Executive dysfunction in substance dependent individuals during drug use and abstinence: an examination of the behavioral, cognitive and emotional correlates of addiction

Neurocognitive function and medical care utilization in Veterans treated for substance use disorder

BACKGROUND

Veterans with substance use disorder (SUD) are at high risk for cognitive problems due to neurotoxic effects of chronic drug and alcohol use coupled in many cases with histories of traumatic brain injury (TBI). These problems may in turn result in proneness to SUD relapse and reduced adherence to medical self-care regimens and therefore reliance on health care systems. However, the direct relationship between cognitive function and utilization of Veterans Health Administration (VHA) SUD and other VHA health care services has not been evaluated. We sought initial evidence as to whether neurocognitive performance relates to repeated health care engagement in Veterans as indexed by estimated VHA care costs.

METHODS

Neurocognitive performance in 76 Veterans being treated for SUD was assessed using CNS-Vital Signs, a commercial computerized cognitive testing battery, and related to histories of outpatient and inpatient/residential care costs as estimated by the VHA Health Economics Resource Center.

RESULTS

After controlling for age, an aggregate metric of overall neurocognitive performance (Neurocognition Index) correlated negatively with total VHA health care costs, particularly with SUD-related outpatient care costs but also with non-mental health-related care costs. Barratt Impulsiveness Scale scores also correlated positively with total VHA care costs.

CONCLUSIONS

In Veterans receiving SUD care, higher impulsivity and lower cognitive performance were associated with greater health care utilization within the VHA system. This suggests that veterans with SUD who show lower neurocognitive performance are at greater risk for continued health problems that require healthcare engagement. Cognitive rehabilitation programs developed for brain injury and other neurological conditions could be tried in Veterans with SUD to improve their health outcomes.

Executive functions and their relationship with age: Insights from a novel neuropsychological Assessment Battery in Children-a pilot study

Executive functions (EFs) are a set of cognitive processes that enable individuals to manage and coordinate their thoughts and actions toward achieving specific goals. EFs include planning, organizing, initiating, and monitoring actions, and have been found to improve with age due to the maturation of the brain, especially during childhood. Therefore, our correlational study sought to determine the relationship between the performance in executive functions and age in 79 children (36 girls, 45.6%) throughout development, between the ages of 6 and 12 (mean = 9.25; SD = 2.05), using a battery designed in Chile: BEFE (Batería de Evaluación de las Funciones Ejecutivas: Executive Function Assessment Battery) based on traditional neuropsychological tests to evaluate Working Memory, Inhibitory Control, Cognitive Flexibility, and Planning skills. Our results showed various correlations between the variables age and performance in various behavioral parameters, demonstrating an increase in the number of correct responses (positive correlation) and/or a decrease in errors (negative correlation) with age (6-12) in the subtests that correspond to dimensions of Cognitive Flexibility (Semantic and Phonological Fluency, Card Sorting Game, and Tracing Tasks), Inhibitory Control (ENA-F and Sentence Completion), Working Memory (Audio-verbal WM Forward and Ordering, and Visuospatial WM Forward and Backward), and Planning (La Portada de Antofagasta and FISA Maps). These results are consistent with previous empirical evidence and support the notion of a developmental relationship between EF performance and age. Additionally, this study contributes to understanding EF development in culturally specific contexts, highlighting the importance of contextually relevant assessment tools in evaluating cognitive development.

Linking haploinsufficiency of the autism- and schizophrenia-associated gene Cyfip1 with striatal-limbic-cortical network dysfunction and cognitive inflexibility

Impaired behavioural flexibility is a core feature of neuropsychiatric disorders and is associated with underlying dysfunction of fronto-striatal circuitry. Reduced dosage of Cyfip1 is a risk factor for neuropsychiatric disorder, as evidenced by its involvement in the 15q11.2 (BP1-BP2) copy number variant: deletion carriers are haploinsufficient for CYFIP1 and exhibit a two- to four-fold increased risk of schizophrenia, autism and/or intellectual disability. Here, we model the contributions of Cyfip1 to behavioural flexibility and related fronto-striatal neural network function using a recently developed haploinsufficient, heterozygous knockout rat line. Using multi-site local field potential (LFP) recordings during resting state, we show that Cyfip1 heterozygous rats (Cyfip1+/-) harbor disrupted network activity spanning medial prefrontal cortex, hippocampal CA1 and ventral striatum. In particular, Cyfip1+/- rats showed reduced influence of nucleus accumbens and increased dominance of prefrontal and hippocampal inputs, compared to wildtype controls. Adult Cyfip1+/- rats were able to learn a single cue-response association, yet unable to learn a conditional discrimination task that engages fronto-striatal interactions during flexible pairing of different levers and cue combinations. Together, these results implicate Cyfip1 in development or maintenance of cortico-limbic-striatal network integrity, further supporting the hypothesis that alterations in this circuitry contribute to behavioural inflexibility observed in neuropsychiatric diseases including schizophrenia and autism.

The test-retest reliability of the Opiate Treatment Index in nyaope users in Johannesburg

Background

Epidemiological studies suggest that nyaope, a heroin-based drug, is widely used in South Africa. Yet few reliable research tools are available to assess treatment outcomes of users. The Opiate Treatment Index (OTI), a tool developed in Australia, could potentially facilitate research on context-specific South African treatment outcomes. However, we know little of its test-retest reliability.

Aim

This study aimed to assess the test-retest reliability of the OTI among a sample of nyaope users in Johannesburg.

Setting

This study was conducted across three substance use treatment facilities in Johannesburg.

Methods

The OTI was administered to 53 nyaope users at baseline and one week later. To determine the test-retest reliability of the OTI, the intra-class correlation coefficients (ICC) and the Brennan-Prediger coefficients of the two interviews were calculated.

Results

The ICC of the Q-scores from the data sets along with the Brennan-Prediger coefficient for the substance use domain were calculated. The ICC for nyaope was 0.38. Brennan-Prediger coefficients were as follows: alcohol - 0.96, crack-cocaine - 0.89, cannabis - 0.92, methaqualone - 0.85 and crystal methamphetamine - 0.89.

Conclusion

A significant positive finding was the excellent test-retest reliability of the injecting and sexual behaviour domains and moderate reliability of the criminality, general health and social functioning domains.

Contribution

The results of this study provide insight into the reliability of this tool and for its use in future studies in the South African context.

Morphine exposure modulates dimensional bias and set formation in anthropoids

Humans demonstrate significant behavioural advantages with particular perceptual dimensions (such as colour or shape) and when the relevant dimension is repeated in consecutive trials. These dimension-related behavioural modulations are significantly altered in neuropsychological and addiction disorders; however, their underlying mechanisms remain unclear. Here, we studied whether these behavioural modulations exist in other trichromatic primate species and whether repeated exposure to opioids influences them. In a target detection task where the target-defining dimension (colour or shape) changed trial by trial, humans exhibited shorter response time (RT) and smaller event-related electrodermal activity with colour dimension; however, macaque monkeys had shorter RT with shape dimension. Although the dimensional biases were in the opposite directions, both species were faster when the relevant dimension was repeated, compared with conditions when it changed, across consecutive trials. These indicate that both species formed dimensional sets and that resulted in a significant 'switch cost'. Scheduled and repeated exposures to morphine, which is analogous to its clinical and recreational use, significantly augmented the dimensional bias in monkeys and also changed the switch cost depending on the relevant dimension. These cognitive effects occurred when monkeys were in abstinence periods (not under acute morphine effects) but expressing significant morphine-induced conditioned place preference. These findings indicate that significant dimensional biases and set formation are evolutionarily preserved in humans' and monkeys' cognition and that repeated exposure to morphine interacts with their manifestation. Shared neural mechanisms might be involved in the long-lasting effects of morphine and expression of dimensional biases and set formation in anthropoids.

Effects of Aerobic Exercise Combined With Attentional Bias Modification in the Care of Male Patients With a Methamphetamine Use Disorder

OBJECTIVE

It remains unclear which individual or combined strategies are most beneficial for methamphetamine use disorders (MUDs). We compared the effects of aerobic exercise, attentional bias modification, and combined intervention on male patients with MUD.

METHOD

One hundred male patients with MUD were randomly assigned to combined intervention, aerobic exercise, attentional bias modification, or control groups (25 patients per group). The 8-week intervention protocol included three 60-minute sessions of aerobic exercises per week. Primary outcomes included high- and low-frequency heart rate variability, executive function, and cardiorespiratory fitness measured by customized software, computerized tests, and the Harvard step test, respectively. Secondary outcomes included psychiatric symptoms, drug craving, training acceptability, and persistence.

RESULTS

Participant characteristics were matched between groups at baseline. Executive function, heart rate variability, cardiorespiratory fitness, drug craving, and most psychiatric symptoms had significant time-group interactions at posttest (p < .05, η2 = .08-.28). Compared with the attentional bias modification and control groups, the combined intervention and aerobic exercise groups improved significantly in executive function, heart rate variability, cardiorespiratory fitness, and most secondary outcomes. In addition, high-frequency heart rate variability and cardiorespiratory fitness in the aerobic exercise group were significantly higher than those in the combined intervention group.

CONCLUSIONS

Combination strategies showed comparable efficacy to aerobic exercise alone in improving executive function, psychiatric symptoms, and drug craving and significantly exceeded other conditions. For heart rate variability and cardiorespiratory fitness, aerobic exercise alone was the most effective. For acceptability and persistence, combination strategies were preferred over single-domain training and health education intervention.

The effect of mindfulness on decision-making, inhibitory control, and impulsivity of substance use disorder in-treatment patients: A randomized clinical trial

This study aimed to investigate the effects of Mindfulness-Based Relapse Prevention (MBRP) in decision-making, inhibitory control and impulsivity compared to Treatment as Usual (TAU) for individuals with Substance Use Disorders (SUD's) in Brazil. A randomized clinical trial was conducted with participants from a therapeutic community (n = 122). Decision-making (Iowa Gambling Task), impulsivity dimensions (UPPS-P Scale), and inhibitory control (Stroop Color-Word Test) were assessed before and after the MBRP 8-week intervention. GLM Multivariate analysis was used to evaluate the effects of MBRP on different impulsivity measures. The results showed that MBRP+TAU improved the general decision-making score (p = 0,008) compared to TAU. However, no significant effects were found in impulsivity dimensions and inhibitory control in individuals with SUDs in the therapeutic community. This study found improvement in decision-making in the total IGT score; however, no effect for self-reported impulsivity and inhibitory control among middle-aged patients after an 8-weeks intervention of MBRP protocol in an inpatient setting. It adds information to the subject, with implications and possible directions to be followed by the next clinical trials with patients with SUDs in treatment. Trial registration: EnsaiosClinicos.gov.br: RBR-6c9njc.

Dysregulated Emotion and Trying Substances in Childhood: Insights from a Large Nationally Representative Cohort Study

OBJECTIVE

Transdiagnostic perspectives on the shared origins of mental illness posit that dysregulated emotion may represent a key driving force behind multiple forms of psychopathology, including substance use disorders. The present study examined whether a link between dysregulated emotion and trying illicit substances could be observed in childhood.

METHOD

In a large (N = 7,418) nationally representative sample of children (Mage = 9.9), individual differences in emotion dysregulation were indexed using child and parent reports of frequency of children's emotional outbursts, as well as children's performance on the emotional N-Back task. Two latent variables, derived from either parental/child-report or performance-based indicators, were evaluated as predictors of having ever tried alcohol, tobacco, or marijuana.

RESULTS

Results showed that reports of dysregulated emotion were linked to a greater likelihood of trying both alcohol and tobacco products. These findings were also present when controlling for individual differences in executive control and socioeconomic status.

CONCLUSIONS

These results suggest that well-established links between dysregulated negative emotion and substance use may emerge as early as in childhood and also suggest that children who experience excessive episodes of uncontrollable negative emotion may be at greater risk for trying substances early in life.

Emotional Expression on Social Media Support Forums for Substance Cessation: Observational Study of Text-Based Reddit Posts

BACKGROUND

Substance use disorder is characterized by distinct cognitive processes involved in emotion regulation as well as unique emotional experiences related to the relapsing cycle of drug use and recovery. Web-based communities and the posts they generate represent an unprecedented resource for studying subjective emotional experiences, capturing population types and sizes not typically available in the laboratory. Here, we mined text data from Reddit, a social media website that hosts discussions from pseudonymous users on specific topic forums, including forums for individuals who are trying to abstain from using drugs, to explore the putative specificity of the emotional experience of substance cessation.

OBJECTIVE

An important motivation for this study was to investigate transdiagnostic clues that could ultimately be used for mental health outreach. Specifically, we aimed to characterize the emotions associated with cessation of 3 major substances and compare them to emotional experiences reported in nonsubstance cessation posts, including on forums related to psychiatric conditions of high comorbidity with addiction.

METHODS

Raw text from 2 million posts made, respectively, in the fall of 2020 (discovery data set) and fall of 2019 (replication data set) were obtained from 394 forums hosted by Reddit through the application programming interface. We quantified emotion word frequencies in 3 substance cessation forums for alcohol, nicotine, and cannabis topic categories and performed comparisons with general forums. Emotion word frequencies were classified into distinct categories and represented as a multidimensional emotion vector for each forum. We further quantified the degree of emotional resemblance between different forums by computing cosine similarity on these vectorized representations. For substance cessation posts with self-reported time since last use, we explored changes in the use of emotion words as a function of abstinence duration.

RESULTS

Compared to posts from general forums, substance cessation posts showed more expressions of anxiety, disgust, pride, and gratitude words. "Anxiety" emotion words were attenuated for abstinence durations >100 days compared to shorter durations (t12=3.08, 2-tailed; P=.001). The cosine similarity analysis identified an emotion profile preferentially expressed in the cessation posts across substances, with lesser but still prominent similarities to posts about social anxiety and attention-deficit/hyperactivity disorder. These results were replicated in the 2019 (pre-COVID-19) data and were distinct from control analyses using nonemotion words.

CONCLUSIONS

We identified a unique subjective experience phenotype of emotions associated with the cessation of 3 major substances, replicable across 2 time periods, with changes as a function of abstinence duration. Although to a lesser extent, this phenotype also quantifiably resembled the emotion phenomenology of other relevant subjective experiences (social anxiety and attention-deficit/hyperactivity disorder). Taken together, these transdiagnostic results suggest a novel approach for the future identification of at-risk populations, allowing for the development and deployment of specific and timely interventions.

Effects of exercise on cognitive functioning in adults with serious mental illness: A meta analytic review

Cognitive performance is usually impaired in those with serious mental illness (SMI). Exercise may improve cognitive functioning, but studies examining the effects of exercise in SMI indicate heterogenous findings. To estimate the effects of exercise on cognitive outcomes in people with SMI. Randomized controlled trials evaluating the acute or chronic effects of exercise on cognitive functioning in SMI were searched from inception to December 26th, 2022 on major electronic databases. Random effect meta-analyses were conducted to assess the effects of exercise on over the cognitive domains and Standardized Mean Differences (SMD) and 95% confidence intervals (CIs) were used as the effect size measure. Funnel plots and Egger's test of effect size and the Trim and Fill procedure applied if evidence of publication bias was noted. Methodological quality was assessed using RoB 2. A total of 15 chronic (1 acute), 936 participants (46.7% women). Exercise showed large effects on reasoning and problem solving; small effects on executive functioning. Per diagnosis, exercise showed moderate positive effects on executive functioning and large effects on processing speed in people with depression; large effects on reasoning and problem solving in people with schizophrenia. The present study indicates a large beneficial effect of chronic physical exercise on reasoning and problem solving and small effects on executive functioning in people with SMI.

Nurses' Psychological Trauma and Cognitive Control in the COVID-19 Pandemic

Introduction

During the COVID-19 pandemic, nurses have faced various nurse-specific traumas in their workplaces, but there is limited understanding of the resulting outcomes and factors that contribute to them.

Objective

To address this gap, the study employed the middle-range theory of nurses' psychological trauma (NPT) to examine these relationships among frontline nurses working in critical care areas.

Methods

In a quantitative cross-sectional study, the study compared nurses identified as probable cases of posttraumatic stress disorder (PTSD) with those identified as not probable cases. The study investigated the nurse-specific traumas they experienced, their individual personality traits, and the buffers they possessed. The study also sought to identify specific types of nurse-specific traumas that could be associated with negative outcomes, such as alcohol and drug use.

Results

It was found that PTSD-probable nurses reported higher levels of trauma from disasters and system/medically induced trauma compared to not-probable nurses. They also experienced more nonwork-related humankind traumas and displayed lower resilience. Furthermore, PTSD-probable nurses identified with trait urgency and trait avoidance motivation. Additionally, trauma from disasters was associated with alcohol use.

Conclusion

The study highlights the elevated levels of trauma, lower resilience, and specific psychological traits associated with PTSD-probable nurses, emphasizing the need for targeted interventions and support to mitigate the negative outcomes experienced by frontline nurses.

The effect of high-intensity interval training on cognitive function in patients with substance use disorder: Study protocol for a two-armed randomized controlled trial

Introduction

Substance use disorder (SUD) is characterized by cognitive impairment, especially executive dysfunction. Executive function is recognized as an important determinant of treatment outcome as it is associated with dropout rate, attendance to therapy and potential relapse after treatment termination. Physical activity can have beneficial effects on cognitive function, but there is still a lack of knowledge regarding potential benefits of aerobic exercise for executive function in SUD treatment. The aim of this study is to examine the effect of aerobic high-intensity interval training (HIIT) on cognitive function and the subsequent effect on treatment outcome in patients with SUD.

Methods and analysis

This study is a randomized controlled trial, including men and women ≥18 years with diagnosed SUD by ICD-10. The patients will be recruited from the department for inpatient treatment at Blue Cross - Lade Addiction Treatment Center, Trondheim, Norway. Participants will be randomized 1:1 into either HIIT (3x/week) + treatment as usual (TAU), or TAU alone. Study outcomes will be assessed at baseline, after eight weeks of intervention, and at 3- and 12-months follow-up. The primary outcome is to compare the change in executive function (via altered BRIEF-A score, Behavior Rating Inventory of Executive Function-Adult) measured between the two study groups after eight weeks. Secondary outcomes include mapping of cognitive function in different subgroups (e.g. type of substance, age, fitness level), collecting self-reported information about quality of life, craving, sleep quality, etc., as well as assessing compliance to TAU and long-term treatment outcome.

Ethics and dissemination

The project was approved by the Regional Ethical Committee and will be performed in accordance with this protocol and the Declaration of Helsinki. Written informed consent will be obtained from all participants prior to inclusion. This project will explore a novel approach to how exercise can be applied in SUD treatment, beyond the well-known effects on physical health. We expect to achieve new knowledge in regard to what extent HIIT can improve cognitive abilities and subsequent treatment outcome in SUD.

Trial registration number

https://www.clinicaltrials.gov/NCT05324085.

Noradrenergic circuits and signaling in substance use disorders

The central noradrenergic system innervates almost all regions of the brain and, as such, is well positioned to modulate many neural circuits implicated in behaviors and physiology underlying substance use disorders. Ample pharmacological evidence demonstrates that α1, α2, and β adrenergic receptors may serve as therapeutic targets to reduce drug -seeking behavior and drug withdrawal symptoms. Further, norepinephrine is a key modulator of the stress response, and stress has been heavily implicated in reinstatement of drug taking. In this review, we discuss recent advances in our understanding of noradrenergic circuitry and noradrenergic receptor signaling in the context of opioid, alcohol, and psychostimulant use disorders.

Mental Health Symptoms Associated with Sexualized Drug Use (Chemsex) among Men Who Have Sex with Men: A Systematic Review

Background: Sexualized drug use (SDU), also known as chemsex, refers to the use of psychoactive substances for sexual purposes among men who have sex with men (MSM), which has been associated with mental health symptoms. The objective of this review is to systematically review the available evidence on mental health outcomes in MSM who use sexualized drugs. Methods: To prepare this systematic review, search strategies were developed and applied to the Web of Science, Science Direct, PubMed, and Scopus databases. A total of 117 articles were found, of which 12 were selected for the final review. Results: Those MSM who practiced SDU were more likely to experience from depression, anxiety, or a substance dependence, although these results were not found in all the studies analyzed. Among those who practiced the administration of intravenous drugs (referred to as slamsex), the mental health symptoms were more severe. Conclusions: This systematic review contributes to a fuller understanding of the mental health symptoms present in MSM who consume drugs for sexual purposes. Greater uniformity in data collection instruments is required, as well as the need to conduct a more in-depth assessment of the psychosocial adjustment of people who practice chemsex.

Substance use disorder and obesogenic eating: Does working memory training strengthen ability to abstain from unwanted behaviors? A systematic review

INTRODUCTION

Abstaining from unwanted behaviors requires a sufficient balance between the executive and impulsive cognitive systems. Working memory (WM) is a vital component of both systems, identified in a wide range of research as the central and dominant component of executive function. WM potentially modulates the desires, tendencies, and behaviors specific to and seen in individuals with substance use disorder (SUD) and obesogenic eating (OE). Compared to healthy populations, research has shown individuals with SUD, as well as those who display OE, to have some degree of executive dysfunction, and both conditions have far-reaching health care implications. Additionally, these deficits are associated with impulsive behavior. Research has proposed that impulsive and so-called reward-driven responses could be altered through cognitive therapy and that both SUD and OE could benefit from working memory training (WMT).

METHOD

In this narrative review, we systematically align extant empirical reasoning and evidence with these assumptions. Our main aim is to ascertain and summarize the value of WMT for the treatment of both SUD and food reward consummatory behaviors. As a means to include detailed narrative accounts of all papers of potential value, our thresholds for meaningful improvements in both WM and unwanted behaviors are broad.

RESULTS

The results from the eleven qualifying studies are as follows: Nine of ten studies show a significant positive training effect of WMT on one or more components of WM capacity; three of six eligible papers (two on alcohol and one on opioid addiction) deliver notable improvements in SUD in response to WMT. One of two suitable studies showed WMT to be a moderately efficacious form of therapy for OE. Conversely, WMT appears to have negligible therapeutic benefit for cognitive function deficits or psychopathology unrelated to WM, suggesting that WMT has unique treatment efficacy for impulsive human behaviors.

CONCLUSION

In conclusion, more rigorous and uniform studies on WMT and impulsive harmful behaviors are required to give proof of the benefits of this potential useful treatment.

Effect of aerobic exercise on executive function in individuals with methamphetamine use disorder: Modulation by the autonomic nervous system

This study assessed the effects of aerobic exercise on cardiac autonomic nervous system function (based on heart rate variability [HRV]) and executive function among individuals with methamphetamine use disorder (MUD). We further examine the role of autonomic nervous system control in aerobic exercise (assessed via cardiopulmonary fitness) and executive function. A total of 330 individuals with MUD were randomly divided into exercise (n = 165) and control (n = 165) groups, who underwent eight-week aerobic exercise/health education program consisting of five 60 min sessions a week. The outcome measures included cardiopulmonary fitness, HRV time-domain and frequency-domain parameters, and executive function. Our statistical analyses comprised repeated-measures analyses of variance, correlation analyses, and mediation and moderation effect tests. The results indicated that aerobic exercise could simultaneously improve autonomic nervous system function and executive function among individuals with MUD. Moreover, the changes in cardiopulmonary fitness, high frequency HRV, and executive function were positively correlated. HRV did not significantly mediate the relationship between aerobic exercise and executive function; however, it did have a moderating effect, which was eliminated after adjusting for demographic and drug-use covariates. Among the covariates, age was the greatest confounder and was inversely proportional to cardiopulmonary function, HRV, and executive function. Cardiac autonomic nervous system function exerted a moderating, rather than a mediating, effect on the relationship between aerobic exercise and executive function. However, this potential effect was largely influenced by covariates, particularly age.

Neuropsychological Functioning in Users of Serotonergic Psychedelics - A Systematic Review and Meta-Analysis

Background: Serotonergic psychedelics (SPs) like LSD, psilocybin, DMT, and mescaline are a heterogeneous group of substances that share agonism at 5-HT2a receptors. Besides the ability of these substances to facilitate profoundly altered states of consciousness, persisting psychological effects have been reported after single administrations, which outlast the acute psychedelic effects. In this review and meta-analysis, we investigated if repeated SP use associates with a characteristic neuropsychological profile indicating persisting effects on neuropsychological function. Methods: We conducted a systematic review of studies investigating the neuropsychological performance in SP users, searching studies in Medline, Web of Science, embase, ClinicalTrials.gov, and EudraCT. Studies were included if they reported at least one neuropsychological measurement in users of SPs. Studies comparing SP users and non-users that reported mean scores and standard deviations were included in an exploratory meta-analysis. Results: 13 studies (N = 539) published between 1969 and 2020 were included in this systematic review. Overall, we found that only three SPs were specifically investigated: ayahuasca (6 studies, n = 343), LSD (5 studies, n = 135), and peyote (1 study, n = 61). However, heterogeneity of the methodological quality was high across studies, with matching problems representing the most important limitation. Across all SPs, no uniform pattern of neuropsychological impairment was identified. Rather, the individual SPs seemed to be associated with distinct neuropsychological profiles. For instance, one study (n = 42) found LSD users to perform worse in trials A and B of the Trail-Making task, whereas meta-analytic assessment (5 studies, n = 352) of eleven individual neuropsychological measures indicated a better performance of ayahuasca users in the Stroop incongruent task (p = 0.03) and no differences in the others (all p > 0.05). Conclusion: The majority of the included studies were not completely successful in controlling for confounders such as differences in non-psychedelic substance use between SP-users and non-users. Our analysis suggests that LSD, ayahuasca and peyote may have different neuropsychological consequences associated with their use. While LSD users showed reduced executive functioning and peyote users showed no differences across domains, there is some evidence that ayahuasca use is associated with increased executive functioning.

Executive functions and emotion regulation in substance use disorder

ABSTRACT Objective The executive functions (EF) and emotion regulation (ER) and their relationship with the substance use disorder (SUD) were analyzed. Methods A cross-sectional design was used. The sample consisted of 130 volunteers divided into three groups: group 01 (n = 60), composed of participants who did not meet the diagnostic criteria for any type of SUD; group 02 (n = 51), with users with alcohol and/or tobacco use disorder; group 03 (n = 19), with users with multiple substance use disorder, including at least one illicit substance. Results Group 02 presented worse performance in EF and ER when compared to group 01, and showed a significant correlation between the working memory and the use of maladaptive ER. Group 03 showed great losses in EF and ER when compared to the other groups. Conclusion This study supports the idea that EF, ER and SUD are related. In addition, it was observed that people with SUD had worse performance in EF and ER when compared to people without SUD, greater damage being observed in people with SUD of polysubstances.

The role of repetitive transcranial magnetic stimulation (rTMS) in the treatment of behavioral addictions: Two case reports and review of the literature

BACKGROUND

Several behaviors, besides consumption of psychoactive substances, produce short-term reward that may lead to persistent aberrant behavior despite adverse consequences. Growing evidence suggests that these behaviors warrant consideration as nonsubstance or "behavioral" addictions, such as pathological gambling, internet gaming disorder and internet addiction.

CASE PRESENTATION

Here, we report two cases of behavioral addictions (BA), compulsive sexual behavior disorder for online porn use and internet gaming disorder. A 57-years-old male referred a loss of control over his online pornography use, started 15 years before, while a 21-years-old male university student reported an excessive online gaming activity undermining his academic productivity and social life. Both patients underwent a high-frequency repetitive transcranial magnetic stimulation (rTMS) protocol over the left dorsolateral prefrontal cortex (l-DLPFC) in a multidisciplinary therapeutic setting. A decrease of addictive symptoms and an improvement of executive control were observed in both cases.

DISCUSSION

Starting from these clinical observations, we provide a systematic review of the literature suggesting that BAs share similar neurobiological mechanisms to those underlying substance use disorders (SUD). Moreover, we discuss whether neurocircuit-based interventions, such as rTMS, might represent a potential effective treatment for BAs.

Effect of Abstinence on Psychological Distress Scores, Social Dysfunction Scores, Total General Health Questionnaire Scores-12, and Total Quality of Life Scores in Men with Methamphetamine Dependence in Therapeutic Community

AIM: We looked for differences in abstinence influence on Psychological Distress Scores, Social Dysfunction Scores, Total General Health Questionnaire – 12 (GHQ-12), and Total Quality of Life Scores on men with Methamphetamine dependence in the Therapeutic Community. METHODS: This study was conducted a numerical comparative analytical analysis paired with twice measurements with subject retrieval done using consecutive sampling. The participant of this study was 47 subjects who selected by inclusion and exclusion criteria. RESULTS: Found psychological distress score of the abuser was p ˂ 0.001, different with social dysfunction score there was no significant difference where the score was p = 0.062, the total GHQ-12 score was a significant difference where the score was p = 0.025 while in the total quality of life score (SF-36) there was a significant difference with the score of p ˂ 0.001. CONCLUSIONS: After abstinence, quarantine was found to improve attitude, behavior, cognitive, and social function such as appropriate communication and active social relationship with others compared with before abstinence quarantine.

Behavioral, Emotional and Social Apathy in Alcohol-Related Cognitive Disorders

Apathy is a fundamental neuropsychiatric symptom of Korsakoff's syndrome (KS) and has also been reported in patients with alcohol use disorder with no (AUD) or less severe cognitive impairments (ARCI). However, research on the nature of apathy is limited in these groups. Aim of this study was to examine the multidimensional nature of apathy in patients with KS, ARCI and AUD. Moreover, we examined differences between apathy ratings by patients and their professional caregivers, and related apathy to everyday functioning and overall cognition. Twenty-five patients with KS, 25 patients with ARCI and 23 patients with AUD participated in this study. Apathy was measured using the apathy motivation index (AMI), which distinguishes behavioral, emotional and social apathy. Both patients and professional caregivers reported social apathy as the most prominent symptom, compared to behavioral and emotional apathy. Apathy ratings did not differ across the three patient groups. Discrepancies between patient and caregiver ratings were observed in patients with KS and ARCI, with more severe apathy reported by caregivers. Caregiver-reported behavioral and social, but not emotional, apathy was related to everyday functioning. These results show that apathy is present in a substantial proportion of patients with alcohol addiction with or without cognitive impairments.

Cognition and Pain: A Review

Cognition is defined as the brain's ability to acquire, process, store, and retrieve information. Pain has been described as an unpleasant sensory or emotional experience, and for experiencing pain consciously, cognitive processing becomes imperative. Moreover, evaluation of pain strongly depends on cognition as it requires learning and recall of previous experiences. There could be a possible close link between neural systems involved in cognition and pain processing, and studies have reported an association between pain and cognitive impairment. In this narrative review, we explore the available evidence that has investigated cognitive changes associated with pain. We also examine the anatomical, biochemical, and molecular association of pain and neuro-cognition. Additionally, we focus on the cognitive impairment caused by analgesic medications. There is a need to improve our understanding of pathophysiology and cognitive impairment mechanisms associated with chronic pain and its treatment. This area provides a diverse opportunity for grounding future research, aiding institution of timely interventions to prevent chronic pain and associated cognitive decline, ultimately improving patient care.

Ethanol inhibition of lateral orbitofrontal cortex neuron excitability is mediated via dopamine D1/D5 receptor-induced release of astrocytic glycine

Recent findings from this laboratory demonstrate that ethanol reduces the intrinsic excitability of orbitofrontal cortex (OFC) neurons via activation of strychnine-sensitive glycine receptors. Although the mechanism linking ethanol to the release of glycine is currently unknown, astrocytes are a source of neurotransmitters including glycine and activation of dopamine D1-like receptors has been reported to enhance extracellular levels of glycine via a functional reversal of the astrocytic glycine transporter GlyT1. We recently reported that like ethanol, dopamine or a D1/D5 receptor agonist increases a tonic current in lateral OFC (lOFC) neurons. Therefore, in this study, we used whole-cell patch-clamp electrophysiology to examine whether ethanol inhibition of OFC spiking involves the release of glycine from astrocytes and whether this release is dopamine receptor dependent. Ethanol, applied acutely, decreased spiking of lOFC neurons and this effect was blocked by antagonists of GlyT1, the norepinephrine transporter or D1-like but not D2-like receptors. Ethanol enhanced the tonic current of OFC neurons and occluded the effect of dopamine suggesting that ethanol and dopamine may share a common pathway. Altering astrocyte function by suppressing intracellular astrocytic calcium signaling or blocking the astrocyte-specific Kir4.1 potassium channels reduced but did not completely abolish ethanol inhibition of OFC neuron firing. However, when both astrocytic calcium signaling and Kir4.1 channels were inhibited, ethanol had no effect on firing. Ethanol inhibition was also prevented by inhibitors of phospholipase C and conventional isoforms of protein kinase C (cPKC) previously shown to block D1R-induced GlyT1 reversal and PKC inhibition of Kir4.1 channels. Finally, the membrane potential of OFC astrocytes was depolarized by bath application of a Kir4.1 blocker, a D1 agonist or ethanol and ethanol effect was blocked by a D1 antagonist. Together, these findings suggest that acute ethanol inhibits OFC neuron excitability via a D1 receptor-mediated dysregulation of astrocytic glycine transport.

Neural Modulation in Approach-Avoidance Conflicts in Externalizing Psychopathology

Externalizing psychopathology (EXT) is characterized by poor decision-making in situations that involve simultaneous cues for approach and avoidance behavior (i.e. approach-avoidance conflicts). Previous studies of EXT have examined these deficits primarily using tasks involving decisions between positive reward and negative punishment, suggesting that EXT is characterized by a general bias towards high salience (e.g. temporally proximal or reward) cues relative to low salience (e.g. temporally distal or loss) cues. However, in order to better characterize decision-making in approach-avoidance conflicts, the present study utilized a novel task to examine neural activation in contexts involving both positive reward and negative punishment as well as positive punishment and negative reward by manipulating physical proximity of affective cues. Neuroimaging results indicated that EXT was associated with deficits related to cue prioritization based on salience, suggesting that failure to differentiate relevant from less relevant information contributes to poor decision-making among individuals with EXT.

Single Exposure to Cocaine Impairs Reinforcement Learning by Potentiating the Activity of Neurons in the Direct Striatal Pathway in Mice

Plasticity in the glutamatergic synapses on striatal medium spiny neurons (MSNs) is not only essential for behavioral adaptation but also extremely vulnerable to drugs of abuse. Modulation on these synapses by even a single exposure to an addictive drug may interfere with the plasticity required by behavioral learning and thus produce impairment. In the present work, we found that the negative reinforcement learning, escaping mild foot-shocks by correct nose-poking, was impaired by a single in vivo exposure to 20 mg/kg cocaine 24 h before the learning in mice. Either a single exposure to cocaine or reinforcement learning potentiates the glutamatergic synapses on MSNs expressing the striatal dopamine 1 (D1) receptor (D1-MSNs). However, 24 h after the cocaine exposure, the potentiation required for reinforcement learning was disrupted. Specific manipulation of the activity of striatal D1-MSNs in D1-cre mice demonstrated that activation of these MSNs impaired reinforcement learning in normal D1-cre mice, but inhibition of these neurons reversed the reinforcement learning impairment induced by cocaine. The results suggest that cocaine potentiates the activity of direct pathway neurons in the dorsomedial striatum and this potentiation might disrupt the potentiation produced during and required for reinforcement learning.

Quantitative EEG in Childhood Attention Deficit Hyperactivity Disorder and Learning Disabilities

The clinical use of the quantitative EEG (QEEG) from the pioneering work of John has received a new impetus thanks to new neuroimaging techniques and the possibility of using a number of normative databases both of normal subjects and of subjects with definite pathologies. In this direction, the term personalized medicine is becoming more and more common, a medical procedure that separates patients into different groups based on their predicted response to the quantitative EEG. This has allowed the study of single subjects and to customize health care, with decisions and treatments tailored to each individual patient, as well as improvement of knowledge of the pathophysiological mechanisms of specific diseases. This review article will present the most recent evidence in the field of developmental neuropsychiatric disorders obtained from the application of quantitative EEG both in clinical group studies (attention deficit hyperactivity disorder, developmental dyslexia, oppositional defiant disorder) and in individual case studies not yet published.

Lack of longitudinal changes in cognition in individuals with methamphetamine use disorder during the first 6 weeks after commencing treatment

Background: Methamphetamine use disorder (MUD) associates with cognitive impulsivity deficits. However, few studies have examined longitudinal changes in cognition, and it remains unclear if deficits resolve during early recovery.Objectives: To compare: (1) cognitive function of individuals with MUD at treatment onset and six-weeks later with controls tested over the same period; (2) cognitive changes in MUD-individuals who remained abstinent versus relapsed.Method: We recruited 108 participants meeting DSM-IV-TR criteria for methamphetamine dependence (81 males) and 50 demographically matched controls (38 males); 77 methamphetamine- dependent participants (59 males) and 48 controls (36 males) were retained at follow-up. We administered response inhibition, delay discounting and uncertainty-based decision-making tests at both endpoints. Relapse was defined as methamphetamine concentrations >0.4 ng/mg at follow-up in hair toxicology.Results: We found a significant time-by-group interaction on uncertainty-based decision-making (effect size: η² = .05), although post-hoc tests to disentangle this interaction yielded inconclusive results (p-range = .14-.40; BF₁₀-range = 0.43-1.67). There were no significant time-by-group interactions on response inhibition or delay discounting, with the former likely a null effect (η²-interaction = .003 and .02; BF_incl = 0.23 and 0.71). There were no significant differences in cognitive recovery between individuals who maintained abstinence (n = 12) versus relapsed (n = 65) (η²-range = .003-.04), although evidence was inconclusive toward whether findings reflected true null effects (BF_incl-range = 0.33-0.75).Conclusion: We did not find evidence that MUD-related cognitive impulsivity deficits improve beyond practice effects over 6 weeks. Findings do not support previous, albeit conflicting, evidence of early recovery of cognitive deficits in MUD.

Apathy is associated with poorer abstinence self-efficacy in individuals with methamphetamine dependence

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Used an apathy composite T-score approach validated in methamphetamine-dependence.

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Apathy, above other factors, associated with poorer drug abstinence self-efficacy.

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Methamphetamine use characteristics unrelated to drug abstinence self-efficacy.

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Social peer pressure was riskiest situation for potential methamphetamine relapse.

Background

Confidence in one’s ability to achieve and maintain drug abstinence (i.e., abstinence self-efficacy) is a strong predictor of substance use treatment outcomes. Neurobehavioral factors that may interfere with abstinence self-efficacy are less well established, particularly in methamphetamine (METH). This study investigated whether apathy, which is highly prevalent during active METH use and periods of abstinence, influences abstinence self-efficacy among METH dependent individuals.

Methods

Sixty-six participants with lifetime METH dependence and METH abuse/METH dependence diagnoses within the last 18 months (mean age [SD] = 39.5 years [10.7]), and no severe psychiatric or neurological diseases, completed the Methamphetamine Self-Efficacy Scale (MSES), alongside a comprehensive neurobehavioral evaluation. The MSES presents six situations that may lead to relapse and collects self-report ratings for two subscales: “Confidence” (i.e., confidence in one’s ability to abstain from using METH, or METH abstinence self-efficacy) and “Temptation” (i.e., how tempted one is to use METH) with regard to each situation. Apathy was measured using a composite T-score comprised of items and scales from three well-validated, self-report assessments.

Results

Multivariable linear regression found that higher Apathy T-scores were significantly associated with lower Confidence ratings (i.e., poorer METH abstinence self-efficacy; p < .05), independent of potentially relevant factors (e.g., Temptation to use METH, comorbid HIV disease, and neurocognitive impairment).

Conclusions

Elevated apathy may adversely impact one’s confidence to abstain from METH use. Findings highlight the importance of addressing apathy in order to improve METH abstinence self-efficacy, which may subsequently increase the likelihood of successful METH treatment outcomes.

Profiles of patients with cocaine and alcohol use disorder based on cognitive domains and their relationship with relapse

BACKGROUND

Relapse in drug use constitutes a research topic on addiction that is relevant for understanding both the addictive process and its clinical implications. The objective of this study was to explore if it is possible to identify patient profiles according to their performance on cognitive tasks whilst examining the relationship between such profiles and relapse.

METHODS

The sample consisted of 222 patients with dependence on cocaine and / or alcohol, of which 86 % were men. Cognitive domains related to salience, decision- making, and emotional processing were measured.

RESULTS

Latent class analysis revealed three patient profiles that differ in terms of performance on cognitive tasks. Two of these profiles are clearly differentiated in terms of their execution of the impulsive decision-making task. The third patient profile, unlike the latter two, is composed of patients with severe alterations in the three domains evaluated. Analysis revealed that patients in Profile 3 are those with the highest rates of relapse in cocaine (Profile 1 = 40.3 %; Profile 2 = 35.6 %; Profile 3 = 69.2 %; Chi2 = 9.169; p < .05) and cocaine and alcohol use (Profile 1 = 55.1 %; Profile 2 = 54.1 %; Profile 3 = 80 %; Chi2 = 6.698; p < .05).

CONCLUSIONS

The results support the postulates of the I-RISA model. From a clinical perspective, these findings highlight the need for a comprehensive evaluation of the cognitive domains involved in addiction.

Maternal alcohol dependence and harsh caregiving across parenting contexts: The moderating role of child negative emotionality

Parental alcohol dependence is a significant risk factor for harsh caregiving behaviors; however, it is unknown whether and how harsh caregiving changes over time and across parenting contexts for alcohol-dependent mothers. Furthermore, to our knowledge, no studies have examined whether and how distinct dimensions of child characteristics, such as negative emotionality modulate harsh caregiving among alcohol-dependent mothers. Guided by parenting process models, the present study examined how two distinct domains of children's negative emotionality-fear and frustration-moderate the association between maternal alcohol dependence and maternal harshness across discipline and free-play contexts. A high-risk sample of 201 mothers and their two-year-old children were studied over a one-year period. Results from latent difference score analyses indicated that harsh parenting among alcohol-dependent mothers increased over time in the more stressful discipline context, but not in the parent-child play context. This effect was maintained even after controlling for other parenting risk factors, including other forms of maternal psychopathology. Furthermore, this increase in harsh parenting was specific to alcohol-dependent mothers whose children were displaying high levels of anger and frustration. Findings provide support for specificity in conceptualizations of child negative emotionality and parenting contexts as potential determinants of maladaptive caregiving among alcohol-dependent mothers.

Choosing the Optimal Brain Target for Neuromodulation Therapies as Alcohol Addiction Progresses—Insights From Pre-Clinical Studies

Purpose of the Review

Development of addiction involves a transition from reward-driven to habitual behavior, mediated by neuroplastic changes. Based on preclinical findings, this article article reviews the current knowledge on the use of neuromodulation therapies to target alcohol addiction and essentially reduce relapse.

Recent Findings

To date, only a limited number of preclinical studies have investigated the use of neuromodulation in alcohol addiction, with the focus being on targeting the brain reward system. However, as addiction develops, additional circuits are recruited. Therefore, a differential setup may be required when seeking to alter the chronic alcohol-dependent brain, as opposed to treating earlier phases of alcohol addiction.

Summary

To promote enduring relapse prevention, the choice of brain target should match the stage of the disorder. Further studies are needed to investigate which brain areas should be targeted by neuromodulating strategies, in order to sufficiently alter the behavior and pathophysiology as alcohol addiction progresses.

Perceived neighborhood disorder and frequency of marijuana use among emerging adult African American females

Emerging adult African American females are at increased risk for cannabis use disorders. Ecological models suggest that African Americans' increased risk for substance use disorders and associated adverse outcomes may result from chronic exposure to contextual disadvantages, such as living in economically deprived and disorganized communities. However levels of vulnerability for developing cannabis use disorders vary, even among residents of disadvantaged neighborhoods. Therefore, studies focused on within group differences are necessary. This study examined the relationship between frequency of marijuana use and perceived neighborhood disorder. The sample included 117 African American emerging adult females (M_age = 23.6 ± 3.4). After providing informed consent, participants completed a semi-structured interview that included the Neighborhood Environment Scale and a self-report measure of marijuana use. Additionally, participants provided a urine sample that was tested for the presence of psychoactive drugs. 46% tested positive for marijuana and 45% reported using marijuana in the past 30 days. 27% reported frequent/heavy use. Results from multinomial logistic regression analysis indicated a significant relationship between perceived neighborhood disorder and heavy marijuana use (AOR = 3.3; 95% CI = 1.06 - 10.29). Findings suggest African American emerging adult female residents of economically disadvantaged neighborhoods who appraise their environments as disorganized may be at heighten risk for problematic marijuana use and should be targeted for intervention. Moreover, the findings support the need for multi-systems interventions. As policy makers consider the legalization of marijuana, it is important that differences in marijuana use behaviors and negative outcomes across groups and contexts are taken into consideration.

Impulsivity and Cognitive Flexibility as Neuropsychological Markers for Suicidality: A Multi-Modal Investigation Among Military Veterans with Alcohol Use Disorder and PTSD

To examine relations between self-report and behavioral measures of impulsivity and cognitive flexibility with suicidal ideation and self-harm and suicide attempt history. Methods: Eighty-seven military veterans who met DSM-5 diagnostic criteria for alcohol use disorder (AUD) and posttraumatic stress disorder (PTSD) were evaluated for current suicidal ideation and self-harm, suicide attempt history, impulsivity, and cognitive flexibility. Results: Higher levels of self-reported impulsivity were associated with greater suicidal ideation and self-harm and lower behavioral inhibition was associated with greater likelihood of endorsing a suicide attempt. Conclusion: Use of multi-modal assessment of impulsivity and cognitive flexibility may aid in suicide screening and intervention among vulnerable and high-risk populations.

Distinct Region- and Time-Dependent Functional Cortical Adaptations in C57BL/6J Mice after Short and Prolonged Alcohol Drinking

Alcohol (ethanol) use disorder is associated with changes in frontal cortical areas including the anterior cingulate cortex (ACC) and orbitofrontal cortex (OFC) that contribute to cognitive deficits, uncontrolled drinking, and relapse. Acute ethanol exposure reduces intrinsic excitability of lateral OFC (lOFC) neurons, while chronic exposure and long-term drinking influence plasticity of intrinsic excitability and function of glutamatergic synapses. However, the time course that these adaptations occur across a history of ethanol drinking is unknown. The current study examined whether short-term and long-term voluntary ethanol consumption using an intermittent access paradigm would alter the biophysical properties of deep-layer pyramidal neurons in the ACC and lOFC. Neuronal spiking varied in the ACC with an initial increase in evoked firing after 1 d of drinking followed by a decrease in firing in mice that consumed ethanol for one week. No difference in lOFC spike number was observed between water controls and 1-d ethanol drinking mice, but mice that consumed ethanol for one week or more showed a significant increase in evoked firing. Voluntary ethanol drinking for 4 weeks also produced a total loss of ethanol inhibition of lOFC neurons. There was no effect of drinking on excitatory or inhibitory synaptic events in ACC or lOFC neurons across all time points in this model. Overall, these results demonstrate that voluntary drinking alters neuronal excitability in the ACC and lOFC in distinct ways and on a different time scale that may contribute to the impairment of prefrontal cortex-dependent behaviors observed in individuals with alcohol use disorder (AUD).

Cognitive profiles in persons with opioid use disorder enrolled in methadone treatment

Cognitive impairment is common in persons with opioid use disorder and associated with poor treatment outcomes, including elevated risk for relapse. Much less is known about the underlying structure of these deficits and the possible presence of cognitive phenotypes. A total of 177 adults (average 42.2 years of age, 52.0% male, 65.5% Caucasian) enrolled in a methadone maintenance treatment program completed the NIH Toolbox as part of a larger project. Cluster analyses revealed a 2-cluster solution-persons with intact cognitive function in all domains (n = 93; Intact) and those with impairments on tests of attention and executive function (n = 83; Impaired). Follow-up analyses revealed that the Impaired group was slightly older, more likely to self-identify as a racial/ethnic minority, and less likely to report consuming alcohol four or more times per week. These findings suggest the existence of distinct cognitive profiles in persons with opioid use disorder and encourage further examination, particularly studies to examine the possible benefits of routine screening for cognitive impairment as part of substance use treatment.

Cognitive deficits in methamphetamine addiction: Independent contributions of dependence and intelligence

BACKGROUND

Methamphetamine's effects on brain function have been associated with cognitive deficits, which have a negative impact on clinical outcomes. However, it remains unclear if cognitive deficits relate to methamphetamine dependence (potentially amenable to abstinence and retraining) or background characteristics, mental health and other drug use. We tested the association between methamphetamine dependence and cognitive performance, while factoring in the impact of background characteristics, depressive symptoms and tobacco, alcohol and cannabis use.

METHOD

The sample comprised 108 treatment-seeking participants who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV TR) criteria for methamphetamine dependence and 50 socio-demographically matched controls. We administered a comprehensive neuropsychological test battery (delay discounting, decision making, disinhibition, episodic and working memory) and examined cognitive deficits in methamphetamine users after taking into account socio-demographic characteristics, tobacco, alcohol and cannabis use, and depressive symptoms.

RESULTS

Hierarchical multiple regression analyses showed that methamphetamine dependence was associated with poorer performance in decision-making and disinhibition over and above other predictors, while IQ better explained performance in episodic and working memory. Although duration of methamphetamine use was linked to disinhibition, other patterns of methamphetamine use (including dose and frequency) were not consistently related to performance.

CONCLUSIONS

Methamphetamine dependence impacts inhibitory control and decision-making, whereas lower IQ associates with memory/working memory deficits among methamphetamine users. Findings suggest the need to target disinhibition and impulsive decision-making as part of methamphetamine dependence treatment, while buffering the impact of IQ on memory systems.

Sex-dependent differences in ethanol inhibition of mouse lateral orbitofrontal cortex neurons

Biological differences between males and females likely influence responses to alcohol and the propensity to engage in excessive drinking. In both humans and rodents, females escalate alcohol use and develop addiction-like behaviors faster than males, while males exhibit more severe withdrawal symptoms during abstinence. The mechanisms underlying these differences are not yet known but may reflect fundamental differences in the ethanol sensitivity of neurons in reward and control areas of the brain. To address this question, we recorded current-evoked spiking of lateral orbitofrontal cortex (lOFC) neurons in male and female C57BL/6J mice following acute and chronic exposure to ethanol. Ethanol (11-66 mM) reduced firing of lOFC neurons but produced less inhibition in neurons from female mice. As previously reported for male mice, the glycine receptor blocker strychnine blocked ethanol inhibition of spiking of lOFC neurons from female mice and prevented the ethanol-induced increase in tonic current. Following chronic intermittent ethanol (CIE) exposure, current-evoked spiking of lOFC neurons was significantly enhanced with a greater effect observed in males. After CIE treatment, acute ethanol had no effect on spiking in neurons from male mice, while it produced a slight but significant decrease in firing in females. Finally, like male mice, the inhibitory effect of the glycine transport inhibitor sarcosine was blunted in CIE-exposed female mice. Together, these results suggest that while lOFC neurons in male and female mice are similarly affected by ethanol, there are significant differences in sensitivity that may contribute to differences in alcohol actions between males and females.

Demographic and Clinical Characteristics of Regular GHB-Users with and without GHB-Induced Comas

Gamma hydroxybutyric acid (GHB) has been used recreationally for nearly three decades and its chronic use is frequently associated with serious adverse events including GHB-intoxication with GHB-induced comas. Moreover, despite its low prevalence, the number of individuals with GHB-use disorders is steadily increasing. However, the risk-factors associated with chronic GHB-use or the development of a GHB-use disorders remain poorly understood. Purpose: This study aims to profile two types of GHB-users, those with and those without GHB-induced comas. Methods: We included 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users without a coma (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). Participants completed self-reported questionnaires in order to assess their demographic and clinical features, and their use profile of GHB and other drugs. Results: The typical GHB user in our sample was young, single, living alone, well-educated, and a student. The GHB-Coma group had lower self-control and reported higher negative affect than the GHB-NoComa group. GHB-Coma participants were heavier GHB users and mostly used GHB alone at home, whereas the GHB-NoComa group mostly used GHB with friends and in nightclubs. Remarkably, the majority of participants were not concerned about potential neurocognitive impairments induced by GHB-intoxication and/or GHB-induced comas. Conclusion: In this assessment, different profiles for recreational users with and without GHB-induced comas were well expressed. Their description contributes to a better understanding of the risk factors associated with recreational GHB-use, GHB-induced coma, and the development of GHB-use disorders.

The association between executive functioning and parental stress and psychological distress is mediated by parental reflective functioning in mothers with substance use disorder

Mothers with a substance use disorder (SUD) have been found to exhibit heightened experience of stress and deficits in executive functioning (EF) and in parental reflective functioning (PRF). Although experiences of stress, EF and PRF are important for caregiving capacities; no studies have explored associations between the phenomena in mothers with SUD. This study aimed to examine the association between EF (working memory, inhibition, and cognitive flexibility) and different forms of stress (parental stress, general life stress, and psychological distress) in 43 mothers with SUD with infants. We further aimed to investigate whether PRF had a mediating function between EF and the experience of stress. The mothers completed self-report questionnaires regarding experiences of different types of stress, and we also used neuropsychological tests to assess EF and a semistructured interview to assess PRF. Results identified problems in EF were associated with higher parental stress and psychological distress but not with general life stress. Cognitive flexibility contributed uniquely to variance in parental stress, whereas working memory was a unique contributor to variance in psychological distress. PRF had a mediating function between EF and parental stress and between EF and psychological distress. Findings highlight the importance of considering individual differences in PRF when targeting EF in interventions trying to reduce the experience of parental stress and psychological distress in mothers with SUD.

Impact of Substance Use Disorder Pharmacotherapy on Executive Function: A Narrative Review

Substance use disorders are chronic, relapsing, and harmful conditions characterized by executive dysfunction. While there are currently no approved pharmacotherapy options for stimulant and cannabis use disorders, there are several evidence-based options available to help reduce symptoms during detoxification and aid long-term cessation for those with tobacco, alcohol and opioid use disorders. While these medication options have shown clinical efficacy, less is known regarding their potential to enhance executive function. This narrative review aims to provide a brief overview of research that has investigated whether commonly used pharmacotherapies for these substance use disorders (nicotine, bupropion, varenicline, disulfiram, acamprosate, nalmefene, naltrexone, methadone, buprenorphine, and lofexidine) effect three core executive function components (working memory, inhibitory control and cognitive flexibility). While pharmacotherapy-induced enhancement of executive function may improve cessation outcomes in dependent populations, there are limited and inconsistent findings regarding the effects of these medications on executive function. We discuss possible reasons for the mixed findings and suggest some future avenues of work that may enhance the understanding of addiction pharmacotherapy and cognitive training interventions and lead to improved patient outcomes.

The Effect of High-Frequency Repetitive Transcranial Magnetic Stimulation on Emotion Processing, Reappraisal, and Craving in Alcohol Use Disorder Patients and Healthy Controls: A Functional Magnetic Resonance Imaging Study

Impaired cognitive-motivational functioning is present in many psychiatric disorders, including alcohol use disorder (AUD). Emotion regulation is a key intermediate factor, relating to the (cognitive) regulation of emotional and motivational states, such as in regulation of craving or negative emotions that may lead to relapse in alcohol use. These cognitive-motivational functions, including emotion regulation, are a target in cognitive behavioral therapy and may possibly be improved by neurostimulation techniques. The present between-subjects, single-blind study assesses the effects of sham-controlled high-frequency neuronavigated repetitive transcranial magnetic stimulation (10 Hz) of the right dorsolateral prefrontal cortex (dlPFC) on several aspects relevant for emotion regulation (emotion processing and reappraisal abilities) and related brain activity, as well as self-reported craving in a sample of alcohol use disorder patients (AUD; n = 39) and healthy controls (HC; n = 36). During the emotion reappraisal task, participants were instructed to either attend or reappraise their emotions related to the negative, positive, neutral, and alcohol-related images, after which they rated their experienced emotions. We found that repetitive transcranial magnetic stimulation (rTMS) reduces self-reported experienced emotions in response to positive and negative images in AUD patients, whereas experienced emotions were increased in response to neutral and positive images in HCs. In the functional magnetic resonance imaging (fMRI) analyses, we found that rTMS reduces right dlPFC activity during appraisal of affective images relative to sham stimulation only in AUD patients. We could not confirm our hypotheses regarding the effect of rTMS craving levels, or on reappraisal related brain function, since no significant effects of rTMS on craving or reappraisal related brain function were found. These findings imply that rTMS can reduce the emotional impact of images as reflected in blood oxygenation level-dependent (BOLD) response, especially in AUD patients. Future studies should replicate and expand the current study, for instance, by assessing the effect of multiple stimulation sessions on both explicit and implicit emotion regulation paradigms and craving, and assess the effect of rTMS within subgroups with specific addiction-relevant image preferences. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02557815.

Effects of Non-invasive Neuromodulation on Executive and Other Cognitive Functions in Addictive Disorders: A Systematic Review

Background: In order to improve the current treatment of addictive disorders non-invasive neuromodulation over the dorsolateral prefrontal cortex (DLPFC) has gained attention. The DLPFC is crucially involved in executive functioning, functions which are related to the course of addictive disorders. Non-invasive stimulation of the DLPFC may lead to changes in executive functioning. Currently an overview of effects of neuromodulation on these functions is lacking. Therefore, this systematic review addresses the effects of non-invasive neuromodulation on executive functioning in addictive disorders. Methods: The current review is conducted and reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses for Protocols 2015 (PRISMA-P 2015) guidelines and has been registered in PROSPERO International Prospective Register of Systematic Reviews (https://www.crd.york.ac.uk/prospero/, registration number: CRD42018084157). Original articles were searched using the Ovid MEDLINE, Embase and PsycINFO database. Results: The systematic search resulted in 1,228 unique studies, of which sixteen were included in the current review. Some of these studies do not address the classic definition of executive functions, but another cognitive function. However, they were included in this review since the field is small and still under development and we aim to give an inclusive overview in its broadest sense. The following executive and other cognitive functioning domains were assessed: attention, cognitive flexibility, response inhibition, memory and learning, problem solving, social cognition, risk taking, cognitive bias modification and overall executive functioning. The executive function domain most positively affected was social cognition followed by memory & learning, response inhibition, cognitive flexibility and attention. Conclusions: The studies addressed in the current review used a large variability of stimulation protocols and study designs which complicates comparability of the results. Nevertheless, the results of these studies are promising in light of improvement of current treatment. Therefore, we recommend future studies that compare the effect of different types of stimulation, stimulation sides and number of stimulation sessions in larger clinical trials. This will significantly increase the comparability of the studies and thereby accelerate and clarify the conclusion on whether non-invasive neuromodulation is an effective add-on treatment for substance dependence.