Changes in processing speed during early abstinence from alcohol dependence.

BACKGROUND: Processing speed is a task-independent construct underpinning more complex goal-related abilities. Processing speed is impaired in alcohol dependence (AD) and is linked to relapse, as are the functions it underpins. Reliable measurement of processing speed may allow tracking of AD recovery trajectories and identify patients requiring additional support. AIMS: To assess changes in reaction time (RT) from baseline (at the start of a detoxification programme) across early abstinence. METHODS: Vibrotactile RT was assessed in early recovery between days 3 and 7 of treatment in 66 individuals with AD (25 females; aged 19-74, 44.60 ± 10.60 years) and against 35 controls tested on one occasion (19 females; 41.00 ± 13.60), using two multivariate multiple regressions. A mixed multivariate analysis of covariance (MANCOVA) of available AD data (n = 45) assessed change in RT between timepoints and between treatment settings (outpatient vs inpatient). RESULTS: The group (AD vs control) significantly predicted choice RT at baseline and follow-up but did not significantly predict simple RT or RT variability, which is inconsistent with previous findings. At follow-up, mental fatigue was also predicted by the group, and MANCOVA indicated that this had worsened in inpatients but improved in outpatients. CONCLUSIONS: Recovery of RT measures so early in the treatment journey was not in line with previous research which indicates persisting deficits. The interaction between setting and timepoint indicates that despite being typically less medically complex, outpatients require ongoing support and monitoring during their recovery.

The Associations among Perceived Courtesy Stigma, Health and Social Behaviours in Family Members and Friends of People Who Use Substances: An Ecological Momentary Assessment Study.

Background: The stigma and discrimination experienced by individuals with an alcohol/substance use disorder often extends to the family members and friends who provide care, which is known as courtesy stigma. This courtesy stigma can lead to isolation, poor mental health and might impact the quality-of-care these individuals provide. The aim of this study was to examine the frequency of experienced courtesy stigma/discrimination in individuals in a family support service for a loved one's substance use, and to examine any cross-sectional associations with changes in mood, health- and social-related outcomes. Methods: Thirty-six individuals (25 female) with a mean age of 51.91 years took part in an ecological momentary assessment study in which the experience of courtesy stigma/discrimination and measures of mood, health (e.g. alcohol use, nicotine use, healthy eating, sleep, physical activity) and social connections were taken 3 times per day for fourteen days. Results: Across 1029 competed assessments (compliance ∼68%), there were 122 (∼11%) reports of courtesy stigma/discrimination. The most common sources of stigma/discrimination were from family members (∼43% of occurrences) and friends (∼31% of occurrences). Experiencing this stigma/discrimination was associated with increases in alcohol and nicotine use, as well as reductions in healthy eating, physical activity, sleep, social connections, and mood. Conclusions: The experience of courtesy stigma/discrimination was common in a sample of individual's who support a loved one with alcohol or substance use disorder. These experiences are associated with changes in health and social behaviors and may lead to a poorer quality of care.

Recovery of neuropsychological function following abstinence from alcohol in adults diagnosed with an alcohol use disorder: Systematic review of longitudinal studies.

BACKGROUND: Alcohol use disorders (AUD) associate with structural and functional brain differences, including impairments in neuropsychological function; however, reviews (mostly cross-sectional) are inconsistent with regards to recovery of such functions following abstinence. Recovery is important, as these impairments associate with treatment outcomes and quality of life. OBJECTIVE(S): To assess neuropsychological function recovery following abstinence in individuals with a clinical AUD diagnosis. The secondary objective was to assess predictors of neuropsychological recovery in AUD. METHODS: Following the preregistered protocol (PROSPERO: CRD42022308686), APA PsycInfo, EBSCO MEDLINE, CINAHL, and Web of Science Core Collection were searched between 1999-2022. Study reporting follows the Joanna Briggs Institute (JBI) Manual for Evidence Synthesis, study quality was assessed using the JBI Checklist for Cohort Studies. Eligible studies were those with a longitudinal design that assessed neuropsychological recovery following abstinence from alcohol in adults with a clinical diagnosis of AUD. Studies were excluded if participant group was defined by another or co-morbid condition/injury, or by relapse. Recovery was defined as function reaching 'normal' performance. RESULTS: Sixteen studies (AUD n = 783, controls n = 390) were selected for narrative synthesis. Most functions demonstrated recovery within 6-12 months, including sub-domains within attention, executive function, perception, and memory, though basic processing speed and working memory updating/tracking recovered earlier. Additionally, verbal fluency was not impaired at baseline (while verbal function was not assessed compared to normal levels), and concept formation and reasoning recovery was inconsistent. CONCLUSIONS: These results provide evidence that recovery of most functions is possible. While overall robustness of results was good, methodological limitations included lack of control groups, additional methods to self-report to confirm abstinence, description/control for attrition, statistical control of confounds, and of long enough study durations to capture change.

Improving access to treatment for alcohol dependence in primary care: A qualitative investigation of factors that facilitate and impede treatment access and completion.

BACKGROUND: Timely intervention for people with alcohol dependence in primary care is needed. Primary care services have a key role in supporting adults with alcohol dependence and require appropriate provision of services. OBJECTIVE: To examine the perceptions of both primary care practitioners and adults with alcohol dependence regarding service provision and to describe help seeking behaviours for adults with alcohol dependence. DESIGN AND SETTING: Qualitative study consisting of semi-structured interviews with adults with alcohol dependence, healthcare professionals and staff members of specialist alcohol services who had previous or current experience in the management, treatment, or referral of adults with alcohol dependence in Northwest England. METHOD: Interviews were conducted with ten adults with alcohol dependence and 15 staff. Data were analysed thematically, applying principles of constant comparison. RESULTS: Three themes were identified following inductive thematic analysis. The first theme, point of access relates to current service provision being reactive rather than preventative, the stigma associated with alcohol dependence and a person's preparedness to change. The second theme identified was treatment process and pathways that highlights difficulties of engagement, mental health support, direct access and person-centred support. The third theme was follow-up care and discusses the opportunities and threats of transitional support or aftercare for alcohol dependence, signposting and peer support. CONCLUSION: There are clear opportunities to support adults with alcohol dependence in primary care and the need to increase provision for timely intervention for alcohol related issues in primary care.

Little Evidence for the Role of Disgust Sensitivity in Implicit Disgust to Images of White People Engaged in Injecting Drug Use (IDU).

Background: Previous research has shown that People Who Inject Drugs (PWID) are subject to public stigma, which affects access to, and provision and quality of, treatment and support services. Less is known about the socio-cognitive processes that support the development and maintenance of public stigma toward PWID. The present study investigated the role of disgust sensitivity in implicit disgust to injecting drug use. Methods: 126 participants took part in an online Implicit Association Task (IAT) measuring implicit disgust to pictorial stimuli of injecting drug use or medical injecting. Participants also completed The Disgust Scale Revised, Injecting Phobia Scale (Short Form), Attitudes to People Who Use Drugs (PWUD) scale and a substance use inventory. Results: Average IAT score was negative indicating significantly higher implicit disgust to injecting drug use. Hierarchical linear regression found that injecting phobia predicted implicit disgust to injecting drug use. Questionnaire measures of disgust did not predict implicit disgust. While animal reminder disgust and injecting phobia were significantly correlated with each other, animal reminder disgust did not predict implicit disgust scores. Conclusions: On the basis of our findings, stigma toward PWID may not be a result of feelings of disgust toward injecting drug use. We discuss findings in the context of the underlying cortical processes supporting implicit and explicit representations of disgust. Future research should seek to investigate neurophysiological evidence for disgust to and stigmatization of injecting drug use and the potential role of domains of disgust in this.

Younger, drunk, and fast: Paradoxical rapid reaction time in hazardous drinkers.

BACKGROUND: Research consistently links hazardous alcohol use with reduced cognitive function but is less consistent with regard to processing speed, which underpins many cognitive functions. Using vibrotactile perception to assess cognitive function may have benefits over other sensory stimuli, as this method gives lower variability in reaction time (RT) and shorter latency. AIMS: This study aimed to assess performance on vibrotactile simple and choice RT tasks between hazardous and non-hazardous drinkers. METHODS: Participants (n = 86) completed vibrotactile tasks and alcohol, mood and subjective function (Executive Function Index (EFI)) questionnaires. Multivariate analyses of covariance were performed on average RT scores, and on EFI scores, to investigate function, and a bivariate correlation assessed the relationships between subjective and objective measures. RESULTS: Hazardous drinkers exhibited significantly faster choice RT. With regard to subjective executive function, Strategic Planning and Impulse Control were significantly better in non-hazardous drinkers. Finally, Organisation and Impulse Control both significantly positively correlated with choice and simple RT, indicating that as subjective function improved, RT increased (a decline in performance). CONCLUSIONS: These results are considered in the context of the premature ageing hypothesis, impulsivity and the impact of alcohol use on various neurotransmitter systems. Furthermore, the poorer subjective function in young hazardous drinkers indicates a possible metacognitive deficit, increased effort or issues with vibrotactile perception as a cognitive function assessment in this group.

Prevalence and incidence of alcohol dependence: cross-sectional primary care analysis in Liverpool, UK.

OBJECTIVES: Liverpool has high prevalence of alcohol use disorders (AUDs) compared with the rest of the UK. Early identification and referral in primary care would improve treatment for people with AUD. This study aimed to identify changes in prevalence and incidence of AUD in primary care in Liverpool, to identify local need for specialist services. DESIGN: Cross-sectional retrospective analysis of electronic health records. SETTING: National Health Service (NHS) Liverpool Clinical Commissioning Group (CCG) primary care. In total, 62 of the 86 general practitioner (GP) practices agreed to share their anonymised Egton Medical Information Systems (EMIS) data from 1 January 2017 to 31 December 2021. PARTICIPANTS: Patients aged over 18 years with a SNOMED code for alcohol dependence (AD) or hazardous drinking (N=4936). Patients were excluded if they had requested that their data was not to be shared, and practices were excluded if they opted out (N=2) or did not respond to the data sharing request (N=22). PRIMARY AND SECONDARY OUTCOMES: Prevalence and incidence of AUD diagnoses in primary care over the 5-year period; demographic profile of patients (sex, age, ethnicity, occupation); GP postcode; alcohol-related medications; and psychiatric and physical comorbidities. RESULTS: There were significant decreases in incidence of AD and hazardous drinking diagnoses over the 5 years (p<0.001 in all cases). Prevalence showed less change over time. Diagnoses were significantly higher in more deprived areas (Indices of Multiple Deprivation decile 1 vs 2-10). Overall pharmacotherapy prescriptions were lower than national estimates. CONCLUSIONS: There are low levels of identification of AUDs in primary care in Liverpool, and this is decreasing year on year. There was weak evidence to suggest patients in the most deprived areas are less likely to receive pharmacotherapy once diagnosed. Future research should seek to investigate practitioner and patient perspectives on barriers and facilitators to management of AUDs in primary care.

Opioid prescribing and social deprivation: A retrospective analysis of prescribing for CNCP in Liverpool CCG.

BACKGROUND: Treating Chronic Non-Cancer Pain (CNCP) with long-term, high dose and more potent opioids puts patients at increased risk of harm, whilst providing limited pain relief. Socially deprived areas mapped from Index of Multiple Deprivation (IMD) scores show higher rates of high dose, strong opioid prescribing compared to more affluent areas. OBJECTIVE: To explore if opioid prescribing is higher in more deprived areas of Liverpool (UK) and assess the incidence of high dose prescribing to improve clinical pathways for opioid weaning. DESIGN AND SETTING: This retrospective observational study used primary care practice and patient level opioid prescribing data for N = 30,474 CNCP patients across Liverpool Clinical Commissioning Group (LCCG) between August 2016 and August 2018. METHOD: A Defined Daily Dose (DDD) was calculated for each patient prescribed opioids. DDD was converted into a Morphine Equivalent Dose (MED) and patients stratified according to high (≥120mg) MED cut off. The association between prescribing and deprivation was analysed by linking GP practice codes and IMD scores across LCCG. RESULTS: 3.5% of patients were prescribed an average dose above 120mg MED/day. Patients prescribed long-term, high dose, strong opioids were more likely to be female, aged 60+, prescribed three opioids and reside in the North of Liverpool where there is a higher density of areas in the IMD most deprived deciles. CONCLUSION: A small but significant proportion of CNCP patients across Liverpool are currently prescribed opioids above the recommended dose threshold of 120mg MED. Identification of fentanyl as a contributor to high dose prescribing resulted in changes to prescribing practice, and reports from NHS pain clinics that fewer patients require tapering from fentanyl. In conclusion, higher rates of high dose opioid prescribing continue to be evident in more socially deprived areas further increasing health inequalities.

Feasibility study of a Behavioural Intervention for Opioid Reduction (BIOR) for patients with chronic non-cancer pain in primary care: a protocol.

INTRODUCTION: Around 30%-50% of adults suffer moderate to severe chronic pain not caused by cancer. Significant numbers are treated with opioids which over time may cease to be effective and produce side effects (eg, nausea, drowsiness and constipation). Stopping taking opioids abruptly can cause unpleasant withdrawal effects. Tapering in small steps is recommended, though some patients might struggle and need support, particularly if they have limited access to pain management alternatives. Awareness of the potential risks as well as benefits of tapering should be explored with patients. METHODS AND ANALYSIS: A randomised controlled pilot feasibility study to investigate the effectiveness and feasibility of reducing high doses of opioids through a tapering protocol, education and support in primary care. Working with NHS Knowsley Place, we will identify patients taking 50 mg or above morphine equivalent dose of opioids per day to be randomly allocated to either the tapering group or tapering with support group. At an initial joint appointment with a pain consultant and General Practitioner (GP) GP tapering will be discussed and negotiated. Both groups will have their opioid reduced by 10% per week. The taper with support group will have access to additional support, including motivational counselling, realistic goal setting and a toolkit of resources to promote self-management. Some patients will successfully reduce their dose each week. For others, this may be more difficult, and the tapering reduction will be adjusted to 10% per fortnight. We assess opioid use, pain and quality of life in both groups at the start and end of the study to determine which intervention works best to support people with chronic pain who wish to stop taking opioids. ETHICS AND DISSEMINATION: The Behavioural Intervention for Opioid Reduction feasibility study has been granted full approval by Liverpool Central Research Ethics Committee on 7 April 2022 (22/NW/0047). The current protocol version is V.1.1, date 6 July 2022. Results will be published in peer-reviewed journals and disseminated to patient stakeholders in a lay summary report available on the project website and in participating GP surgeries. TRIAL REGISTRATION NUMBER: ISRCTN 30201337.

Effects of media representations of drug related deaths on public stigma and support for harm reduction.

BACKGROUND: Drug related deaths (DRD) are at historically high levels in the United Kingdom (UK), but some approaches that have the potential to reduce risk of mortality remain controversial. Public support makes an important contribution to drug policy development but there are high levels of public stigma towards people who use drugs (PWUD), and this is partly shaped by media representations. We investigated whether depiction of the characteristics of decedents represented in news articles about DRD was associated with differences in stigmatising attitudes and support for harm reduction policy. METHODS: We undertook a cross-sectional online study with a randomised design, conducted with a nationally representative sample (UK). Participants (N = 1280) were randomly presented with one of eight simulated news stories that reported on a DRD that differed with respect to drug (ecstasy or heroin), and the gender (male or female) and age (younger or older) of the decedent. Data were analysed using MANOVA. RESULTS: Data were obtained for 1248 participants (51.0% female; mean age 45.7±15.4). Stigma was higher towards depictions of male, older, and heroin deaths (all p < .001). Harm reduction support was higher in those participants seeing older compared to younger subjects (p = .035), and the older ecstasy decedent compared to younger decedent (p = .029). CONCLUSION: Presentation of some types of DRD are associated with higher public stigma towards the decedent than others. Those groups developing agenda-setting activities designed to reduce stigma or foster public support for harm reduction policies should consider the different ways in which audiences may respond to the depiction and framing of DRD in news media.

Recovery of neuropsychological function following abstinence from alcohol in adults diagnosed with an alcohol use disorder: Protocol for a systematic review of longitudinal studies.

BACKGROUND: Alcohol use disorders (AUD) associate with structural and functional brain differences, including impairments in neuropsychological functions; however, review level research (largely cross-sectional) is inconsistent with regards to recovery of such functions following abstinence. Such recovery is important, as these impairments associate with treatment outcomes and quality of life. OBJECTIVE(S): To assess neuropsychological function recovery following abstinence in individuals with a clinical AUD diagnosis. The secondary objective is to assess predictors of neuropsychological recovery in AUD. METHODS: Four electronic databases (APA PsycInfo, EBSCO MEDLINE, CINAHL, Web of Science Core Collection) will be searched between 1999-2022, with search strategies adapted for each source. Study reporting will follow the Joanna Briggs Institute (JBI) Manual for Evidence Synthesis, study quality will be assessed using the JBI Checklist for Cohort Studies. Eligible studies are those with a longitudinal design that assessed neuropsychological recovery following abstinence from alcohol in adults with a clinical diagnosis of AUD. Studies will be excluded if participant group is defined by another or co-morbid condition/injury, or by relapse. RESULTS: This is an ongoing review. As of July 2022, the review protocol is registered on PROSPERO (CRD42022308686), searches have been conducted, and screening is in progress. Results are predicted to be complete by October 2022. CONCLUSIONS: Comparing data on neuropsychological recovery from AUD will improve understanding of the impact of alcohol on the brain, and the relationship between AUD recovery and quality of life/treatment outcomes. It may provide information that could one day inform aspects of treatment and aftercare (e.g., options for cognitive training of functions that do not improve on their own).

The Effect of Think Aloud on Performance and Brain Oxygenation During Cycling - An Exploratory Study.

In this study, we aimed to investigate the effect of Think Aloud (TA) on performance in trained and untrained participants, using functional Near Infrared Spectroscopy, during incrementally paced cycling. A mixed design was implemented with cycling expertise (10 untrained vs. 9 trained) as the between groups variable and trial stage (5 stages of increasing effort), and condition (silent vs. TA) as within groups independent variables (IVs). Dependent measures were changes in cortical oxygenation (O2Hb) in 12 areas of the prefrontal cortex (PFC) and physiological indicators of percentage heart rate maximum (%HRmax), average power output (APO), peak power output (PPO), rate of perceived exertion (RPE) and blood lactate ([La]b) over time. Trained cyclists had higher APO and significantly higher PPO from stages 2-5, in addition to a greater increase in PPO over the duration of the test (range 168W-480 W vs. 133W-313 W). There were significant main effects of stage on %HRmax, Bla and RPE (p < .001), with effect sizes (ήp2) ranging from .31 to .97. On average, HRmax%, [La]b and RPE were significantly lower after stage 2 onwards within the TA trial than the silent trial, even though similar power outputs were obtained. Thus, the TA trial elicited a better pacing strategy. There was no main effect of group on changes in O2Hb, though O2Hb did change as a function of stage in four areas of the PFC, and as a function of condition in one area. In this first study to assess the effects of TA on performance during self-paced cycling, TA did not disrupt performance outcomes at low through to high levels of physical exertion for either untrained or trained participants.

Neurological and cognitive alterations induced by MDMA in humans.

3,4 Methylenedioxymethamphetamine generally referred to as MDMA or 'ecstasy' is a ring-substituted phenethylamine stimulant which produces powerful empathogenic effects. Use of MDMA remains popular despite prohibition, and potential long-term negative consequences of repeated use. MDMA produces its acute subjective effects primarily by stimulating the release of serotonin via action at the serotonin transporter (SERT). There is evidence that MDMA administration may lead to long lasting neurotoxic effects on serotonin neurons in primates, and reductions in markers of central serotonin axons, and axon terminals in animals. In humans, demonstration of serotonergic neurotoxicity is much more difficult to identify, and much of the research is complicated by confounding issues of polysubstance use, genetic and environmental factors and reliance on self-reports of previous drug use. We do not review the mechanisms for neurotoxicity in detail as they are covered elsewhere in this special issue. There is a large body of literature, however, which has investigated potential cognitive and neurocognitive consequences of repeated MDMA use. Here we review the literature on cognition, and neuroimaging studies that have investigated structural and functional brain changes associated with ecstasy use.

Subjective executive function deficits in hazardous alcohol drinkers.

BACKGROUND: Dependent alcohol drinkers exhibit differences in the structure and function of the brain, and impairments in cognitive function, including executive functions (EFs). Less is known about the impact of non-dependent but hazardous use (that which raises the risk of harm), and it is also unclear to what extent executive impairments in this cohort affect real-world function. The current study examines the relationship between alcohol use, EF and alcohol-related problems, in the general population. METHODS: A between-groups cross-sectional design assessed EF across two levels of drinking; hazardous (Alcohol Use Disorders Identification Test (AUDIT) score of ⩾8) and non-hazardous. Alcohol drinkers (n = 666; 136 male; 524 female; six not disclosed; aged 28.02 ± 10.40 years) completed validated questionnaires online assessing subjective EF, alcohol use and alcohol-related problems. RESULTS: Organisation, Strategic Planning, Impulse Control and overall function were significantly impaired in hazardous drinkers. Furthermore, the effect of alcohol on EF, partially mediated the relationship between alcohol use and alcohol-related problems. CONCLUSION: Hazardous drinking was associated with lower subjective EF, and this mediated the effect of alcohol on alcohol-related problems. This may be due to changes in prefrontal brain regions, which could indicate greater risk for the development of alcohol dependence (AD). Future research should use additional means to assess EF in hazardous drinkers, including recovery of function, development of AD and the relationship between cognition and alcohol-related daily problems.

A pilot study assessing the brain gauge as an indicator of cognitive recovery in alcohol dependence.

Alcohol dependence (AD) is associated with multiple cognitive deficits, which can affect treatment outcomes. Current measures of tracking brain recovery (e.g., functional magnetic resonance imaging) can be less accessible for practitioners. This study pilots a novel device (the brain gauge; BG) to assess its utility, and track recovery of cognitive function in residential alcohol treatment. METHODS: A repeated measures design assessed changes in cognitive function during detoxification. Twenty-one participants with AD (16 Male; Mean age 43.85 ± 6.21) completed a battery of alcohol and memory questionnaires and BG tasks at two time-points (∼days 4 and 10) during a single managed detoxification episode. RESULTS: Repeated measures ANCOVA revealed that some BG metrics significantly improved, with medium to large effect sizes - processing speed, focus, temporal order judgement and overall cortical metric. However, differences in subjective cognitive function were non-significant after controlling for depression and anxiety change scores. Anxiety change emerged as a significant factor in subjective cognitive function. CONCLUSIONS: We conclude it is possible that the prefrontal cortex (PFC) recovers more slowly compared to other brain areas, and there are compounding effects of improvements in anxiety and depression, and metacognitive deficits on subjective EF assessments. Future research should seek to validate the clinical utility of the BG by comparing against established neuroimaging methods.

Age-related prefrontal cortex activation in associative memory: An fNIRS pilot study.

Older adults typically perform more poorly than younger adults in free recall memory tests. This age-related deficit has been linked to decline of brain activation and brain prefrontal lateralization, which may be the result of compensatory mechanisms. In the present pilot study, we investigated the effect of age on prefrontal cortex (PFC) activation during performance of a task that requires memory associations (temporal vs. spatial clustering), using functional Near-Infrared Spectroscopy (fNIRS). Ten younger adults, ten cognitively high-performing older individuals, and ten low-performing older individuals completed a free recall task, where either a temporal or spatial strategy (but not both simultaneously) could be employed to retrieve groups of same-category stimuli, whilst changes in PFC hemodynamics were recorded by means of a 12-channel fNIRS system. The results suggest PFC activation, and right lateralization specific to younger adults. Moreover, age did not affect use of memory organization, given that temporal clustering was preferred over spatial clustering in all groups. These findings are in line with previous literature on the aging brain and on temporal organization of memory. Our results also suggest that the PFC may be specifically involved in memory for temporal associations. Future research may consider whether age-related deficits in temporal organization may be an early sign of PFC pathology and possible neurodegeneration.

How effective are pharmaceuticals for cognitive enhancement in healthy adults? A series of meta-analyses of cognitive performance during acute administration of modafinil, methylphenidate and D-amphetamine.

Modafinil, methyphenidate (MPH) and d-amphetamine (d-amph) are putative cognitive enhancers. However, efficacy of cognitive enhancement has yet to be fully established. We examined cognitive performance in healthy non-sleep-deprived adults following modafinil, MPH, or d-amph vs placebo in 3 meta-analyses, using subgroup analysis by cognitive domain; executive functions (updating, switching, inhibitory control, access to semantic/long term memory), spatial working memory, recall, selective attention, and sustained attention. We adhered to PRISMA. We identified k = 47 studies for analysis; k = 14 studies (64 effect sizes) for modafinil, k = 24 studies (47 effect sizes) for Methylphenidate, and k = 10 (27 effect sizes) for d-amph. There was an overall effect of modafinil (SMD=0.12, p=.01). Modafinil improved memory updating (SMD=0.28, p=.03). There was an overall effect of MPH (SMD=0.21, p=.0004) driven by improvements in recall (SMD=0.43, p=.0002), sustained attention (SMD=0.42, p=.0004), and inhibitory control (SMD=0.27, p=.03). There were no effects for d-amph. MPH and modafinil show enhancing effects in specific sub-domains of cognition. However, data with these stimulants is far from positive if we consider that effects are small, in experiments that do not accurately reflect their actual use in the wider population. There is a user perception that these drugs are effective cognitive enhancers, but this is not supported by the evidence so far.

Is (poly-) substance use associated with impaired inhibitory control? A mega-analysis controlling for confounders.

Many studies have reported that heavy substance use is associated with impaired response inhibition. Studies typically focused on associations with a single substance, while polysubstance use is common. Further, most studies compared heavy users with light/non-users, though substance use occurs along a continuum. The current mega-analysis accounted for these issues by aggregating individual data from 43 studies (3610 adult participants) that used the Go/No-Go (GNG) or Stop-signal task (SST) to assess inhibition among mostly "recreational" substance users (i.e., the rate of substance use disorders was low). Main and interaction effects of substance use, demographics, and task-characteristics were entered in a linear mixed model. Contrary to many studies and reviews in the field, we found that only lifetime cannabis use was associated with impaired response inhibition in the SST. An interaction effect was also observed: the relationship between tobacco use and response inhibition (in the SST) differed between cannabis users and non-users, with a negative association between tobacco use and inhibition in the cannabis non-users. In addition, participants' age, education level, and some task characteristics influenced inhibition outcomes. Overall, we found limited support for impaired inhibition among substance users when controlling for demographics and task-characteristics.

MDMA and brain activity during neurocognitive performance: An overview of neuroimaging studies with abstinent 'Ecstasy' users.

MDMA/Ecstasy has had a resurgence in popularity, with recent supplies comprising higher strength MDMA, potentially leading to increased drug-related harm. Neurocognitive problems have been widely reported in ecstasy users, equally some studies report null findings, and it remains unclear which factors underlie the development of neurocognitive impairments. This review covers the empirical research into brain activity during neurocognitive performance, using fMRI, fNIRS, and EEG. Our main conclusion is that chronic repeated use of recreational ecstasy can result in haemodynamic and electrophysiological changes that reflect recruitment of additional resources to perform cognitive tasks. Findings are consistent with serotonergic system changes, although whether this reflects neurotoxicity or neuroadaptation, cannot be answered from these data. There is a degree of heterogeneity in the methodologies and findings, limiting the strengths of current conclusions. Future research with functional neuroimaging paired with molecular imaging, genetics or pharmacological challenges of the serotonin system may help to decipher the link between serotonergic and cognitive changes in ecstasy users.