Memory performance in abstinent 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") users

Research with animals and humans has suggested that acute and subacute use of 3,4-methylenedioxymethamphetamine (MDMA "ecstasy") may lead to memory impairment. However, research is limited by (1) low power due to small sample sizes, (2) the possible confound of polydrug use, and (3) the failure to consider intelligence as a covariate. The present study compared the memory performance on the Wechsler Memory Scale-III of 26 abstinent (2-wk. minimum) recreational MDMA users with 26 abstinent (2-wk. minimum) recreational polydrug users. Despite significantly greater polydrug use amongst these MDMA users, no significant group differences in memory were observed. Regression of total lifetime amount of MDMA use also did not predict memory performance after accounting for intelligence. In addition, the length of time since abstinence (at least 2 wk.) was not associated with an increase in memory performance. Greater total lifetime cocaine use, rather than total lifetime MDMA use, was significantly associated with greater decrements in General Memory and Delayed Verbal Memory performance.     

The effects of binge MDMA on acquisition and reversal learning in a radial-arm maze task

The current study used the partially-baited radial-arm maze paradigm to study the effects of a single-treatment high-dose exposure ('binge') to MDMA (± 3,4-methylenedioxymethaphemtamine or 'Ecstasy') on memory task acquisition. Sprague-Dawley rats were administered a binge dose (4 × 10 mg/kg) of MDMA and their ability to subsequently acquire the radial-arm maze task was compared against saline controls. The MDMA-treated rats were significantly slower to learn the task and made more reference memory errors than the controls. Working memory function was found to be relatively unimpaired. Following a reversal of task rules the MDMA-treated rats were again significantly slower to acquire the appropriate rule despite having eventually achieved a similar level of overall performance as control rats. However evidence of drug tolerance was found when all rats were challenged with an acute low dose of MDMA (1 × 4.0 mg/kg) because the binge MDMA rats were relatively less impaired. Therefore, although binge treated MDMA rats were able to achieve very accurate performance equivalent to the controls they took significantly longer to do this and were less able to adapt their behavior to a change in task rules. In addition the binge treated MDMA rats displayed tolerance to acute MDMA exposure. These findings are consistent with the possibility that human Ecstasy users may show deficits in acquiring information and may experience deficits in cognitive flexibility as well as developing tolerance to the drug with repeated exposure.     

Personality scores and licit and illicit substance use

The effects of personality structure on subsequent substance use was examined. Data were collected from 841 men from Zürich questioned twice at the age of 19 and 22 about drug use and personality. Multiple regression and canonical correlation analysis methodology indicated a significant relationship between personality and subsequent substance use. Illicit drug consumption was positively related to the personality scale Depressiveness and negatively to Dominance and Excitability, cigarette consumption correlated with Nervousness and Sociability and alcohol consumption was related to Nervousness, Depressiveness and Sociability. The association of illicit drug use with Emotional Lability decreased when cigarette and alcohol consumption was included in the analysis. The cannabis users described themselves less neurotic than the consumers of alcohol and cigarettes.     

Changes in cannabis use in emerging adulthood: The influence of peer network,impulsivity, anxiety and depression

IntroductionCannabis is the most commonly used illicit drug with the highest prevalence reported among 15- to 24-year-olds. This specific period of emerging adulthood constitutes a critical age for substance use and for future consumption. Cannabis use patterns change during college or university and the post-college transition; users are at greater risk of adverse health outcomes (especially if they start or maintain a pattern of frequent use).ObjectivesThe overall aim of this study was to highlight psychological and relational factors that might be associated with changes (including cessation and fluctuation) in cannabis use during this specific period, separately for males and females.MethodsThe subjects were 682 first-year college students (69.94% of female), aged between 18 and 25 years (M = 18.59 years, SD = 1.56). Four groups were formed according to cannabis consumption: “non-users” (54.64%), “desisting users” (14.04%), “fluctuating users” (16.23%), and “persistent users” (15.07%). A self-report questionnaire was administered to evaluate prevalence, frequency and trajectory of use, number of peer cannabis users, alcohol use, impulsivity, anxiety (trait and social) and depression.ResultsFemales appear more sensitive to the romantic partner's consumption than males. For both sexes, having more friends who use cannabis appears to be a determinant. Depression and anxiety were not related to changes in cannabis use. Impulsivity is a significant factor for the maintenance of cannabis use in emerging adulthood, with higher lack of premeditation for males and higher sensation seeking for females among fluctuating and persistent users.ConclusionsResults are discussed in terms of maintenance of use and the spiral of consumption, including clinical implications for prevention and interventions.     

Substance use and abuse among children and teenagers

During the past several years, there has been a renewed national concern about drug abuse, culminating in the current "war on drugs." In this review, we emphasize that even though child or teenage drug use is an individual behavior, it is embedded in a sociocultural context that strongly determines its character and manifestations. Our focus is on psychoactive substances both licit (cigarettes and alcohol) and illicit (e.g., cannabis and cocaine). We feel that it is critical to draw a distinction between use and abuse of drugs and to do so from a multidimensional perspective that includes aspects of the stimulus (drug), organism (individual), response, and consequences. Our selective review of substance use and abuse among children and adolescents covers epidemiology (patterns and extent of drug use), etiology (what generates substance use), prevention (how to limit drug use), treatment (interventions with drug users), and consequences (effects and outcomes of youthful drug use).     

The short-term consequences of early onset cannabis use

The associations between early onset (prior to 15 years of age) cannabis use and rates of mental health or adjustment problems during the period from 15 to 16 years of age were studied in a New Zealand birth cohort. Early onset cannabis users were at increased risks of later substance use behaviors, conduct/oppositional disorders, juvenile offending, severe truancy, school dropout, anxiety, depression, and suicidal ideation. Early cannabis users had odds of these outcomes ranging from 2.7 to 30.8 times higher than the odds for those who did not use cannabis prior to age 15. Most of the elevated risks of early onset users were explained by the fact that they were a high-risk group of adolescents characterized by family disadvantages, early adjustment problems, and high affiliations with substance-using or delinquent peers. Nonetheless, even after adjustment for a wide range of confounding factors, early onset users had increased risks of later cannabis use. It is concluded that while most of the elevated risks of early onset users were explained by social, family, and individual characteristics of this group, early onset users were at increased risks of later cannabis use.This research was funded by grants from the Health Research Council of New Zealand, the National Child Health Research Foundation and the Canterbury Medical Research Foundation.     

Weighing the Evidence: A Systematic Review on Long-Term Neurocognitive Effects of Cannabis Use in Abstinent Adolescents and Adults

Findings on neurocognitive effects of sustained cannabis use are heterogeneous. Previous work has rarely taken time of abstinence into account. In this review, we focus on understanding sustained effects of cannabis, which begin when clinical symptoms of the drug have worn off after at least 14 days. We conducted a search between 2004 and 2015 and found 38 studies with such a prolonged abstinence phase. Study-design quality in terms of evidence-based medicine is similar among studies. Studies found some attention or concentration deficits in cannabis users (CU). There is evidence that chronic CU might experience sustained deficits in memory function. Findings are mixed regarding impairments in inhibition, impulsivity and decision making for CU, but there is a trend towards worse performance. Three out of four studies found evidence that motor function remains impaired even after a time of abstinence, while no impairments in visual spatial functioning can be concluded. Functional imaging demonstrates clear differences in activation patterns between CU and controls especially in hippocampal, prefrontal and cerebellar areas. Structural differences are found in cortical areas, especially the orbitofrontal region and the hippocampus. Twenty studies (57 %) reported data on outcome effects, leading to an overall effect size of r _mean?=?.378 (CI 95 %?=?[.342; .453]). Heavy use is found to be more consistently associated with effects in diverse domains than early age of onset. Questions of causality―in view of scarce longitudinal studies, especially those targeting co-occurring psychiatric disorders―are discussed.     

Personality characteristics as a function of frequency and type of substance use

Problematic and unhealthy personality characteristics have typically been the focus of researchers interested in the possible causes of substance use/abuse. Recent research has begun to identify differences between individuals based upon frequency of use, with indications that moderate users may have "healthier" characteristics than either abstainers or regular users. The present study was conducted in a rural setting and compared personality structure (based on the California Psychological Inventory) among three groups of college students: abstainers, experimenters, and regular users. The comparisons were conducted as a function of all illicit substance use (excluding alcohol) and for alcohol use only. Minimal support was obtained for the above hypothesis when comparing the three groups on illicit substance use. When comparing the three groups on alcohol use only, support for the theory was identified, with fewer differences found between the experimenters and the abstainers than between the experimenters and the regular users. It is suggested that rural use of psychoactive substances may be more limited to alcohol due to easier availability and less stigma. Data supporting the "healthier" personality structure of moderate users of alcohol would thus be more likely in rural settings even though such use would still be "risky" behavior given its illegality for individuals under age 21. The need for adaptations to current treatment approaches is suggested.     

Effects of cannabis on eyewitness memory: A field study

Eyewitnesses to crimes are regularly under the influence of drugs, such as cannabis. Yet there is very little research on how the use of cannabis affects eyewitness memory. In the present study, we assessed the effects of cannabis on eyewitness recall and lineup identification performance in a field setting. One hundred twenty visitors of coffee shops in Amsterdam viewed a videotaped criminal event, were interviewed about the event, and viewed a target‐present or target‐absent lineup. Witnesses under the influence of cannabis remembered significantly fewer correct details about the witnessed event than did sober witnesses, with no difference in incorrect recall. Cannabis use was not significantly associated with lineup identification performance, but intoxicated witnesses were significantly better at judging whether their lineup identification was accurate. Theoretical and practical implications of the findings are discussed.     

Substance use risk across three generations: the roles of parent discipline practices and inhibitory control.

This study used 3 generations and 21 years of prospective data to test models of intergenerational transmission of substance use and substance use risk. Thus, the study extends prior studies in the field that have focused predominantly on substance abuse. The association between the grandparental generation's (G1 mother and father) and the parental generation's (G2 father) alcohol use and illicit drug use was hypothesized to be mediated by G2's poor inhibitory control. Additionally, G1's poor discipline of G2 was hypothesized to be directly associated with G2's substance use as well as to partially mediate the association between G1's substance use and G2's inhibitory control. In turn, G2's substance use in late adolescence was expected to be associated with its offspring's (G3) poor inhibitory control at age 3 years. Findings partially supported the predictions and varied by substance. For alcohol use, only cross-generational associations in use were found. For illicit drugs, both poor inhibitory control and poor discipline played some mediational role in cross-generational use.     

Evidence for executive deficits among users of MDMA (Ecstasy)

Random letter generation and computation span are tasks known to load on executive, prefrontal resources. Previous research suggests that Ecstasy users are impaired on random letter generation. The current study, employing a larger sample (44 current Ecstasy users, and 59 non‐Ecstasy users), together with more effective statistical controls for other drug use, failed to replicate previous findings. Ecstasy users were unimpaired on all measures of random generation performance. A significant difference was obtained on the computation span measure, with Ecstasy users scoring significantly lower than non‐Ecstasy users. This difference remained statistically significant following control for various indicators of the use of other drugs including cannabis. The results are discussed in terms of the potential effects that Ecstasy might have on different component executive processes.     

An examination of the relationships between cannabis use,driving under the influence of cannabis and risk-taking on the road

IntroductionSome studies have suggested that regular cannabis users appear to exhibit a general reckless driving style that may contribute to an inflated estimate of collisions related to driving under the influence of cannabis (DUIC) among this group.ObjectiveThis study investigated whether patterns of cannabis use would predict levels of self-reported unsafe driving behaviours and levels of performance observed in a driving simulator.MethodThe study investigated 48 young cannabis users with respect to frequency of cannabis consumption, alcohol use, driving exposure, self-reported dangerous driving habits, impulsivity, sensation seeking and performance in a driving simulator.ResultsCannabis use was positively associated with DUIC, with sensation seeking and with self-reports of risky driving. An ANOVA confirmed a significant effect of levels of consumption of cannabis among participants on self-report risk-taking in driving. Moreover, the observed behaviours during the simulation tasks correlated with risky driving habits, and with the self-reported frequency of driving in the hour following smoking cannabis or immediately after drinking alcohol.ConclusionSince cannabis usage and DUIC appear to be related to an overall reckless style of driving, it is proposed that public safety policies should be more holistic, simultaneously targeting multiple on-road dangerous behaviours for intervention.     

Childhood predictors of adolescent substance use in a longitudinal study of children with ADHD

Children diagnosed with attention-deficit/hyperactivity disorder (ADHD; n = 142) were prospectively monitored into adolescence (13-18 years old) to evaluate their risk for elevated substance use relative to same-aged adolescents without ADHD (n = 100). Probands reported higher levels of alcohol, tobacco, and illicit drug use than did controls. Group differences were apparent for alcohol symptom scores but not for alcohol or marijuana disorder diagnoses. Within probands, severity of childhood inattention symptoms predicted multiple substance use outcomes: childhood oppositional defiant disorder/conduct disorder (ODD/CD) symptoms predicted illicit drug use and CD symptoms. Persistence of ADHD and adolescent CD were each associated with elevated substance use behaviors relative to controls. Further study of the mediating mechanisms that explain risk for early substance use and abuse in children with ADHD is warranted.     

Construct Validity of the Balloon Analogue Risk Task (BART): Relationship with MDMA Use by Inner-City Drug Users in Residential Treatment

In a program of research assessing the validity of the balloon analogue risk task (BART; C. W. Lejuez et al., 2002) as a measure of risk taking, the BART was administered to a sample of inner-city drug users in residential treatment (n = 76). Construct validity of the BART was evaluated by measuring risk-taking behavior and 3,4-methylenedioxymethamphetamine (MDMA) use while controlling for self-reported impulsivity, sensation seeking, polysubstance use, and demographic variables. Supporting the construct validity of the BART, while controlling for interrelated variables in the context of logistic regression analyses, (BART) risk-taking propensity accounted for significant incremental variance in differentiating MDMA users from non-users. BART scores, polysubstance use, and younger age were most associated with MDMA use, and together these variables were associated with 91% classification accuracy in predicting MDMA use.     

Effects of homophobic name‐calling and verbal sexual harassment on substance use among young adults

Verbal aggression victimization, such as homophobic name‐calling, has been linked to heavier substance use among young people, but little longitudinal research has examined how different types of victimization may affect substance use or whether certain psychosocial factors moderate these risks. In a diverse cohort (N = 2,663), latent transition analysis was used to model heterogeneity in victimization (age 19) and substance use (age 20). Four victimization (high victimization, homophobic name‐calling only, verbal sexual harassment only, and low victimization) and three substance use (poly‐substance use, alcohol, and cannabis only, low all) classes were identified. The high victimization and homophobic name‐calling only classes had the highest probabilities of transitioning into the poly‐substance use class, and the high victimization class had the highest probability of transitioning into the alcohol and cannabis only class. The probability of transitioning into the low all substance use class was highest in the low victimization class and lowest in the high victimization class. For the high victimization class, greater depressive symptoms increased the odds, and better peer relationship quality decreased the odds, of transitioning into the poly‐substance use and alcohol and cannabis only classes. For the homophobic name‐calling only class, greater depressive symptoms increased the odds of transitioning into the poly‐substance use class. Homophobic name‐calling, alone or in combination with verbal sexual harassment, is a risk factor for escalating substance use in young adulthood, especially among victims with depressive symptoms.     

Reasons for substance use among people with psychotic disorders: method triangulation approach

Substance use disorders (SUD) are common among people with psychotic disorders and are associated with many negative consequences. Understanding the reasons for substance use in this population may allow for the development of more effective prevention and intervention strategies. We examined reasons for tobacco, alcohol, or cannabis use among people with psychotic disorders. Sixty-four participants with a diagnosed psychotic disorder completed a self-report reasons for use questionnaire. A subset of eight participants completed semi-structured qualitative interviews. Both the qualitative and quantitative data indicated that reasons for use of tobacco, alcohol, and cannabis differed considerably. Tobacco was primarily used for coping motives, alcohol for social motives, and cannabis for pleasure enhancement motives. Prevention and intervention strategies targeting coexisting psychotic disorders and SUD may improve in effectiveness if they address the perceived beneficial effects of tobacco use, the strong social pressures influencing alcohol use and if they encourage cannabis users to seek alternative pleasurable activities.     

Age benefits in everyday prospective memory: the influence of personal task importance, use of reminders and everyday stress

The present diary study examined everyday prospective memory tasks in younger and old adults and explored the role of personal task importance, use of reminders and everyday stress as possible correlates of age-related prospective memory performance in everyday life. Results revealed an age benefit in everyday prospective memory tasks. In addition, task importance was identified as a critical moderator of age-related prospective memory performance. More frequent use of reminders and lower levels of stress, however, were associated with better prospective memory performance in general but did not contribute to age-related prospective memory performance. Exploring further possible correlates of prospective memory revealed that the strategy to reprioritize initially planned intentions was associated with age benefits in everyday prospective memory. Results suggest that the age-related benefit observed in experimenter-given tasks transfers to everyday prospective memory and varies in dependence of motivational and cognitive factors. Implications for theoretical models of prospective memory and aging are discussed.     

Threat-related processing supports prospective memory retrieval for people with obsessive tendencies

Obsessive-compulsive disorder can result in a variety of deficits to cognitive performance, including negative consequences for attention and memory performance. The question addressed in the current study concerned whether this disorder influenced performance in an event-based prospective memory task. The results from a subclinical population indicated that, relative to non-anxious controls and mildly depressed controls, people with obsessive-compulsive tendencies (washing compulsions) incur decrements in remembering to respond to cues related to a neutral intention (respond to animals). This deficit was ameliorated by giving the subclinical group an intention about a threat-related category (respond to bodily fluids) and cueing them with concepts that they had previously rated as particularly disturbing to them. Thus, their normal attentional bias for extended processing of threat-related information overcame their natural deficit in event-based prospective memory.     

Patterns of substance use in early through late adolescence

This study examined patterns of substance use throughout adolescence. A cluster analytic approach was used to identify subgroups of adolescents on the basis of their levels of substance use from early through late adolescence (Grades 6 through 11). Six distinct clusters of substance users emerged—2 groups representing relatively stable patterns of substance use from early through late adolescence (i.e., nonusers and alcohol experimenters), and 4 groups of users showing escalating patterns of substance use (i.e., low escalators, early starters, late starters, and high escalators). The study provides a comprehensive view of adolescent substance use by examining the progression of use from early to late adolescence, demonstrates the usefulness of studying patterns of use across multiple substances, and underscores the importance of building classification schemes based on repeated measurements of substance use to reflect changes over time. Implications of the findings for future research and for identifying high-risk subgroups of adolescents for purposes of intervention based on timing and pattern of escalation are discussed.     

Relationships Between Dimensions of Impulsivity and Prospective Memory

Prospective memory refers to the ability to plan and execute future intentions. A burgeoning body of research indicates that a significant proportion of the variability in prospective memory performance can be accounted for by personality traits, with two recent studies revealing that the various dimensions of impulsivity measured by the Barratt Impulsivity Scale‐11 (BIS‐11) are related to prospective memory failures. The present study was conducted to examine which dimensions of impulsivity indexed by the BIS‐11 and UPPS‐P relate to prospective memory failures and which dimensions of impulsivity contribute unique variance in the prediction of prospective memory failures. A large sample (N = 662) of students completed the BIS‐11, UPPS‐P, Prospective Memory Questionnaire and a habitual prospective memory test. Consistent correlations between six of the seven measures of impulsivity and prospective memory failures were found. Regression analyses further revealed that lack of perseverance, emotional urgency and attentional impulsivity were reliable and unique predictors of prospective memory failures. Thus, difficulty remaining focused on tasks (especially long, boring or difficult tasks); lack of forethought, planning and distaste for challenging tasks; and tendencies to behave impulsively under conditions of strong affect relate most strongly to prospective memory failures. Copyright © 2015 European Association of Personality Psychology