p(FDR) = 0.028) and greater integration (F_1,31 = 9.11, p(FDR) = 0.028) in the cerebellum. Finally, in an exploratory analysis, we found distributed changes in the dynamics of canonical large-scale networks in AUD. Overall, this study brings evidence of AUD-related alterations in dynamic FC within major cerebro-cerebellar networks. This pattern has implications for explaining the development and maintenance of this disorder and improving our understating of the cerebellum's involvement in addiction.

Pharmacological enhancing agents targeting cognition in patients with alcohol-induced neurocognitive disorders: A systematic review

Debilitating neurocognitive deficits are seen in alcohol use disorders (AUD) and Wernicke-Korsakoff's syndrome (WKS). These shared characteristics suggest a spectrum of alcohol-induced neurocognitive disorders (AIND). Cognitive pharmacological enhancing agents (CPEA) have been examined in the treatment of other psychiatric disorders, but little is known about the effects of these agents on AINDs. Our aim was to synthesize the evidence for the effectiveness of CPEAs on AINDs. Databases were searched for controlled trials examining CPEAs on AUD, WKS, and alcohol-related dementia (ARD). Eligible studies were included in a qualitative synthesis and a quality assessment was conducted. The search identified 23 studies (4 ≤ ns ≤ 98). Evidence suggests that modafinil may improve executive functions in AUD and ARD, but this effect may only be present in patients with severe deficits. The studies were rated as having a moderate risk of bias. Despite the promising effects of modafinil, small samples and inconsistent evidence deem the results preliminary. More research is warranted examining the effects of transdiagnostic CPEAs on deficits across AINDs.

The impact of emotional face stimuli on working memory performance among men and women with alcohol use disorder

BACKGROUND

Individuals with alcohol use disorder (AUD) often display compromise in emotional processing and non-affective neurocognitive functions. However, relatively little empirical work explores their intersection. In this study, we examined working memory performance when attending to and ignoring facial stimuli among adults with and without AUD. We anticipated poorer performance in the AUD group, particularly when task demands involved ignoring facial stimuli. Whether this relationship was moderated by facial emotion or participant sex were explored as empirical questions.

METHODS

Fifty-six controls (30 women) and 56 treatment-seekers with AUD (14 women) completed task conditions in which performance was advantaged by either attending to or ignoring facial stimuli, including happy, neutral, or fearful faces. Group, sex, and their interaction were independent factors in all models. Efficiency (accuracy/response time) was the primary outcome of interest.

RESULTS

An interaction between group and condition (F1,107 = 6.03, p < .02) was detected. Individual comparisons suggested this interaction was driven by AUD-associated performance deficits when ignoring faces, whereas performance was equivalent between groups when faces were attended. Secondary analyses suggested little influence of specific facial emotions on these effects.

CONCLUSIONS

These data provide partial support for initial hypotheses, with the AUD group demonstrating poorer working memory performance conditioned on the inability to ignore irrelevant emotional face stimuli. The absence of group differences when scenes were to be ignored (faces remembered) suggests the AUD-associated inability to ignore irrelevance is influenced by specific stimulus qualities.

Emotional processes in binge drinking: A systematic review and perspective

Binge drinking is a widespread alcohol consumption pattern commonly engaged by youth. Here, we present the first systematic review of emotional processes in relation to binge drinking. Capitalizing on a theoretical model describing three emotional processing steps (emotional appraisal/identification, emotional response, emotional regulation) and following PRISMA guidelines, we considered all identified human studies exploring emotional abilities among binge drinkers. A literature search was conducted in PubMed, Scopus, and PsychINFO, and a standardized methodological quality assessment was performed for each study. The main findings offered by the 43 studies included are: 1) regarding emotional appraisal/identification, binge drinking is related to heightened negative emotional states, including greater severity of depressive and anxiety symptoms, and have difficulties in recognizing emotional cues expressed by others; 2) regarding emotional response, binge drinkers exhibit diminished emotional response compared with non-binge drinkers; 3) regarding emotional regulation, no experimental data currently support impaired emotion regulation in binge drinking. Variability in the identification and measurement of binge drinking habits across studies limits conclusions. Nevertheless, current findings establish the relevance of emotional processes in binge drinking and set the stage for new research perspectives to identify the nature and extent of emotional impairments in the onset and maintenance of excessive alcohol use.

The Impact of Acute Exercise Timing on Memory Interference

This study evaluated whether the timing of acute exercise can attenuate a memory interference effect. Across two experiments, participants completed an AB/AC memory task. Participants studied eight word pairs; four denoted AB (e.g., Hero - Apple) and four control (DE) pairs. Following this List 1, participants studied eight additional word pairs (List 2); four denoted AC, re-using words from the AB pairs (e.g., Hero - Project) and four control (FG) pairs. Following their study of both lists, participants completed a cued recall assessment. In Experiment 1 (N = 100), an acute exercise bout occurred before the AB/AC memory interference task, and the participants' three lab visits (successive conditions) were control, moderate-intensity (50% HRR; heart rate reserve) exercise, and vigorous-intensity (80% HRR) exercise. In Experiment 2 (N = 68), the acute exercise occurred between List 1 and List 2, and the participants' two lab visits (successive conditions) were a (80% HRR) vigorous-intensity exercise visit and a control visit. Across both experiments, we observed evidence of both proactive and retroactive interference (p < .05), but acute exercise, regardless of intensity, did not attenuate this interference (p > .05). Acute moderate-intensity exercise was better than control or vigorous-intensity exercise in enhancing associative memory (p < .05), independent of interference. In Experiment 2, vigorous intensity exercise was associated with more pronounced interference (p < .05). Our results suggest that acute exercise can enhance associative memory performance, with no attenuation of interference by exercise.

Do Social Cognition Deficits Recover with Abstinence in Alcohol-Dependent Patients?

Background

Despite growing evidence of the presence and clinical relevance of deficits in social cognition in individuals with alcohol use disorder (AUD), less is known about the potential of “natural” recovery with abstinence in this neurocognitive domain. This study investigated the abstinence‐based recovery of neurocognitive social abilities in alcohol‐dependent patients (ADP) using a prospective longitudinal design with follow‐up assessment under controlled conditions of abstinence during alcohol dependence inpatient treatment.

Methods

Seventy‐seven participants (42 ADP and 35 healthy controls [HC]) performed social cognition testing, including facial emotion recognition, perspective taking, and affective responsiveness twice (baseline/T1 and follow‐up/T2) during comparable follow‐up periods. Assessment of social cognition in abstinent ADP was conducted at the beginning (T1; within the first 2 weeks) and at the end (T2; within the last 2 weeks) of long‐term (2 months) abstinence‐oriented alcohol dependence inpatient treatment. Only patients abstinent for >14 days (last heavy drinking day >21 days) at baseline (T1) and who remained abstinent at follow‐up (T2) were included.

Results

ADP, who on average were nearly 2 months abstinent at T1, showed poorer social cognition in all 3 areas (emotion recognition, perspective taking, and affective responsiveness) than HC. There was no difference between groups on the change in performance over time, and group differences (ADP vs. HC) remained significant at T2, indicating persistent social cognition deficits in ADP following controlled abstinence during inpatient treatment.

Conclusions

Our findings indicate no natural recovery of social cognition impairments in ADP during an intermediate to long‐term period of abstinence (2+ months), the usual active treatment phase. Research aimed at developing interventions that focus on the improvement of social cognition deficits (e.g., social cognition training) and determining whether they benefit short‐ and long‐term clinical outcomes in AUD seems warranted.

Neuroimaging and Cognitive Evidence for Combined HIV-Alcohol Effects on the Central Nervous System: A Review

Alcohol use disorder (AUD) among people living with HIV (PLWH) is a significant public health concern. Despite the advent of effective antiretroviral therapy, up to 50% of PLWH still experience worsened neurocognition, which comorbid AUD exacerbates. We report converging lines of neuroimaging and neuropsychological evidence linking comorbid HIV/AUD to dysfunction in brain regions linked to executive function, learning and memory, processing speed, and motor control, and consequently to impairment in daily life. The brain shrinkage, functional network alterations, and brain metabolite disruption seen in individuals with HIV/AUD have been attributed to several interacting pathways: viral proteins and EtOH are directly neurotoxic and exacerbate each other's neurotoxic effects; EtOH reduces antiretroviral adherence and increases viral replication; AUD and HIV both increase gut microbial translocation, promoting systemic inflammation and HIV transport into the brain by immune cells; and HIV may compound alcohol's damaging effects on the liver, further increasing inflammation. We additionally review the neurocognitive effects of aging, Hepatitis C coinfection, obesity, and cardiovascular disease, tobacco use, and nutritional deficiencies, all of which have been shown to compound cognitive changes in HIV, AUD, and in their comorbidity. Finally, we examine emerging questions in HIV/AUD research, including genetic and cognitive protective factors, the role of binge drinking in HIV/AUD-linked cognitive decline, and whether neurocognitive and brain functions normalize after drinking cessation.

Physical activity: A promising adjunctive treatment for severe alcohol use disorder

Substance use disorder develops from complex interactions between socio-environmental and neurobiological factors. A neurocognitive model of addiction, the triadic model, proposes that Alcohol Use Disorder (AUD) is the result of an imbalance between the reflective and the impulsive subcomponents along with a disruption of the regulatory subcomponent. Physical activity is considered as an emerging treatment for severe AUD (sAUD). This short review examines the efficacy and mechanisms of action of physical intervention as an adjunctive treatment in severe AUD (sAUD) within the theoretical framework of the triadic model. Physical activity is a feasible, safe, and less stigmatizing approach than classical treatments. It improves sAUD patients' mental and physical comorbidities. The key finding of this short review is that physical activity could contribute to a rebalancing of the triadic model in sAUD patients by 1) improving neuroplasticity and cognitive functioning, 2) reducing impulsivity and urgency, and improving emotional regulation, and 3) reducing craving. This rebalancing could eventually reduce the risk of relapse. However, due to methodological issues, it remains difficult to observe an effect of physical activity on drinking outcomes. At best, a trend towards a reduction in alcohol consumption was noted. The mechanisms that could explain the benefits of physical activity in sAUD patients involve multiple physiological processes such as dopaminergic or glutamatergic transmission and signaling or neuroplasticity. Future randomized controlled trials should include neuropsychological and impulsivity assessments, in more controlled environments. Physical activity could contribute to a personalization of sAUD treatment using each subcomponent of the triadic model as a therapeutic target. Physical exercise could be an adjunctive treatment for sAUD patients, favoring the benefit of more usual treatments such as cognitive behavioral therapies. It could also be a stand-alone intervention in less severe patients.

Relationship between BMI and alcohol consumption levels in decision making

BACKGROUND

Decision-making deficits in obesity and alcohol use disorder (AUD) may contribute to the choice of immediate rewards despite their long-term deleterious consequences.

METHODS

Gambling task functional MRI in Human connectome project (HCP) dataset was used to investigate neural activation differences associated with reward or punishment (a key component of decision-making behavior) in 418 individuals with obesity (high BMI) and without obesity (lean BMI) and either at high (HR) or low (LR) risk of AUD based on their alcohol drinking levels.

RESULTS

Interaction between BMI and alcohol drinking was seen in regions of the default mode network (DMN) and those implicated in self-related processing, memory, and salience attribution. ObesityHR relative to obesityLR also recruited DMN along with primary motor and regions implicated in inattention, negative perception, and uncertain choices, which might facilitate impulsive choices in obesityHR. Furthermore, obesityHR compared to leanHR/leanLR also demonstrated heightened activation in DMN and regions implicated in uncertain decisions.

CONCLUSIONS

These results suggest that BMI is an independent variable from that of alcohol drinking levels in neural processing of gambling tasks. Moreover, leanLR relative to leanHR, showed increased activation in motor regions [precentral and superior frontal gyrus] suggestive of worse executive function from excessive alcohol use. Delayed discounting measures failed to distinguish between obesity and high alcohol drinking levels, which as for gambling task results suggests independent negative effects of obesity and chronic alcohol drinking on decision-making. These findings highlight distinct associations of obesity and high-risk alcohol drinking with two key constituents of decision-making behavior.

Component process analysis of verbal memory in a sample of students with a binge drinking pattern

Background

Many studies have emphasized the harmful impact of binge drinking on several cognitive functions, including memory. However, the exact nature of the memory processes involved is still unknown. The present study was designed to assess verbal working memory and verbal episodic memory, especially its encoding, storage and retrieval processes, in binge drinking to identify the processes impacted by this behavior.

Methods

Participants were 48 community-recruited college students aged 18-25 years and categorized as either binge drinkers (BDs) or social drinkers (SDs). They were assessed with (a) subtests of the Wechsler scale (digit span, letter-number sequencing) measuring verbal working memory, and (b) a modified version of the Free and Cued Selective Reminding Test (FCSRT), which measures verbal episodic memory functioning in various conditions of encoding (controlled) and recollection (free recall, cued recall, and recognition).

Results

Verbal working memory was unaffected by binge drinking, whereas verbal episodic memory performances were reduced. In particular, analysis of the modified FCSRT scores suggested that BDs had less proficient storage and retrieval processes. Furthermore, correlational analyses indicated that the proficiency of these memory components was negatively correlated with several indicators of binge drinking behavior.

Conclusions

Results suggest that binge drinking behavior affects the storage and recollection processes of verbal episodic memory. The academic failure described in binge drinkers could be partly related to this harmful effect. Our results on the negative impact of binge drinking on memory should be used to develop information campaigns targeting students.

Effects of Exercise on Explicit Memory Function: Incidental and Intentional Encoding May Depend on Exercise Timing

The present experiment evaluated the effects of self-reported exercise behavior and an acute bout of high-intensity exercise on explicit memory function. The memory tasks were encoded either incidentally or intentionally; for intentional encoding, participants were told to focus on memorizing the stimuli (words), whereas for incidental encoding, participants were unaware that they would be subsequently asked to complete an object recognition task. Among a sample of 150 adults (M_age = 20 years), randomly assigned experimental participants engaged in the following task sequence: (a) incidentally encoded a series of objects, (b) engaged in 20 minutes of high-intensity exercise, (c) intentionally encoded a word list, and (d) completed explicit memory retrieval tasks. Control group participants viewed a time matched video in lieu of high intensity exercise. We measured self-reported exercise behavior via an exercise questionnaire. We did not observe convincing evidence of an effect of high-intensity acute exercise, when occurring during the early consolidation period, on memory function, for either incidental or intentional encoding tasks. However, self-reported engagement in moderate-to-vigorous physical activity was favorably associated with explicit memory performance.

Brain Structure and Function in Recovery

Alcohol use disorder (AUD) commonly is associated with compromise in neurobiological and/or neurobehavioral processes. The severity of this compromise varies across individuals and outcomes, as does the degree to which recovery of function is achieved. This narrative review first summarizes neurobehavioral, neurophysiological, structural, and neurochemical aberrations/deficits that are frequently observed in people with AUD after detoxification. Subsequent sections review improvements across these domains during recovery, taking into account modulators of recovery to the extent permitted. Where appropriate, the discussion includes work integrating outcomes across domains, leveraging the strengths of diverse experimental methods. Interventions to ameliorate neurobiological or neurobehavioral deficits do not constitute a primary objective of this review. However, their consideration is a logical inclusion. Therefore, a limited introduction to existing methods is also presented.

Knowledge of Prevention Measures and Information About Coronavirus in Romanian Male Patients with Severe Mental Illness and Severe Alcohol Use Disorder

PURPOSE

Patients with severe mental illness (SMI) and alcohol use disorder (AUD) are at higher risk for contracting coronavirus-19 (COVID-19) and for poor outcomes of COVID-19 infection. One reason for this could be the lack of knowledge regarding preventive measures against COVID-19 and the inability of the psychiatric patients to discern misinformation from facts.

PATIENTS AND METHODS

The study design was cross-sectional. We applied one questionnaire that evaluated knowledge of prevention measures and information about COVID-19 (comprised of two sections, each with five questions). The first section evaluated knowledge regarding the official WHO prevention measures against COVID-19, and the second consisted of false information about COVID-19 which examined the ability to identify misinformation about COVID-19. These questionnaires were applied face-to-face to psychiatric male inpatients from a tertiary psychiatric hospital in Bucharest diagnosed with SMI or severe alcohol disorder (SAUD) and to male controls from the community, matched by age and education. Mean scores of patients and controls were compared using Mann-Whitney test.

RESULTS

There were 115 male psychiatric patients in total (65 SMI and 50 SAUD) and 57 controls included after the matching procedure. We found statistically significant lower (P<0.05) scores for psychiatric patients compared to controls regarding the prevention and general knowledge of COVID-19 (P<0.001), the WHO information about prevention measures (P=0.041), and the ability to identify misinformation about COVID-19 (P<0.001). The fact that psychiatric patients have less knowledge about prevention measures against COVID-19 and a reduced capacity to discern misinformation suggests that we need to identify new methods to convey correct information to these patients and also to better equip them to handle misinformation regarding COVID-19.

CONCLUSION

Patients with SMI and SAUD are less informed regarding COVID-19 infection and preventive measures compared to controls, while being prone to believing false information about COVID-19 as well.

Neurocognitive performance in alcohol use disorder using the NIH toolbox: Role of severity and sex differences

AIMS

Sustained heavy alcohol consumption is associated with a range of neurocognitive deficits. Yet, past research centers on a severe profile of alcohol use disorder (AUD), with persons recruited from in-patient settings. The current project aims to compare neurocognitive performance between individuals seeking AUD outpatient treatment with healthy comparisons while considering the association between performance, disorder severity, and sex.

METHODS

Enrollment included two matched groups (N = 125; 34 % female): 77 treatment-seeking individuals with AUD; 48 healthy comparison individuals with low drinking patterns. Neurocognitive performance on NIH Toolbox subtests measuring attention, inhibition, episodic memory, working memory, language, and processing speed were compared across groups. Within the AUD group, analyses examined the relationship between performance, disorder severity, recent alcohol consumption, and sex.

RESULTS

AUD group did not perform significantly lower than healthy comparisons on neurocognition subtests assessed. Within AUD group, females displayed significantly higher processing speeds than males (p = .007). Disorder severity and alcohol consumption were not significantly related to performance. However, a significant interaction between disorder severity and sex emerged (p = .010), with higher severity associated with poorer performance in males but not females, on a subtest measuring attention and inhibition.

CONCLUSIONS

Effect of heavy alcohol use on neurocognitive performance was not detected in this outpatient AUD sample. Weaknesses in domains of attention and inhibition may be correlated with AUD severity among males, but not females. Further research on AUD severity and sex in understanding individual differences in neurocognition is warranted, particularly using novel tools for large scale phenotyping, such as the NIH Toolbox.

Eye Tracking Studies Exploring Cognitive and Affective Processes among Alcohol Drinkers: a Systematic Review and Perspectives

Acute alcohol intoxication and alcohol use disorders are characterized by a wide range of psychological and cerebral impairments, which have been widely explored using neuropsychological and neuroscientific techniques. Eye tracking has recently emerged as an innovative tool to renew this exploration, as eye movements offer complementary information on the processes underlying perceptive, attentional, memory or executive abilities. Building on this, the present systematic and critical literature review provides a comprehensive overview of eye tracking studies exploring cognitive and affective processes among alcohol drinkers. Using PRISMA guidelines, 36 papers that measured eye movements among alcohol drinkers were extracted from three databases (PsycINFO, PubMed, Scopus). They were assessed for methodological quality using a standardized procedure, and categorized based on the main cognitive function measured, namely perceptive abilities, attentional bias, executive function, emotion and prevention/intervention. Eye tracking indexes showed that alcohol-related disorders are related to: (1) a stable pattern of basic eye movement impairments, particularly during alcohol intoxication; (2) a robust attentional bias, indexed by increased dwell times for alcohol-related stimuli; (3) a reduced inhibitory control on saccadic movements; (4) an increased pupillary reactivity to visual stimuli, regardless of their emotional content; (5) a limited visual attention to prevention messages. Perspectives for future research are proposed, notably encouraging the exploration of eye movements in severe alcohol use disorders and the establishment of methodological gold standards for eye tracking measures in this field.

Sustained attention and vigilance deficits associated with HIV and a history of methamphetamine dependence

BACKGROUND

Human immunodeficiency virus (HIV)-associated neurocognitive disorders persist in the era of antiretroviral therapy. One factor that is elevated among persons with HIV (PWH) and independently associated with neurocognitive impairment is methamphetamine dependence (METH). Such dependence may further increase cognitive impairment among PWH, by delaying HIV diagnosis (and thus, antiretroviral therapy initiation), which has been posited to account for persistent cognitive impairment among PWH, despite subsequent treatment-related viral load suppression (VLS; <50 copies of the virus per milliliter in plasma or cerebrospinal fluid). This study examined the main and interactive (additive versus synergistic) effects of HIV and history of METH on the sustained attention and vigilance cognitive domain, while controlling for VLS.

METHODS

Participants included 205 (median age = 44 years; 77% males; HIV-/METH- n = 67; HIV+/METH - n = 49; HIV-/METH+ n = 36; HIV+/METH+ n = 53) individuals enrolled in the Translational Methamphetamine AIDS Research Center, who completed Conners' and the 5-Choice continuous performance tests (CPTs).

RESULTS

METH participants exhibited deficits in sustained attention and vigilance; however, these effects were not significant after excluding participants who had a positive urine toxicology screen for methamphetamine. Controlling for VLS, PWH did not have worse sustained attention and vigilance, but consistently displayed slower reaction times across blocks, relative to HIV- participants. There was no HIV x METH interaction on sustained attention and vigilance.

CONCLUSIONS

Recent methamphetamine use among METH people and detectable viral loads are detrimental to sustained attention and vigilance. These findings highlight the need for prompt diagnosis of HIV and initiation of antiretroviral therapy, and METH use interventions.

Onset Age of Substance Use and Neuropsychological Performance in Hospital Patients

OBJECTIVE

Several studies have found neurocognitive deficits in adolescents following substance abuse. Predisposing risk factors may further impact vulnerability to neurocognitive deficits. Little is known about the cognitive performance of adult onset substance users compared to earlier onset users. This study aims to explore differences in neuropsychological functioning between early (EOAs) and late onset substance abusers (LOAs) when the effects of confounding factors are controlled.

METHOD

Data for this cross-sectional study was collected from hospital patients. A total of 164 patients with substance use disorder (SUD) aged 19 to 65, 76 with single-drug diagnosis and 88 with multidrug diagnosis, underwent neuropsychological tests for verbal capacity, attention, speed of processing, perceptual reasoning, memory and learning, executive functioning, and inhibitory capacity. Associations between regular onset age and neuropsychological measures were analysed using in multi-way ANCOVA, and the effect of age, multiple substance abuse, education level and learning difficulties were controlled.

RESULTS

Compared with LOAs, EOAs had weaker performance in the Digit Symbol test for mono-substance users. Meanwhile, compared with EOAs, LOAs had weaker performance in the Delayed Visual Memory test and the Raven test for mono-substance users, and the Block Design test for poly-substance users. From the confounding factors, early onset age of substance use is heightened among individuals with learning disabilities.

CONCLUSIONS

Onset age of substance use is related to the deterioration of performance in neuropsychological tests. Premorbid poor learning and inhibitory capacity may be important predisposing risk factors of SUD. Conversely, high level of education may be a protective factor for cognitive performance in patients with SUD.

Alcohol's Unique Effects on Cognition in Women: A 2020 (Re)view to Envision Future Research and Treatment

Alcohol use and misuse is increasing among women. Although the prevalence of drinking remains higher in men than women, the gender gap is narrowing. This narrative review focuses on the cognitive sequelae of alcohol consumption in women. Studies of acute alcohol effects on cognition indicate that women typically perform worse than men on tasks requiring divided attention, memory, and decision-making. Beneficial effects of moderate alcohol consumption on cognition have been reported; however, a number of studies have cautioned that other factors may be driving that association. Although chronic heavy drinking affects working memory, visuospatial abilities, balance, emotional processing, and social cognition in women and men, sex differences mark the severity and specific profile of functional deficits. The accelerated or compressed progression of alcohol-related problems and their consequences observed in women relative to men, referred to as "telescoping," highlights sex differences in the pharmacokinetics, pharmacodynamics, cognitive, and psychological consequences of alcohol. Brain volume deficits affecting multiple systems, including frontolimbic and frontocerebellar networks, contribute to impairment. Taken together, sex-related differences highlight the complexity of this chronic disease in women and underscore the relevance of examining the roles of age, drinking patterns, duration of abstinence, medical history, and psychiatric comorbidities in defining and understanding alcohol-related cognitive impairment.

A randomized pilot trial of topiramate for alcohol use disorder in veterans with traumatic brain injury: Effects on alcohol use, cognition, and post-concussive symptoms

BACKGROUND

Topiramate is an effective treatment for alcohol use disorder (AUD) and has also been used in the care of mild traumatic brain injury (mTBI). This pilot study aimed to obtain a preliminary assessment of topiramate's efficacy in reducing alcohol use and post-concussive symptoms, and its potential negative impact on cognitive function in 32 Veterans with co-occurring AUD and mTBI.

METHODS

This was a prospective 12-week, randomized, double-blind, placebo-controlled pilot study of flexible-dose topiramate or placebo. Primary outcome was reduction of drinking days per week within the topiramate arm. Secondary outcomes included between group comparisons of alcohol use and craving, post-concussive symptoms, and cognitive function.

RESULTS

Drinking days per week significantly decreased within both the topiramate and placebo arm. There were no significant treatment-by-week interactions on alcohol use/craving, or post-concussive symptoms in intent-to-treat analyses. In per-protocol analyses, topiramate significantly reduced number of drinks per week compared with placebo. Topiramate transiently impaired verbal fluency and working memory. Processing speed, cognitive inhibition, and mental flexibility significantly improved between weeks 1 and 12, regardless of treatment arm.

CONCLUSIONS

Significant improvement occurred in both the topiramate and placebo groups over 12 weeks of treatment in alcohol use and post-concussive symptoms. Among treatment completers there was greater reduction of alcohol use in the topiramate arm. Topiramate was also associated with negative but transient effects on cognitive function. Results suggest both a possible benefit for topiramate treatment in reducing alcohol use and some potential for negative cognitive effects in Veterans with AUD and mTBI.

Dose-dependent effects of alcohol injections on omission-contingency learning have an inverted-U pattern

Previous examinations of the long-term effects of alcohol exposure on omission-contingency learning have produced mixed results across different age or sex groups, with evidence for faster learning or no effect. However, none of these experiments made comparisons using the same exposure-dose across the age/sex groups. Here, we exposed rats to 6 weeks of alcohol injections (3 days/week, 1.75 or 3.5 g/kg/24-h, i.p. broken up into 2 injections/day) in adolescent/early adult males or females (PND27-66) or adult males (PND62-101). We then tested the rats in autoshaping and omission-contingency tasks. In contrast to our hypotheses, the low 1.75-g/kg/24-h dose led to slower omission learning and the higher 3.5-g/kg/24-h dose had no effect. There were no age- or sex-differences in omission learning. Additionally, during autoshaping training, rats exposed in adolescence/early adulthood had a faster shift to sign-tracking in their sign-tracking/goal-tracking ratios than rats exposed in adulthood, with no consistent effect of alcohol exposure or sex-differences. Our results suggest complex effects of alcohol on the neural substrates of omission-contingency learning at different doses, which will require future investigation.

The effect of alcohol withdrawal syndrome severity on sleep, brain and cognition

In alcohol use disorder, drinking cessation is frequently associated with an alcohol withdrawal syndrome. Early in abstinence (within the first 2 months after drinking cessation), when patients do not exhibit physical signs of alcohol withdrawal syndrome anymore (such as nausea, tremor or anxiety), studies report various brain, sleep and cognitive alterations, highly heterogeneous from one patient to another. While the acute neurotoxicity of alcohol withdrawal syndrome is well-known, its contribution to structural brain alterations, sleep disturbances and neuropsychological deficits observed early in abstinence has never been investigated and is addressed in this study. We included 54 alcohol use disorder patients early in abstinence (from 4 to 21 days of sobriety) and 50 healthy controls. When acute physical signs of alcohol withdrawal syndrome were no longer present, patients performed a detailed neuropsychological assessment, a T₁-weighted MRI and a polysomnography for a subgroup of patients. According to the severity of the clinical symptoms collected during the acute withdrawal period, patients were subsequently classified as mild alcohol withdrawal syndrome (mild-AWS) patients (Cushman score ≤ 4, no benzodiazepine prescription, N = 17) or moderate alcohol withdrawal syndrome (moderate-AWS) patients (Cushman score > 4, benzodiazepine prescription, N = 37). Patients with severe withdrawal complications (delirium tremens or seizures) were not included. Mild-AWS patients presented similar grey matter volume and sleep quality as healthy controls, but lower processing speed and episodic memory performance. Compared to healthy controls, moderate-AWS patients presented non-rapid eye movement sleep alterations, widespread grey matter shrinkage and lower performance for all the cognitive domains assessed (processing speed, short-term memory, executive functions and episodic memory). Moderate-AWS patients presented a lower percentage of slow-wave sleep, grey matter atrophy in fronto-insular and thalamus/hypothalamus regions, and lower short-term memory and executive performance than mild-AWS patients. Mediation analyses revealed both direct and indirect (via fronto-insular and thalamus/hypothalamus atrophy) relationships between poor sleep quality and cognitive performance. Alcohol withdrawal syndrome severity, which reflects neurotoxic hyperglutamatergic activity, should be considered as a critical factor for the development of non-rapid eye movement sleep alterations, fronto-insular atrophy and executive impairments in recently detoxified alcohol use disorder patients. The glutamatergic activity is involved in sleep-wake circuits and may thus contribute to molecular mechanisms underlying alcohol-related brain damage, resulting in cognitive deficits. Alcohol withdrawal syndrome severity and sleep quality deserve special attention for a better understanding and treatment of brain and cognitive alterations observed early in abstinence, and ultimately for more efficient relapse prevention strategies.

Motor behavior-induced prefrontal cortex activation and episodic memory function

BACKGROUND

The objective of this paper was to evaluate the potential individual and combined effects of acute exercise coupled with bilateral interhemispheric activation on episodic memory function. Six experiments were conducted.

METHODS

Experiment 1 was a within-subject, counterbalanced experiment. Participants completed four visits, including 1) exercise and saccadic eye movements, 2) exercise only, 3) saccadic eye movements only, and 4) no exercise and no saccadic eye movements (control). A word-list memory assessment was employed, including a long-term (20-min delay) memory evaluation. In Experiment 2, we evaluated the effects of saccadic eye movements on prefrontal cortex oxygenation, a proxy for neuronal activity. Similarly, in our third experiment, we evaluated the effects of acute exercise on prefrontal cortex oxygenation. Thus, experiments 2 and 3 were employed to provide mechanistic insights from the results shown in experiment 1. Experiment 4 replicated Experiment 1, but instead of increasing prefrontal cortex activation via saccadic eye movements, we used a fist clenching protocol. Experiment 5 evaluated the effects of fist clenching on prefrontal cortex oxygenation.

RESULTS

Collectively, these 5 experimental studies showed that acute exercise (Experiment 1), saccadic eye movements (Experiment 1), and fist clenching (Experiment 4) enhanced memory function, and that acute exercise (Experiment 3), saccadic eye movements (Experiment 2) and fist clenching (Experiment 5) all increased prefrontal cortex oxygenation. Experiment 6 demonstrated that prefrontal cortex oxygenation was positively associated with episodic memory function.

CONCLUSION

These six experiments suggest that several behaviors, such as acute exercise, saccadic eye movements and fist clenching may improve memory function and may, potentially, do so via increases in prefrontal cortex oxygenation.

Memory biases in alcohol use disorder: enhanced memory for contexts associated with alcohol prospectively predicts alcohol use outcomes

Memory for prior drinking experiences may powerfully drive later alcohol use in familiar drinking contexts, yet we know little about what patients with alcohol use disorder (AUD) remember of alcohol-related episodes. Although animal and theoretical models of addiction emphasize the importance of different memory systems for understanding maladaptive use, clinical research parsing what AUD patients remember from alcohol-related episodes is lacking. The current study applied a novel memory task in which moderate drinkers (N = 30) and treatment-seeking individuals with alcohol use disorder (AUD: N = 29) encoded associations between photographs of objects (alcoholic beverages and neutral items) and photographs of neutral scenes. At least 24 h later, two types of memory were assessed: item memory (object recognition) and associative memory (cued recognition of scenes associated with objects). To assess which memories predicted drinking, real-world behavior was assessed in patients with AUD at baseline and for 4 weeks following memory tests. Despite demographic differences, the results showed broadly impaired item memory in AUD compared with moderate drinkers (p < 0.001), but enhanced associative memory for scenes paired with alcohol (p = 0.015). These associative memory biases were especially pronounced for stimuli rated as more affectively salient. Furthermore, stronger but less detailed memory for alcohol-related associations (i.e., choosing the correct scene but the incorrect photograph) significantly predicted heavier baseline (p = 0.002) and higher subsequent (p = 0.01) drinking in patients with AUD. These findings reveal a novel alcohol-related memory bias in AUD, and uncover the importance of associative memory for understanding real-world heavy alcohol use.

Socio-affective processing biases in severe alcohol use disorders: Experimental and therapeutic perspectives

Previous literature has consistently reported socio-affective information processing impairments in patients with severe alcohol use disorder (SAUD). Some recent studies have also suggested that these patients might exhibit biases toward stimuli indicating social threat, such as angry or disgusted faces. Such biases have been largely documented in other psychopathological disorders like anxiety, where they play a critical role in the emergence and maintenance of the disorder. A comprehensive understanding of these biases in SAUD would thus deepen the understanding of interpersonal difficulties and relapse-related factors. However, to date, no study has directly explored these biases in SAUD. In order to initiate efforts to address this issue, we first review preliminary evidence supporting the hypothesis of biased processing of social threat in SAUD. Then, we identify possible pathways through which such biases might negatively impact the course of the disorder. Finally, we provide precise recommendations and available materials to develop research in this promising field, and underline the related theoretical and clinical perspectives.

Impact of polysubstance use on social and non-affective cognitive performance among treatment-seeking individuals with alcohol use disorders

BACKGROUND

Individuals with alcohol use disorder (AUD) display deficits across a range of cognitive processes. Decrements in social cognition may be particularly important for interpersonal functioning and post-treatment adaptation. Although social cognitive deficits are associated with chronic use of numerous substances, the role of polysubstance use in AUD-associated deficits remains largely unaddressed.

METHODS

Community volunteers (n = 49; 22 men) and inpatient treatment-seekers with AUD were administered neurocognitive tasks indexing emotion processing and non-affective cognitive functioning. Tasks included an emotion discrimination task, a working memory task with affective stimuli, a general face processing (control) task, two measures of executive function, and two measures of visual spatial function. AUD subgroups included individuals with no recent (6-month) polysubstance use (AUD-Only; n = 22; 15 men), and those with at least weekly use (Poly-SU; n = 22; 18 men).

RESULTS

Poly-SU individuals evinced disadvantaged performance relative to other groups on the emotion discrimination task [ps ≤ 0.001], affective working memory task [ps ≤ 0.050], and two executive function measures [ps ≤ 0.051]. No differences were observed for visual spatial functioning [ps ≥ 0.498] or general face processing [ps ≥ 0.190]. No performance differences between AUD-Only and community volunteers were noted.

CONCLUSIONS

Results extend the emerging literature exploring emotion processing in AUD and add to the established literature regarding cognitive deficits in this population. The data suggest that among individuals with AUD, those with polysubstance use may be particularly vulnerable to deficits in decoding emotional face content. The current work highlights the need to incorporate more nuanced and careful considerations of polysubstance use in the design and analysis for future investigations of alcohol-associated deficits in emotion processing.

Cognitive impairment in individuals with bipolar disorder with and without comorbid alcohol and/or cocaine use disorders

BACKGROUND

Bipolar disorder (BD) frequently co-occurs with substance use disorders (SUDs), and both are associated with cognitive impairment. This study compares cognition between individuals with BD with and without current alcohol use disorder (AUD), cocaine use disorder (CUD), or both, as these disorders may be linked with additive cognitive impairment.

METHODS

Baseline data were analyzed from five clinical studies of individuals with the aforementioned disorders (N = 373). Participants were grouped as follows: BD-only, BD + AUD, BD + CUD, or BD + AUD + CUD. Cognition was assessed with the Rey Auditory Verbal Learning Test (RAVLT) (verbal learning and memory) and Stroop Color Word Test (executive function). Multiple linear regression models determined if SUD diagnosis, among other demographic and clinical variables, predicted each cognitive test's T-score. Regression equations were used to compute each group's mean T-scores.

RESULTS

All groups demonstrated below-average mean T-scores on all tests, with no significant between-group score differences. RAVLT total T-scores were lower than Stroop color-word T-scores within all groups (non-overlapping 95% confidence intervals). Higher daily cocaine use predicted higher Stroop T-scores (p < 0.01) and RAVLT delayed recall T-scores (p < 0.05). No other non-demographic variable, including AUD/CUD group status, predicted cognitive performance.

LIMITATIONS

A full cognitive battery and some relevant variables (e.g. BD lifetime illness course) were not available. Many participants (42.1%) had additional SUDs.

CONCLUSIONS

BD with and without AUD/CUD was found to be associated with greater deficits in verbal learning and memory than in executive function. Addressing these impaired domains in dually-diagnosed patients may improve treatment and functional outcomes.

Pinpointing Neural Correlates of Attachment in Poly-Drug Use: A Diffusion Tensor Imaging Study

An increasing amount of evidence indicates the significance of attachment in the etiology of poly-drug use disorder (PUD). The aim of this study was to investigate associations between PUD and adult attachment in particular, with a focus on white matter (WM) fiber tract integrity. For this purpose, we selected several regions-of-interest based on previous findings which were examined for their role in PUD and estimated whole-brain associations between adult attachment and WM integrity. A total sample of 144 right-handed males were investigated (Age: M = 27; SD = 4.66). This included a group of patients diagnosed with PUD (n = 70) and a group of healthy controls (HC; n = 74). The Adult Attachment Scales (AAS) was applied to assess attachment attitudes in participants. Diffusion Tensor Imaging was used to investigate differences in WM integrity. The findings suggest substantially less attachment security in PUD patients compared to HC. Furthermore, PUD patients exhibited reduced integrity in WM fiber tracts, most pronounced in the bilateral corticospinal tract, the fronto-occipital fasciculus, and the right inferior longitudinal fasciculus. However, these results were not controlled for comorbid depressiveness. With regard to associations between adult attachment and WM integrity, the results for PUD patients indicate a negative relationship between "Comfort with Closeness" and the structural integrity of a cluster comprising parts of the right anterior thalamic radiation, the inferior fronto-occipital fasciculus and the uncinate fasciculus. Despite being limited by the cross-sectional design of this study, the results emphasize the significance of attachment in PUD etiology, both at a behavioral and a neurological level. Largely in line with previous research, the findings revealed tentative links between adult attachment and WM fiber tracts related to cognitive and affective functions in PUD patients.

Short-term neuropsychological recovery in alcohol use disorder: A retrospective clinical study

BACKGROUND

Neuropsychological impairments found in recently detoxified patients with alcohol use disorder (AUD) can limit the benefit of psychosocial treatments and increase the risk of relapse. These neuropsychological deficits are reversible with abstinence. The aim of this retrospective clinical study was to investigate whether a short-term stay as inpatients in a convalescent home enables neuropsychological deficits observed in recently detoxified AUD patients to recover and even performance to return to normal.

METHODS

Neuropsychological data were collected in 84 AUD patients. Five neuropsychological components were assessed before and after a three-week stay in a convalescent home offering multidisciplinary support. Baseline and follow-up performance were compared in the entire group of patients and in subgroups defined by the nature and intensity of the therapy (OCCASIONAL: occasional occupational and physical therapy; INTENSIVE: intensive occupational and physical therapy and neuropsychological training).

RESULTS

In the entire group of patients, neuropsychological performance significantly improved between baseline and follow-up for all 5 components and even returned to a normal level for 4 of them. The ratio of patients with impaired performance was significantly lower at follow-up than baseline examination for 3 components in the INTENSIVE group only.

CONCLUSION

Recently detoxified AUD patients with cognitive deficits benefit from a short-term stay in an environment ensuring sobriety and healthy nutrition. Cognitive recovery may be enhanced by intensive care including neuropsychological training. Alcohol programs could be postponed in patients with cognitive deficits in order to offer psychosocial treatment when patients are cognitively able to benefit from it.

Selective visual and crossmodal impairment in the discrimination of anger and fear expressions in severe alcohol use disorder

BACKGROUND

Severe alcohol use disorder (SAUD) is associated with impaired discrimination of emotional expressions. This deficit appears increased in crossmodal settings, when simultaneous inputs from different sensory modalities are presented. However, so far, studies exploring emotional crossmodal processing in SAUD relied on static faces and unmatched face/voice pairs, thus offering limited ecological validity. Our aim was therefore to assess emotional processing using a validated and ecological paradigm relying on dynamic audio-visual stimuli, manipulating the amount of emotional information available.

METHOD

Thirty individuals with SAUD and 30 matched healthy controls performed an emotional discrimination task requiring to identify five emotions (anger, disgust, fear, happiness, sadness) expressed as visual, auditory, or auditory-visual segments of varying length. Sensitivity indices (d') were computed to get an unbiased measure of emotional discrimination and entered in a Generalized Linear Mixed Model. Incorrect emotional attributions were also scrutinized through confusion matrices.

RESULTS

Discrimination levels varied across sensory modalities and emotions, and increased with stimuli duration. Crucially, performances also improved from unimodal to crossmodal conditions in both groups, but discrimination for anger crossmodal stimuli and fear crossmodal/visual stimuli remained selectively impaired in SAUD. These deficits were not influenced by stimuli duration, suggesting that they were not modulated by the amount of emotional information available. Moreover, they were not associated with systematic emotional error patterns reflecting specific confusions between emotions.

CONCLUSIONS

These results clarify the nature and extent of crossmodal impairments in SAUD and converge with earlier findings to ascribe a specific role for anger and fear in this pathology.

Acute exercise on memory function: open vs. closed skilled exercise

Background: Previous studies suggest that acute exercise may improve memory function. Few studies, however, have investigated the differential effect of the acute exercise movement patterns on memory. Such an effect is plausible, as research demonstrates that open-skilled exercise (e.g.,racquetball) may have a greater effect on memory-related neurotrophins (e.g., brain-derived neurotrophic factors) when compared to closed-skilled exercise (e.g. treadmill exercise). A key distinction between open- and closed-skilled exercise is that open-skilled exercises are those that require an individual to react in a dynamic way to a changing, unpredictable environment. Our aim in this study was to assess wether retrospective and prospective memory are differentially influenced from open- and closed-skilled acute exercise. Methods: A within-subject design was employed. Participants (Mage = 20.6 years; 69% female)completed two visits, in a counterbalanced order. The two experimental conditions included open-skilled acute exercise (racquetball) and closed-skilled acute exercise (treadmill exercise),each lasting 30-minute at 60% of heart rate reserve (HRR). During both experimental conditions,participants completed short- and long-term assessments of retrospective and prospective memory function. Retrospective memory was evaluated across multiple word-list trials (e.g.,Trials 1-6, 20-minute delay, 24-hour delay). Results: No significant effect of exercise was found on prospective memory. For retrospective memory, there was a significant main effect for condition, F(1, 57) = 5.33, P = 0.02, η2 = 0.004,main effect for trial, F(4.12, 234.9) = 227.85, P < 0.001, η2 = 0.46, but no condition by trial interaction, F(4.63, 264.08) = 1.022, P = 0.40, η2 = 0.002. Conclusion: Retrospective memory was greater after closed-skilled exercise (treadmill) when compared to open-skilled exercise (racquetball).

Random Forest Classification of Alcohol Use Disorder Using EEG Source Functional Connectivity, Neuropsychological Functioning, and Impulsivity Measures

: Individuals with alcohol use disorder (AUD) manifest a variety of impairments that can be attributed to alterations in specific brain networks. The current study aims to identify features of EEG-based functional connectivity, neuropsychological performance, and impulsivity that can classify individuals with AUD (N = 30) from unaffected controls (CTL, N = 30) using random forest classification. The features included were: (i) EEG source functional connectivity (FC) of the default mode network (DMN) derived using eLORETA algorithm, (ii) neuropsychological scores from the Tower of London test (TOLT) and the visual span test (VST), and (iii) impulsivity factors from the Barratt impulsiveness scale (BIS). The random forest model achieved a classification accuracy of 80% and identified 29 FC connections (among 66 connections per frequency band), 3 neuropsychological variables from VST (total number of correctly performed trials in forward and backward sequences and average time for correct trials in forward sequence) and all four impulsivity scores (motor, non-planning, attentional, and total) as significantly contributing to classifying individuals as either AUD or CTL. Although there was a significant age difference between the groups, most of the top variables that contributed to the classification were not significantly correlated with age. The AUD group showed a predominant pattern of hyperconnectivity among 25 of 29 significant connections, indicating aberrant network functioning during resting state suggestive of neural hyperexcitability and impulsivity. Further, parahippocampal hyperconnectivity with other DMN regions was identified as a major hub region dysregulated in AUD (13 connections overall), possibly due to neural damage from chronic drinking, which may give rise to cognitive impairments, including memory deficits and blackouts. Furthermore, hypoconnectivity observed in four connections (prefrontal nodes connecting posterior right-hemispheric regions) may indicate a weaker or fractured prefrontal connectivity with other regions, which may be related to impaired higher cognitive functions. The AUD group also showed poorer memory performance on the VST task and increased impulsivity in all factors compared to controls. Features from all three domains had significant associations with one another. These results indicate that dysregulated neural connectivity across the DMN regions, especially relating to hyperconnected parahippocampal hub as well as hypoconnected prefrontal hub, may potentially represent neurophysiological biomarkers of AUD, while poor visual memory performance and heightened impulsivity may serve as cognitive-behavioral indices of AUD.

Cognitive impairment severity in relation to signs of subclinical Wernicke's encephalopathy in HIV and alcoholism comorbidity

OBJECTIVES

The comorbidity of HIV infection and alcoholism (ALC) is prevalent. Wernicke's encephalopathy, a neurological disorder resulting from thiamine depletion, has been generally associated with alcoholism but has also been reported in HIV infection. This study examined whether subclinical Wernicke's encephalopathy signs could contribute to the heterogeneity of cognitive and motor deficits observed in individuals with both disease conditions (HIV+ALC).

DESIGN

Sixty-one HIV+ALC individuals and 59 controls were assessed on attention and working memory, production, immediate and delayed episodic memory, visuospatial abilities, and upper limb motor function.

METHODS

Using Caine criteria (dietary deficiency, oculomotor abnormality, cerebellar dysfunction, and altered mental state), HIV+ALC individuals were classified by subclinical Wernicke's encephalopathy risk factors.

RESULTS

Signs of subclinical Wernicke's encephalopathy were present in 20% of the HIV+ALC participants. For attention/working memory, delayed memory, and upper limb motor function, HIV+ALC Caine 2+ (i.e. meeting two or three criteria) demonstrated the most severe deficits, scoring lower than HIV+ALC Caine 1 (i.e. meeting one criterion), HIV+ALC Caine 0 (i.e. meeting no criteria), and controls.

CONCLUSION

The high prevalence of subclinical signs of Wernicke's encephalopathy and relevance to performance indicate that this condition should be considered in assessment of HIV-infected individuals, especially when alcoholism comorbidity is known or suspected. Above and beyond clinical factors, such as depression, alcoholism and HIV disease-related variables, AIDS, hepatitis C and drug history known to mediate neuropsychological performance, subclinical Wernicke's encephalopathy signs could partly explain the heterogeneity in patterns and severity of cognitive and motor impairments in HIV-infected individuals with alcoholism comorbidity.

Random Forest Classification of Alcohol Use Disorder Using fMRI Functional Connectivity, Neuropsychological Functioning, and Impulsivity Measures

Individuals with alcohol use disorder (AUD) are known to manifest a variety of neurocognitive impairments that can be attributed to alterations in specific brain networks. The current study aims to identify specific features of brain connectivity, neuropsychological performance, and impulsivity traits that can classify adult males with AUD (n = 30) from healthy controls (CTL, n = 30) using the Random Forest (RF) classification method. The predictor variables were: (i) fMRI-based within-network functional connectivity (FC) of the Default Mode Network (DMN), (ii) neuropsychological scores from the Tower of London Test (TOLT), and the Visual Span Test (VST), and (iii) impulsivity factors from the Barratt Impulsiveness Scale (BIS). The RF model, with a classification accuracy of 76.67%, identified fourteen DMN connections, two neuropsychological variables (memory span and total correct scores of the forward condition of the VST), and all impulsivity factors as significantly important for classifying participants into either the AUD or CTL group. Specifically, the AUD group manifested hyperconnectivity across the bilateral anterior cingulate cortex and the prefrontal cortex as well as between the bilateral posterior cingulate cortex and the left inferior parietal lobule, while showing hypoconnectivity in long-range anterior-posterior and interhemispheric long-range connections. Individuals with AUD also showed poorer memory performance and increased impulsivity compared to CTL individuals. Furthermore, there were significant associations among FC, impulsivity, neuropsychological performance, and AUD status. These results confirm the previous findings that alterations in specific brain networks coupled with poor neuropsychological functioning and heightened impulsivity may characterize individuals with AUD, who can be efficiently identified using classification algorithms such as Random Forest.

Randomized trial to assess safety/feasibility of memantine administration during residential treatment for alcohol use disorder: a pilot study

The N-methyl-D-aspartate receptor (NMDAr) system is critically involved in the pathogenesis and neurobehavioral sequelae of alcohol use disorder (AUD), and constitutes a potential pharmacotherapeutic target. Memantine (Namenda) is an FDA-approved NMDAr antagonist with suggested utility in AUD, however its safety and tolerability during long-term administration among recently-detoxified patients remains uncharacterized. This pilot study assessed safety, feasibility, and several secondary measures of interest, during a 4-week period of residential AUD treatment. Participants (N = 18) met diagnostic criteria for AUD. A double-blind, placebo-controlled, escalating-dose design was utilized. Assessments of medication side-effects were conducted weekly. At intake, week 2, and study completion, participants completed a battery assessing affective symptomatology, craving, and neurocognitive function. Medication groups reported equivalent side effects and severity. Medication compliance was high, and did not differ by group. No memantine effects were observed in secondary outcome measures. Memantine maintains a profile of high tolerability and low side-effects during post-detoxification AUD treatment. These data suggest a more aggressive dosing/escalation schedule may be used safely in future trials designed to ascertain improvements in neurocognitive function, affect, and/or craving as primary measures.

Blockade of IL-17 signaling reverses alcohol-induced liver injury and excessive alcohol drinking in mice

Chronic alcohol abuse has a detrimental effect on the brain and liver. There is no effective treatment for these patients, and the mechanism underlying alcohol addiction and consequent alcohol-induced damage of the liver/brain axis remains unresolved. We compared experimental models of alcoholic liver disease (ALD) and alcohol dependence in mice and demonstrated that genetic ablation of IL-17 receptor A (IL-17ra-/-) or pharmacological blockade of IL-17 signaling effectively suppressed the increased voluntary alcohol drinking in alcohol-dependent mice and blocked alcohol-induced hepatocellular and neurological damage. The level of circulating IL-17A positively correlated with the alcohol use in excessive drinkers and was further increased in patients with ALD as compared with healthy individuals. Our data suggest that IL-17A is a common mediator of excessive alcohol consumption and alcohol-induced liver/brain injury, and targeting IL-17A may provide a novel strategy for treatment of alcohol-induced pathology.

Experimental Effects of Acute High-Intensity Resistance Exercise on Episodic Memory Function: Consideration for Post-Exercise Recovery Period

Background

The present experiments evaluated the effects of acute high-intensity resistance exercise on episodic memory.

Methods

Two experiments were conducted. For Experiment 1, participants (N = 40; M_age = 21.0 years) were randomized into one of two groups, including an experimental exercise group and a control group (seated for 20 min). The experimental group engaged in an acute bout of resistance exercises (circuit style exercises) for 15 minutes, followed by a 5-min recovery period. Memory function was subsequently assessed using a multiple trial (immediate and delay), word-list episodic memory task (Rey Auditory Verbal Learning Test, RAVLT), and then followed by a comprehensive, computerized assessment of episodic memory (Treasure Hunt task, THT). The THT involved a spatio-temporal assessment of what, where, and when components of episodic memory. Experiment 2 evaluated if altering the recovery period would influence the potential negative effects of high-intensity resistance exercise on episodic memory function. For Experiment 2, participants (N = 51) were randomized into the same acute resistance exercise protocol but either with a 10-min recovery period, 20-min recovery period, or a control group.

Results

For Experiment 1, for RAVLT, the exercise group performed worse (F_{group × time} = 3.7, p = .001, η ²p = .09). Across nearly all THT outcomes, the exercise group had worse spatio-temporal memory than the control group. These results suggest that high-intensity resistance exercise (with a 5-min recovery) may have a detrimental effect on episodic memory function. For Experiment 2, for RAVLT, the exercise with 10-min recovery group performed better (F_{group × time} = 3.1, p = .04, η ²p = .11). Unlike Experiment 1, exercise did not impair spatio-temporal memory, with the 20-min exercise recovery group having the best "where" component of episodic memory.

Conclusion

Collectively, the results from these two experiments suggest that acute high-intensity resistance exercise may impair episodic memory when a short exercise recovery period (e.g., 5-min) is employed, but with a longer recovery period (10+ min), acute high-intensity resistance exercise may, potentially, enhance episodic memory.

Emotional Face Processing among Treatment-Seeking Individuals with Alcohol Use Disorders: Investigating Sex Differences and Relationships with Interpersonal Functioning

BACKGROUND

Individuals in treatment for alcohol use disorder (AUD) display deficits across a broad range of cognitive processes. Disruptions in affective processing are understudied, but may be particularly important for interpersonal functioning and post-treatment adaptation. In particular, the role of sex in AUD-associated emotion processing deficits remains largely unaddressed and was a focus of the current investigation.

METHODS

Fifty-six treatment seekers with AUD and 54 healthy community controls (N = 110) were administered an emotional face discrimination task. Non-affective tasks included a sex-discrimination task and two brief measures of executive functioning. Two measures of interpersonal function were included.

RESULTS

Emotion processing deficits were evident among women with AUD relative to other groups. This sex-contingent relationship was not observed in measures of executive function, sex-discrimination or interpersonal problems, although individuals with AUD performed more poorly on these measures.

CONCLUSIONS

Results were consistent with extant literatures examining cognitive, affective and interpersonal functioning among individuals with AUD, and provided novel evidence of vulnerability to alcohol-associated deficits in emotion processing among women. While similar sex-contingent effects were not apparent among other measures, results support modest interrelationships, specifically including the import of emotion processing to interpersonal functioning in AUD. These data offer guidance for further systematic investigation and highlight important considerations for future relapse-prevention and recovery-facilitation efforts.