humulene and Memory-Disorders

Cannabis is an illegal drug whose use has increased in recent years, especially among adolescents. Despite its popularity, its use and abuse brings with it health consequences, being greater if consumption occurs in the adolescent stage, since the brain is in full development. The objective of this systematic review was to determine the effects of cannabis use on cognitive functions of attention and memory in adolescent population.. A systematic review of the literature was carried out in the main search portals (Pubmed, Web of Science, SciELO, Cochrane) referring to the last 10 years, following the PRISMA criteria. The systematic search strategy was carried out in the period from March to May 2021, applying the PICO method and the PEDro scale to guarantee the methodological quality of the included studies.. Both attention and memory are affected by cannabis use; however, memory functions improve with abstinence, not being so for attention. Memory deficits are an indicator of therapeutic abandonment of addiction treatment. In relation to psychosocial interventions aimed at improving memory, the contingency management, educational interventions and motivational interviewing have not been shown to be effective on the effects of substances. Working memory training offers positive results, although not clinically significant. Finally, memory deficits are an indicator of therapeutic abandonment of pharmacological treatment for cannabis addiction. Therefore, research is needed aimed both at reducing the side effects of drugs on memory processes and at establishing to what extent memory deficits associated with cannabis use can facilitate therapeutic abandonment.. More research is necessary, considering the dual consumption of cannabis-tobacco and the effects that both substances may have jointly and separately on attention and memory processes.. El cannabis es una droga ilegal cuyo consumo se ha visto incrementado en los últimos años, especialmente en población adolescente. A pesar de su popularidad, su uso y abuso trae consigo consecuencias para la salud, siendo mayores si el consumo se produce en la etapa adolescente, ya que el cerebro se encuentra en pleno desarrollo. El objetivo de esta revisión sistemática fue determinar los efectos del consumo de cannabis en las funciones cognitivas de atención y memoria en población adolescente.. Se llevó a cabo una revisión sistemática de la literatura en los principales portales de búsqueda (. Tanto la atención como la memoria se ven afectadas por el consumo de cannabis; sin embargo, la memoria mejora su funcionamiento con la abstinencia, no ocurriendo lo mismo con la atención. Los déficits de memoria son un indicador de abandono terapéutico del tratamiento para la adicción. En relación con las intervenciones psicosociales orientadas a la mejora de la memoria, tanto el manejo de contingencias como las intervenciones educativas y la entrevista motivacional no se han mostrado efectivas sobre los efectos de las sustancias. El entrenamiento en la memoria de trabajo ofrece resultados positivos, aunque clínicamente no significativos. Finalmente, los déficits de memoria son un indicador de abandono terapéutico del tratamiento farmacológico para la adicción al cannabis, por lo que se precisa investigación orientada tanto a reducir los efectos secundarios de los fármacos sobre los procesos mnésicos como a establecer en qué medida los déficits de memoria asociados al consumo de cannabis pueden facilitar el abandono terapéutico.. Se precisa mayor investigación, considerando el consumo dual de cannabis-tabaco y los efectos que ambas sustancias pueden tener, conjuntamente y por separado, sobre los procesos de atención y memoria.

Topics: Adolescent; Cannabis; Humans; Illicit Drugs; Marijuana Abuse; Memory Disorders; Spain

There are no recent reports summarising the magnitude of prospective memory (PM) impairments in recreational drug users.. We performed a meta-analysis of studies (with a parallel group design) examining PM performance in users of common recreational drugs (including alcohol and tobacco) who were not intoxicated during testing. Studies were also evaluated for the presence of methodological bias.. Twenty-seven studies were included in the meta-analysis following literature searches of MEDLINE, EMBASE and PsycINFO. Effect sizes (standardised mean difference; SMD) were calculated separately for the effects of alcohol, cannabis, ecstasy, methamphetamine and tobacco use. The influences of drug use and study characteristics on effect sizes were explored using meta-regressions. Sources of study bias were also assessed.. Heavy drinkers and regular drug users tended to perform worse than controls on event and time-based PM tasks. Effect sizes (standardised mean differences; SMDs) for event-based PM impairment across the different drug-using groups/heavy drinkers ranged between - 1.10 and - 0.49, with no 95% CI crossing 0.00. SMDs for time-based PM ranged between - 0.98 and - 0.70. Except for the CIs associated with the ES for smokers' time-based PM performance, no CIs crossed 0.00.. Although all drug-using groups showed moderate-large impairments in event and time-based PM, effect sizes had low precision and moderate-high levels of heterogeneity. In addition, several methodological and reporting issues were identified in the majority of studies. As such, considerable uncertainty remains regarding the role of confounds and the magnitude of PM impairments in non-intoxicated recreational drug users.

Topics: Alcohol Drinking; Cannabis; Hallucinogens; Humans; Illicit Drugs; Memory Disorders; Memory, Episodic; N-Methyl-3,4-methylenedioxyamphetamine; Substance-Related Disorders

Heavy cannabis use has been frequently associated with increased rates of mental illness and cognitive impairment, particularly amongst adolescent users. However, the neurobiological processes that underlie these associations are still not well understood. In this review, we discuss the findings of studies examining the acute and chronic effects of cannabis use on the brain, with a particular focus on the impact of commencing use during adolescence. Accumulating evidence from both animal and human studies suggests that regular heavy use during this period is associated with more severe and persistent negative outcomes than use during adulthood, suggesting that the adolescent brain may be particularly vulnerable to the effects of cannabis exposure. As the endocannabinoid system plays an important role in brain development, it is plausible that prolonged use during adolescence results in a disruption in the normative neuromaturational processes that occur during this period. We identify synaptic pruning and white matter development as two processes that may be adversely impacted by cannabis exposure during adolescence. Potentially, alterations in these processes may underlie the cognitive and emotional deficits that have been associated with regular use commencing during adolescence.

Topics: Adolescent; Animals; Brain; Cannabinoids; Cannabis; Depression; Endocannabinoids; Female; Humans; Learning Disabilities; Memory Disorders; Pregnancy; Prenatal Exposure Delayed Effects; Schizophrenia

This article reviews neuropsychological performance in frequent users of cocaine, (meth)amphetamines, ecstasy, opiates, alcohol, and cannabis. We searched the scientific literature published in the last five years, focusing on studies that required at least 2 weeks of abstinence from drug use, and included a control group. All substances of abuse, except cannabis, were associated with sustained deficits in executive functioning, especially inhibition. In addition, verbal memory decrements were consistently found in cocaine, (meth)amphetamines and ecstasy users, but not in heroin or cannabis users. More specific executive functioning deficits were reported depending on the substance of abuse. Cocaine was associated with diminished cognitive flexibility, whereas (meth)amphetamines were associated with worse cognitive planning functions compared to controls. Opiate studies showed lower scores on verbal fluency in opiate dependent subjects compared to controls. Working memory and visuospatial abilities were compromised in alcohol abusers. In ecstasy users, inconsistent findings have been reported across neuropsychological domains, with the exception of inhibition and verbal memory. There was little evidence for sustained cognitive impairments in adult abstinent cannabis users. Recognition of neuropsychological problems related to different substances can help to select subjects that will benefit most from treatment. Furthermore, a better understanding of the neuropsychological impairments in drug abusing individuals could help to explain the remitting course of substance abuse disorders and to improve psychological interventions.

Topics: Alcoholism; Amphetamine-Related Disorders; Cannabis; Central Nervous System Stimulants; Cocaine; Cocaine-Related Disorders; Drug Users; Hallucinogens; Heroin Dependence; Humans; Marijuana Abuse; Memory Disorders; Methadone; Methamphetamine; N-Methyl-3,4-methylenedioxyamphetamine; Neuropsychological Tests; Opioid-Related Disorders; Psychomotor Performance; Recognition, Psychology; Substance-Related Disorders; Verbal Behavior

A meta-analysis was conducted to examine the impact of recreational ecstasy use on short-term memory (STM), long-term memory (LTM), verbal and visual memory. We located 26 studies containing memory data for ecstasy and non-ecstasy users from which effect sizes could be derived. The analyses provided measures of STM and LTM in 610 and 439 ecstasy users and revealed moderate-to-large effect sizes (Cohen's d) of d = -0.63 and d = -0.87, respectively. The difference between STM versus LTM was non-significant. The effect size for verbal memory was large (d = -1.00) and significantly larger than the small effect size for visual memory (d = -0.27). Indeed, our analyses indicate that visual memory may be affected more by concurrent cannabis use. Finally, we found that the total lifetime number of ecstasy tablets consumed did not significantly predict memory performance.

Topics: Cannabis; Databases, Factual; Hallucinogens; Humans; Illicit Drugs; Memory Disorders; Memory, Short-Term; Mental Recall; N-Methyl-3,4-methylenedioxyamphetamine; Neuropsychological Tests; Substance-Related Disorders

Drug models of mental illness are considered useful if they provoke its characteristic symptoms. In this respect, ketamine and tetrahydrocannabinol (cannabis) are coming under increasing scrutiny as models for schizophrenia. However, although both undoubtedly produce psychotic symptoms characteristic of the disorder, we argue here that, because schizophrenia is also accompanied by cognitive deficits, a full understanding of the impact of these drugs on cognition will be crucial in taking these models further. Memory deficits are pronounced in schizophrenia and we focus upon patterns of working and episodic memory impairment produced by ketamine and cannabis, identifying overlaps between drug and illness. We suggest that close attention to these deficits can offer insights into core pathophysiology of schizophrenia.

Topics: Age Factors; Animals; Attention; Cannabis; Evoked Potentials; Humans; Ketamine; Memory Disorders; Memory, Short-Term; Schizophrenia

In 1984, I published in this journal a review entitled "Marijuana: A Crude Drug With a Spectrum of Underappreciated Toxicity." In the introduction to that article, I disclosed that our son Keith, who was 15 years old at the time, was in a long-term, modified outpatient adolescent drug and alcohol rehabilitation program because he had become dependent on marijuana with its associated behavioral, interpersonal, scholastic, and antisocial problems. Keith and most of his friends had experimented several times with LSD, beer, and several other drugs but never used injection drugs. Marijuana was clearly Keith's drug of choice and the only drug he used with regularity. Approximately 1 year later, Keith graduated from the treatment program. He completed the early aftercare component, relapsed several times, and completed a 4-month refresher drug rehabilitation program in another state. Nine years after admission to the first rehabilitation program, Keith finally attained some adult goals. Now 34 years old, he has been drug-free for 10 years. He is the president and owner of a successful discount cellular phone business that he started. More important, a decade ago, he reestablished an excellent and close relationship with his parents. As far as I can tell, Keith remains drug-free except for an occasional beer.

Topics: Adolescent; Adult; Cannabis; Dronabinol; Drug and Narcotic Control; Humans; Internet; Male; Marijuana Abuse; Memory Disorders; Memory, Short-Term; Phytotherapy; United States

One of the most often reported cognitive deficits of acute cannabis administration is an impaired recall of previously learned information.. The aim of the present study was to determine whether cannabis-induced memory impairment in humans is mediated via glutamatergic or cholinergic pathways.. Fifteen occasional cannabis users participated in a double-blind, placebo-controlled, six-way cross-over study. On separate test days, subjects received combinations of pretreatment (placebo, vardenafil 20 mg or rivastigmine 3 mg) and treatment (placebo or 1,376 mg cannabis/kg body weight). Cognitive tests were administered immediately after inhalation of treatment was finished and included measures of memory (visual verbal learning task, prospective memory test, Sternberg memory test), perceptual-motor control (critical tracking task), attention (divided attention task) and motor impulsivity (stop signal task).. The results of this study demonstrate that subjects under the influence of cannabis were impaired in all memory tasks, in critical tracking, divided attention and the stop signal task. Pretreatment with rivastigmine attenuated the effect of cannabis on delayed recall and showed a trend towards significance on immediate recall. When cannabis was given in combination with vardenafil, there were no significant interaction effects in any of the tasks.. The present data therefore suggest that acetylcholine plays an important role in cannabis-induced memory impairment, whereas similar results for glutamate have not been demonstrated in this study.

Topics: Acetylcholine; Adult; Attention; Cannabinoids; Cannabis; Cognition; Cross-Over Studies; Double-Blind Method; Female; Glutamic Acid; Humans; Imidazoles; Male; Marijuana Smoking; Memory; Memory Disorders; Memory, Short-Term; Phenylcarbamates; Piperazines; Prospective Studies; Rivastigmine; Sulfones; Triazines; Vardenafil Dihydrochloride; Verbal Learning; Young Adult

Community-based studies suggest that cannabis products that are high in Δ⁹-tetrahydrocannabinol (THC) but low in cannabidiol (CBD) are particularly hazardous for mental health. Laboratory-based studies are ideal for clarifying this issue because THC and CBD can be administered in pure form, under controlled conditions. In a between-subjects design, we tested the hypothesis that pre-treatment with CBD inhibited THC-elicited psychosis and cognitive impairment. Healthy participants were randomised to receive oral CBD 600 mg (n=22) or placebo (n=26), 210 min ahead of intravenous (IV) THC (1.5 mg). Post-THC, there were lower PANSS positive scores in the CBD group, but this did not reach statistical significance. However, clinically significant positive psychotic symptoms (defined a priori as increases ≥ 3 points) were less likely in the CBD group compared with the placebo group, odds ratio (OR)=0.22 (χ²=4.74, p<0.05). In agreement, post-THC paranoia, as rated with the State Social Paranoia Scale (SSPS), was less in the CBD group compared with the placebo group (t=2.28, p<0.05). Episodic memory, indexed by scores on the Hopkins Verbal Learning Task-revised (HVLT-R), was poorer, relative to baseline, in the placebo pre-treated group (-10.6 ± 18.9%) compared with the CBD group (-0.4% ± 9.7 %) (t=2.39, p<0.05). These findings support the idea that high-THC/low-CBD cannabis products are associated with increased risks for mental health.

Topics: Adult; Cannabidiol; Cannabis; Cognitive Dysfunction; Double-Blind Method; Dronabinol; Drug Interactions; Female; Hippocampus; Humans; Learning; Male; Memory Disorders; Paranoid Disorders

It has long been known that acute marijuana administration impairs working memory (e.g., the discrimination of stimuli separated by a delay). The determination of which of the individual components of memory are altered by marijuana is an unresolved problem. Previous human studies did not use test protocols that allowed for the determination of delay-independent (initial discrimination) from delay-dependent (forgetting or retrieval) components of memory. Using methods developed in the experimental analysis of behavior and signal detection theory, we tested the acute effects of smoked marijuana on forgetting functions in 5 humans. Immediately after smoking placebo, a low dose, or a high dose of marijuana (varying in delta9-THC content), subjects completed delayed match-to-sample testing that included a range of retention intervals within each test session (0.5, 4, 12, and 24 s). Performances (discriminability) at each dose were plotted as forgetting functions, as described and developed by White and colleagues (White, 1985; White & Ruske, 2002). For all 5 subjects, both delta9-THC doses impaired delay-dependent discrimination but not delay-independent discrimination. The outcome is consistent with current nonhuman studies examining the role of the cannabinoid system on delayed matching procedures, and the data help illuminate one behavioral mechanism through which marijuana alters memory performance.

Topics: Adult; Cannabis; Female; Humans; Male; Memory Disorders; Neuropsychological Tests

To evaluate the sensitivity of a computerized cognitive-neuromotor test battery in assessing the effects of marijuana (delta-9-tetrahydrocannabinol [THC]), we conducted a study of 10 healthy male volunteers who were experienced marijuana smokers. After extensive training on the performance tasks, each subject was tested on three separate days after smoking a cigarette containing either 1.75% THC, 3.55% THC, or placebo according to a randomized double-blind repeated measures design. Testing was carried out before smoking and 30, 90, and 150 minutes after smoking the cigarette. Of the five tasks employed, the digit-symbol substitution test with memory and the reaction time task were the measures most sensitive to effects of marijuana. We examined the usefulness of the coefficient of variation and effect size as indices of sensitivity to be used across different types of tasks.

Topics: Adult; Blood Pressure; Cannabis; Cognition Disorders; Diagnosis, Computer-Assisted; Double-Blind Method; Dronabinol; Heart Rate; Humans; Male; Memory Disorders; Motor Skills; Reaction Time; Self-Assessment; Substance-Related Disorders; Task Performance and Analysis

Sixteen college-educated male subjects were tested on free-recall lists during intoxication with marijuana extract calibrated to 0.3 mg/kg delta-9-tetrahydrocannabinol and during placebo conditions. On each testing day subjects studied six lists using a regular overt rehearsal procedure and six lists using an association-overt rehearsal procedure in which they were to rehearse alound both list items and associations to those items. Both marijuana and the association-rehearsal procedure reduced the number of correct recalls and increased the number of intrusions (nonlist items which were incorrectly recalled as having been on the list to be learned). The intrusions were divided into three categories: a) words found on prior lists; b) associates spoken during the rehearsal; or c) totally new works not previously mentioned. Marijuana significantly increased the number of new intrusions; the association-rehearsal procedure did not. This result suggests that one of the effects of marijuana on cognitive functions in humans is to increase the number of intrusive thoughts and this may be the mechanism involved in some of the thought disorder observed with marijuana intoxication.

Topics: Acute Disease; Adolescent; Adult; Association Learning; Cannabinoids; Cannabis; Cognition; Humans; Male; Memory Disorders; Models, Neurological

Cannabis use has been linked to poorer episodic memory. However, little is known about whether depression and sex may interact as potential moderators of this association, particularly among adolescents. The current study addresses this by examining interactions between depression symptoms and sex on the association between cannabis use and episodic memory in a large sample of adolescents.. Cross-sectional data from 360 adolescents (. The effect of the three-way interaction among cannabis use, depression symptoms, and sex did not have a significant impact on episodic memory performance. However, follow-up analyses revealed a significant effect of the two-way interaction of cannabis use and depression symptoms on episodic memory, such that associations between cannabis use and episodic memory were only significant at lower and average levels of depression symptoms.. Contrary to our hypotheses, we found that as depression symptoms increased, the negative association between cannabis use and episodic memory diminished. Given the use of a predominantly subsyndromic sample, future studies should attempt to replicate findings among individuals with more severe depression.

Topics: Adolescent; Cannabis; Child; Cross-Sectional Studies; Depression; Humans; Longitudinal Studies; Memory Disorders; Memory, Episodic

There are general inhibitory effects of exo-cannabinoids on dopamine-mediated behaviors. Many studies suggested the interaction between cannabinoid receptors and dopamine receptors in the brain that affect cognition behaviors. In this paper, we investigate the effects of marijuana on 6-OHDA-induced cognitive impairments and the expression of dopamine and cannabinoid receptors in the hippocampus of male rats. 42 rats were divided into six groups. 6-hydroxy dopamine (6-OHDA) was administrated into the substantia nigra. Marijuana (60 mg/kg; i.p.) was administered 28 days, one week after the 6-OHDA injection. Morris water maze (MWM) and novel object recognition tests were performed. The hippocampal expression levels of cannabinoid receptors and D1 and D2 dopamine receptors evaluate by real-time PCR. The results showed marijuana improved the spatial learning and memory disorders caused by 6-OHDA in the MVM task and novel object recognition test. Additionally, the level of both D1 and D2 mRNA was decreased in 6-OHDA-treated animals and marijuana consumption only increased the hippocampal level of D1 mRNA. Moreover, the level of hippocampal CB1 mRNA in 6-OHDA- treated rats was higher than in control rats. However, the hippocampal level of CB2 mRNA was decreased in 6-OHDA- treated rats. Marijuana consumption caused a significant decrease in CB1 mRNA level and an increase in CB2 mRNA level in 6-OHDA + marijuana group. Therefore, marijuana may be helpful for learning & memory disorders, D1, and D2 dopamine receptors, and cannabinoid receptor alteration in patients with Parkinson's disease.

Topics: Animals; Cannabis; Cognition; Dopamine; Hippocampus; Male; Memory Disorders; Oxidopamine; Rats; Receptors, Cannabinoid; Receptors, Dopamine D1; Receptors, Dopamine D2; Spatial Learning

Most studies related to hemp are focused on Cannabidiol (CBD) and Tetrahydrocannabinol (THC); however, up to 120 types of phytocannabinoids are present in hemp. Hemp leaves contain large amounts of Cannabidiolic acid (CBDA) and Tetrahydrocannabinolic acid (THCA), which are acidic variants of CBD and THC and account for the largest proportion of CBDA. In recent studies, CBDA exhibited anti-hyperalgesia and anti-inflammatory effects. THCA also showed anti-inflammatory and neuroprotective effects that may be beneficial for treating neurodegenerative diseases. CBDA and THCA can penetrate the blood-brain barrier (BBB) and affect the central nervous system. The purpose of this study was to determine whether CBDA and THCA ameliorate Alzheimer's disease (AD)-like features in vitro and in vivo. The effect of CBDA and THCA was evaluated in the Aβ

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Cannabidiol; Cannabinoids; Cannabis; Dronabinol; Memory Disorders; Mice; Neuroprotective Agents

Bipolar disorder (BD) and cannabis use are each associated with neurocognitive deficits in adolescents. However, little is known regarding the association of neurocognition with cannabis use among adolescents with BD. Therefore, we examined this topic in a sample of adolescents with BD and healthy control (HC) adolescents.. Participants included 121 adolescents (. These preliminary findings suggest that cannabis use among adolescents with BD is associated with working memory deficits. Future studies in larger samples are warranted to evaluate causation versus predisposition to cannabis use, and to evaluate duration, quantity, and potency of cannabis on neurocognition among adolescents with BD.

Topics: Adolescent; Attention; Bipolar Disorder; Cannabis; Humans; Memory Disorders; Memory, Short-Term; Neuropsychological Tests

More older adults are using cannabis for recreational and/or medical purposes, but most studies examining cognitive function and cannabis use do not include older adults. The current small pilot study sought to compare cognitive function and emotional functioning among adults age 60 and older who were regular, primarily recreational cannabis users (

Topics: Aged; Cannabis; Cognition; Executive Function; Humans; Memory Disorders; Memory, Short-Term; Pilot Projects

Compromised cognitive control in cannabis use-tempting situations is thought to play a key role in the development of cannabis use disorders. However, little is known about how exposure to cannabis cues and contexts may influence cognitive control and the underlying neural mechanisms in cannabis users.. Working memory (WM) is an attention reliant executive function central to cognitive control. In this study, we investigated how distracting cannabis words affected WM load-dependent performance and related brain activity in near-daily cannabis users (N = 36) relative to controls (N = 33).. Brain activity was recorded during a novel N-back flanker WM task with neutral and cannabis flankers added as task-irrelevant distractors.. On a behavioural level, WM performance did not differ between groups, and the presence of cannabis flankers did not affect performance. However, in cannabis users compared to controls, the presence of cannabis flankers reduced WM load-related activity in multiple regions, including the insula, thalamus, superior parietal lobe and supramarginal gyrus.. The group specificity of these effects suggest that cannabis users might differ from controls in the way they process cannabis-related cues and that cannabis cue exposure could interfere with other cognitive processes under cognitively demanding circumstances. Future studies should focus on the role of context in cognitive control-related processes like WM and attention to further elucidate potential cognitive impairments in heavy cannabis users and how these relate to loss of control over drug seeking itself.

Topics: Brain; Cannabinoid Receptor Agonists; Cannabis; Cognition; Magnetic Resonance Imaging; Memory Disorders; Memory, Short-Term; Parietal Lobe

The association between cannabis exposure and working memory impairment and its neural substrates remain unclear. In this cross-sectional observational study, we investigated this by examining the relationship between frequency of exposure to cannabis, working memory performance and regional brain volumes and tested whether lower volumes of cortical and subcortical structures mediate the association between cannabis exposure and working memory deficit using the Human Connectome Project data from 234 individuals with self-reported cannabis exposure and 174 individuals unexposed to cannabis. We tested the relationship between self-reported frequency of cannabis exposure and list-sorting working memory task performance (total number of correct responses), between T1 weighted MRI-derived regional grey-matter volumes and working memory task performance as well as between frequency of cannabis exposure and brain volumes after controlling for potential confounders. Finally, mediation analysis was carried out to test whether deficit in working memory performance associated with cannabis use was mediated by its association with lower grey-matter volume. Participants who reported higher frequency of cannabis use tended to have lower number of correct responses in the list-sorting working memory task and lower bilateral hippocampal volumes. Association between severity of cannabis exposure as indexed by frequency of cannabis use and impairment in working memory was mediated by lower left hippocampal volume in cannabis users. We report evidence in support of the left hippocampus volume-mediated working memory impairment associated with recreational cannabis exposure. Future studies employing prospective longitudinal design are necessary to examine the cause-effect relationships of cannabis exposure on working memory and brain volumes.

Topics: Adolescent; Adult; Cannabis; Cross-Sectional Studies; Female; Gray Matter; Hippocampus; Humans; Magnetic Resonance Imaging; Male; Marijuana Use; Mediation Analysis; Memory Disorders; Memory, Short-Term; Young Adult

Cannabis contains over 700 known cannabinoids, terpenoids, flavonoids, and so on; however, the roles and importance of these components have yet to be fully understood. Δ

Topics: Animals; Brain Injuries; Cannabinoids; Cannabis; Catalepsy; Disease Models, Animal; Humans; Memory Disorders; Mice; Risk; Spatial Memory

Prospective memory pervades our daily lives and failures can have detrimental consequences. This ability to execute delayed intentions may be impacted by stress, yet few studies have examined these effects. Moreover, as many cannabis users report using cannabis to cope with stress, it is important to understand how stress impacts memory in cannabis users.. We assessed the effects of acute and chronic stress on prospective memory to examine whether stress differentially impacts prospective memory in cannabis users vs. non-users.. Forty cannabis users and 42 non-users were assigned an episodic and a habitual prospective memory test before completing either the stress or no stress condition of the Maastricht Acute Stress Test (MAST). Participants were instructed to execute the habitual test during the MAST and the episodic test shortly after the MAST. Chronic stress was measured using the Perceived Stress Scale, and acute stress was measured using subjective ratings and cortisol.. There was a main effect of acute stress indicating that stress detrimentally impacted habitual prospective memory performance. Although there was not a significant stress x cannabis interaction, further planned comparisons indicated the habitual prospective memory impairment was selective to cannabis users. There were also significant negative correlations between (i) episodic prospective memory and both subjective stress as well as chronic stress, and (ii) habitual prospective memory and change in subjective stress.. This study is the first to reveal detrimental effects of acute stress on prospective memory performance, which may be exacerbated in cannabis users.

Topics: Adaptation, Psychological; Adult; Cannabis; Female; Hallucinogens; Humans; Hydrocortisone; Male; Marijuana Smoking; Memory Disorders; Memory, Episodic; Stress, Psychological; Young Adult

Marijuana use is disproportionately prevalent among HIV-infected individuals. The strongest neurocognitive effect of marijuana use is impairment in the domain of memory. Memory impairment is also high among HIV-infected persons. The present study examined 69 HIV-infected individuals who were stratified by age of regular marijuana initiation to investigate how marijuana use impacts neurocognitive functioning. A comprehensive battery assessed substance use and neurocognitive functioning. Findings indicated early onset marijuana users (regular use prior to age 18), compared to non-marijuana users and late onset marijuana users (regular use at age 18 or later), were over 8 times more likely to have learning impairment and nearly 4 times more likely to have memory impairment. A similar pattern of early onset marijuana users performing worse in learning emerged when examining domain deficit scores. The potential for early onset of regular marijuana use to exacerbate already high levels of memory impairment among HIV-infected persons has important clinical implications, including increased potential for medication non-adherence and difficulty with independent living.

Topics: Adolescent; Adult; Cannabis; Cognition; Cognitive Dysfunction; Female; HIV Infections; Humans; Learning; Male; Marijuana Abuse; Marijuana Smoking; Marijuana Use; Memory Disorders; Memory, Short-Term; Middle Aged; Neuropsychological Tests; Substance-Related Disorders

Cannabis use is associated with a range of neurocognitive deficits, including impaired episodic memory. However, no study to date has assessed whether these difficulties extend to episodic foresight, a core component of which is the ability to mentally travel into one's personal future. This is a particularly surprising omission given that episodic memory is considered to be critical to engage episodic foresight.. In the present study, we provide the first test of how episodic foresight is affected in the context of differing levels of cannabis use, and the degree to which performance on a measure of this construct is related to episodic memory.. Fifty-seven regular cannabis users (23 recreational, 34 regular) and 57 controls were assessed using an adapted version of the Autobiographical Interview. The results showed that regular-users exhibited greater impairment of episodic foresight and episodic memory than both recreational-users and cannabis-naïve controls.. These data therefore show for the first time that cannabis-related disruption of cognitive functioning extends to the capacity for episodic foresight, and they are discussed in relation to their potential implications for functional outcomes in this group.

Topics: Adolescent; Adult; Cannabis; Cognition; Female; Hallucinogens; Humans; Male; Memory Disorders; Memory, Episodic; Neurocognitive Disorders; Substance-Related Disorders; Young Adult

Cannabis has been used for medicinal purpose for thousands of years; however the positive and negative effects of cannabis use in Parkinson's disease (PD) and Multiple Sclerosis (MS) are mostly unknown. Our aim was to assess cannabis use in PD and MS and compare results of self-reported assessments of neurological disability between current cannabis users and non-users.. An anonymous web-based survey was hosted on the Michael J. Fox Foundation and the National Multiple Sclerosis Society webpages from 15 February to 15 October 2016. The survey collected demographic and cannabis use information, and used standardized questionnaires to assess neurological function, fatigue, balance, and physical activity participation. Analysis of variance and chi-square tests were used for the analysis.. The survey was viewed 801 times, and 595 participants were in the final data set. Seventy-six percent and 24% of the respondents reported PD and MS respectively. Current users reported high efficacy of cannabis, 6.4 (SD 1.8) on a scale from 0 to 7 and 59% reported reducing prescription medication since beginning cannabis use. Current cannabis users were younger and less likely to be classified as obese (P < 0.035). Cannabis users reported lower levels of disability, specifically in domains of mood, memory, and fatigue (P<0.040).. Cannabis may have positive impacts on mood, memory, fatigue, and obesity status in people with PD and MS. Further studies using clinically and longitudinally assessed measurements of these domains are needed to establish if these associations are causal and determine the long-term benefits and consequences of cannabis use in people with PD and MS.

Topics: Adult; Affect; Aged; Cannabis; Disabled Persons; Fatigue; Female; Humans; Internet; Male; Marijuana Smoking; Medical Marijuana; Memory; Memory Disorders; Middle Aged; Mood Disorders; Multiple Sclerosis; Obesity; Parkinson Disease; Surveys and Questionnaires

While many studies suggest that regular cannabis use leads to deficits in cognitive functioning, particularly in memory, few have measured effort put forth during testing, and none have examined this as a potential mediator. Both age of onset of regular cannabis use and frequency of use have been linked to increased risk of memory deficits. The present study sought to determine whether effort mediated the relationship between frequency or age of onset of cannabis use and learning and memory performance.. Sixty-two participants (74% male, mean age = 19.25 years) who met criteria for chronic cannabis use (four or more days per week for at least 12 months) completed a neuropsychological battery including the California Verbal Learning Test-II (CVLT-II) and the Rey Complex Figure (RCF) as measures of learning and memory, and the Word Memory Test (WMT) as a measure of effort put forth during neuropsychological assessment.. Participants who more frequently used cannabis exhibited poorer effort (as measured by WMT performance; p < .01). Bootstrapping yielded 95% confidence intervals for indirect effects and revealed that effort significantly mediated the relationship between frequency of cannabis use and CVLT-II Learning (Sum of Trials 1-5), CVLT-II Delayed Recall, and RCF Delayed Recall, but not RCF Immediate Recall. Age of onset of cannabis use was not significantly related to effort.. Findings indicate that effort mediates the relationship between frequency of cannabis use and performance on learning and memory measures, suggesting that effort performance should be measured and controlled for in future studies assessing cognition in frequent cannabis users.

Topics: Adolescent; Cannabis; Cognition; Female; Humans; Male; Marijuana Smoking; Memory; Memory Disorders; Motivation; Neuropsychological Tests; Young Adult

Verbal memory difficulties are the most widely reported and persistent cognitive deficit associated with early onset marijuana use. Yet, it is not known what memory stages are most impaired in those with early marijuana use.. Forty-eight young adults, aged 18-25, who used marijuana at least once per week and 48 matched nonusing controls (CON) completed the California Verbal Learning Test, Second Edition (CVLT-II). Marijuana users were stratified by age of initial use: early onset users (EMJ), who started using marijuana at or before age 16 (n = 27), and late onset marijuana user group (LMJ), who started using marijuana after age 16 (n = 21). Outcome variables included trial immediate recall, total learning, clustering strategies (semantic clustering, serial clustering, ratio of semantic to serial clustering, and total number of strategies used), delayed recall, and percent retention.. Learning improved with repetition, with no group effect on the learning slope. EMJ learned fewer words overall than LMJ or CON. There was no difference between LMJ and CON in total number of words learned. Reduced overall learning mediated the effect on reduced delayed recall among EMJ, but not CON or LMJ. Learning improved with greater use of semantic versus serial encoding, but this did not vary between groups. EMJ was not related to delayed recall after adjusting for encoding.. Young adults reporting early onset marijuana use had learning weaknesses, which accounted for the association between early onset marijuana use and delayed recall. No amnestic effect of marijuana use was observed. (PsycINFO Database Record

Topics: Adolescent; Adult; Age Factors; Cannabis; Female; Humans; Male; Marijuana Smoking; Memory Disorders; Memory, Short-Term; Mental Recall; Verbal Learning; Young Adult

Research shows that cannabis users exhibit deficits in prospective memory (PM) and executive function, which persist beyond acute intoxication. However, many studies rely on self-reports of memory failures or use laboratory-based measures that may not mimic functional deficits in the real world. The present study aimed to assess real-world memory functioning.. Twenty cannabis-only users and 20 non-illicit drug users were recruited. Participants completed a substance use inventory and a mood scale, followed by a non-immersive virtual reality task assessing PM and executive functioning. The task involved the participant playing the role of an office worker for the day and performing routine office duties. A number of subscales were used to assess facets of executive function (planning, adaptive thinking, creative thinking, selection, prioritisation) and PM (time-based, event-based and action-based PM).. Multivariate analysis of variance revealed cannabis users performed worse overall on the task, with poor performance on the planning, time-based PM and event-based PM subscales. In addition, indices of cannabis (length, dose, frequency, total use) were correlated with performance on these three subscales.. The present study expands on previously established research, providing support for the cannabis-related deficits in PM and executive functioning, and the role of different aspects of cannabis use in these deficits.

Topics: Adolescent; Cannabis; Executive Function; Female; Humans; Male; Marijuana Smoking; Memory Disorders; Memory, Episodic; Multivariate Analysis; Time Factors; Young Adult

Prospective memory (PM) deficits in recreational drug users have been documented in recent years. However, the assessment of PM has largely been restricted to self-reported measures that fail to capture the distinction between event-based and time-based PM. The aim of the present study is to address this limitation.. Extending our previous research, we augmented the range laboratory measures of PM by employing the CAMPROMPT test battery to investigate the impact of illicit drug use on prospective remembering in a sample of cannabis only, ecstasy/polydrug and non-users of illicit drugs, separating event and time-based PM performance. We also administered measures of executive function and retrospective memory in order to establish whether ecstasy/polydrug deficits in PM were mediated by group differences in these processes.. Ecstasy/polydrug users performed significantly worse on both event and time-based prospective memory tasks in comparison to both cannabis only and non-user groups. Furthermore, it was found that across the whole sample, better retrospective memory and executive functioning was associated with superior PM performance. Nevertheless, this association did not mediate the drug-related effects that were observed. Consistent with our previous study, recreational use of cocaine was linked to PM deficits.. PM deficits have again been found among ecstasy/polydrug users, which appear to be unrelated to group differences in executive function and retrospective memory. However, the possibility that these are attributable to cocaine use cannot be excluded.

Topics: Amphetamine-Related Disorders; Cannabis; Case-Control Studies; Female; Humans; Male; Marijuana Abuse; Memory; Memory Disorders; Memory, Long-Term; N-Methyl-3,4-methylenedioxyamphetamine; Psychological Tests; Retention, Psychology; Substance-Related Disorders; Surveys and Questionnaires

Stimulants are used increasingly to enhance social (cocaine) or cognitive performance (stimulants normally prescribed, prescription stimulants [e.g., methylphenidate, amphetamines]). Chronic use, by contrast, has been associated with significant verbal memory and learning deficits. This study sought to determine whether subtle learning and memory problems characterize individuals who exhibit occasional but not chronic use of stimulants.. One hundred fifty-four young (age 18-25), occasional, nondependent stimulant users and 48 stimulant-naive comparison subjects performed the California Verbal Learning Test II. Lifetime uses of stimulants and co-use of marijuana were considered in correlation and median split analyses.. Compared with stimulant-naive subjects, occasional stimulant users showed significant performance deficits, most pronounced in the verbal recall and recognition domains. Lifetime uses of stimulants and marijuana did not affect California Verbal Learning Test II performance. The type of stimulant used, however, was of major relevance: users of cocaine only were less impaired, whereas cumulative use of prescription stimulants was associated with impaired verbal learning and memory capacities.. These results support the hypothesis of subtle and possibly pre-existing neurocognitive deficiencies in occasional users of stimulants, which might be related to the motivation for using these drugs. More importantly, despite beneficial short-term effects, cumulative use, particularly of prescription amphetamines and methylphenidate, intensifies these deficits.

Topics: Adolescent; Adult; Amphetamines; Cannabis; Central Nervous System Stimulants; Cocaine; Female; Humans; Male; Memory Disorders; Prescription Drugs; Verbal Learning

Ecstasy (street name for [+/-]-3,4-methylenedioxymethamphetamine [MDMA]) use has been associated with cognitive deficits, especially in verbal memory. However, owing to the cross-sectional and retrospective nature of currently available studies, questions remain regarding the causal direction and clinical relevance of these findings.. To examine the relationship between Ecstasy use and subsequent cognitive performance.. A prospective cohort study in Ecstasy-naive subjects with a high risk for future first Ecstasy use, as part of the Netherlands XTC Toxicity study. The initial examination took place between April 10, 2002, and April 28, 2004; follow-up was within 3 years after the initial examination.. One hundred eighty-eight healthy Ecstasy-naive volunteers (mean age, 22 years) were recruited. Of these, 58 subjects started using Ecstasy (mean cumulative dose, 3.2 tablets; median cumulative dose, 1.5 tablets). They were compared with 60 persistent Ecstasy-naive subjects matched on age, sex, intelligence, and use of substances other than Ecstasy. Differences in cognition between Ecstasy users and Ecstasy-naive subjects were adjusted for differences in cannabis and other recreational drug use.. Change scores between the initial examination and follow-up on neurocognitive tests measuring attention, working memory, verbal and visual memory, and visuospatial ability.. At the initial examination, there were no statistically significant differences in any of the neuropsychological test scores between persistent Ecstasy-naive subjects and future Ecstasy users. However, at follow-up, change scores on immediate and delayed verbal recall and verbal recognition were significantly lower in the group of incident Ecstasy users compared with persistent Ecstasy-naive subjects. There were no significant differences on other test scores.. Our findings suggest that even a first low cumulative dose of Ecstasy is associated with decline in verbal memory. Although the performance of the group of incident Ecstasy users is still within the normal range and the immediate clinical relevance of the observed deficits is limited, long-term negative consequences cannot be excluded.

Topics: Adult; Attention; Cannabis; Cognition; Cognition Disorders; Cohort Studies; Female; Follow-Up Studies; Humans; Illicit Drugs; Male; Memory; Memory Disorders; N-Methyl-3,4-methylenedioxyamphetamine; Netherlands; Neuropsychological Tests; Prospective Studies; Risk Factors; Substance-Related Disorders; Verbal Behavior

Recent research suggests that not only does the use of recreational drugs impact on working memory functioning, but more ;everyday' aspects of memory (e.g. remembering to do something in the future) are also affected. Forty-three ecstasy-polydrug users and 51 non-ecstasy users were recruited from a university population. Each participant completed the Cognitive Failures Questionnaire (CFQ) and Everyday Memory Questionnaire (EMQ). Of these, 28 ecstasy-polydrug users and 35 non-ecstasy users completed the Prospective Memory Questionnaire (PMQ). In addition, an objective measure of cognitive failures (the CFQ-for-others) was completed by friends of participants. With the exception of the CFQ-for-others, in each regression equation, cannabis emerged as the only significant predictor of everyday and prospective memory deficits. Significant correlations were found between the different indicators of everyday memory and various measures of illicit drug use. Cannabis featured prominently in this respect. The present study provides further support for cannabis related deficits in aspects of everyday memory functioning. Ecstasy may aLso be associated with cognitive slips, but not to the same extent as cannabis.

Topics: Adult; Cannabis; Cognition Disorders; Female; Hallucinogens; Humans; Illicit Drugs; Linear Models; Male; Memory; Memory Disorders; N-Methyl-3,4-methylenedioxyamphetamine; Substance-Related Disorders; Surveys and Questionnaires

3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is neurotoxic in animal studies and its use has been associated with cognitive impairments in humans.. To study hippocampal activation during the retrieval from episodic memory in polyvalent users of ecstasy.. Twelve polyvalent ecstasy users and twelve matched controls were examined by means of functional magnetic resonance imaging (fMRI) while they retrieved face-profession associations from episodic memory.. Ecstasy users had a normal structural MRI scan without focal brain lesions or anatomical abnormalities. They exhibited equal retrieval accuracy during memory retrieval to that of the matched controls. Yet, their retrieval-related activity was lower and more spatially restricted in the left anterior hippocampus than that of the controls.. These results provide evidence for abnormal hippocampal functioning in MDMA users even at the presence of normal memory performance. This finding may be linked to MDMA-induced neurotoxicity and suggests that diminished hippocampal activation during memory retrieval might be a more sensitive or earlier index of MDMA-related neurotoxicity than neuropsychological performance.

Topics: Adult; Amphetamine; Brain Mapping; Cannabis; Female; Hallucinogens; Hippocampus; Humans; Magnetic Resonance Imaging; Male; Memory Disorders; N-Methyl-3,4-methylenedioxyamphetamine; Neuropsychological Tests; Oxygen; Reaction Time; Substance-Related Disorders

Topics: Cannabis; Hallucinogens; Humans; Memory Disorders; N-Methyl-3,4-methylenedioxyamphetamine

To investigate the effects of extract from Fructus cannabis (EFC) that can activate calcineurin on learning and memory impairment induced by chemical drugs in mice.. Bovine brain calcineurin and calmodulin were isolated from frozen tissues. The activity of calcineurin was assayed using p-nitrophenyl phosphate (PNPP) as the substrate. Step-down type passive avoidance test and water maze were used together to determine the effects of EFC on learning and memory dysfunction.. EFC activated calcineurin activity at a concentration range of 0.01-100 g/L. The maximal value of EFC on calcineurin activity (35 %+/-5 %) appeared at a concentration of 10 g/L. The chemical drugs such as scopolamine, sodium nitrite, and 45 % ethanol, and sodium pentobarbital induced learning and memory dysfunction. EFC administration (0.2, 0.4, and 0.8 g/kg, igx7 d) prolonged the latency and decreased the number of errors in the step-down test. EFC, given for 7 d, enhanced the spatial resolution of amnesic mice in water maze test. EFC overcome amnesia of three stages of memory process at the dose of 0.2 g/kg.. EFC with an activation role of calcineurin can improve the impaired learning and memory induced by chemical drugs in mice.

Topics: Animals; Avoidance Learning; Calcineurin; Cannabis; Drugs, Chinese Herbal; Male; Maze Learning; Memory Disorders; Mice; Plants, Medicinal; Scopolamine; Seeds

Research indicates that the use of recreational drugs, including MDMA ('ecstasy') can result in impairments in cognitive functioning. Recent evidence, based on accounts of 'on drug' effects and cortical binding ratios suggests that women may be more susceptible to the effects of MDMA; however, no research has explored whether there are differences in the long-term behavioural sequelae of the drug between men and women. In addition, little is known about the profile of functioning of the 'typical' user. The present investigation accessed a large sample of recreational drug users, using the Internet, to obtain self-reports of memory functioning with a view to exploring any differences in self-reported ability amongst male and female users, and the level of difficulty reported by the 'typical' ecstasy user. A web site (www.drugresearch.org.uk) was developed and used for data collection. Prospective memory ability was assessed using the Prospective Memory Questionnaire. Self-report of day-to-day memory performance was investigated using the Everyday Memory Questionnaire. The UEL Drug Questionnaire assessed the use of other substances. The number of mistakes made while completing the questionnaires was also taken as an objective measure of performance errors. Findings, based on datasets submitted from 763 respondents, indicate no differences in self-reports of functioning between male and female participants. An overall dissociation between the effects of cannabis and ecstasy on self-reported memory functioning and on the likelihood of making an error during the completion of the questionnaire was found. Typical ecstasy users were found to report significantly more difficulties in long-term prospective memory and to make more completion errors than users of other substances and drug naive controls. Whilst taking into account the fact that participants were recruited via the World Wide Web and that a number of stringent exclusion criteria were applied to the data, a number of conclusions can be drawn. Recreational drug users perceive their memory ability to be impaired compared to non-users. The type of memory difficulties reported varies depending upon the drug of choice. These difficulties are exacerbated in ecstasy users. Individuals reporting average levels of use of ecstasy are more likely to report memory problems than non-ecstasy drug users or drug free individuals. The deleterious effects of ecstasy are therefore not restricted to heavy or chronic users

Topics: Amphetamine-Related Disorders; Cannabis; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Hallucinogens; Humans; Internet; Male; Memory; Memory Disorders; N-Methyl-3,4-methylenedioxyamphetamine; Sex Factors; Surveys and Questionnaires; Time Factors

Topics: Adolescent; Adult; Cannabis; Humans; Male; Memory Disorders; Neuropsychological Tests; Substance-Related Disorders; Wechsler Scales

Topics: Alcoholic Intoxication; Amphetamine; Barbiturates; Brain; Cannabis; Cocaine; Emotions; Female; Hallucinations; Heroin Dependence; Humans; Libido; Male; Memory Disorders; Perceptual Disorders; Phytotherapy; Psychophysiology; Religion; Sexual Behavior; Sexual Dysfunction, Physiological; Substance-Related Disorders

Topics: Adolescent; Adult; Age Factors; Alcoholism; Cannabis; Cocaine; Female; Hallucinations; Heroin Dependence; Humans; Lysergic Acid Diethylamide; Male; Memory Disorders; Opium; Sex Factors; Smoking; Substance-Related Disorders; Switzerland

Topics: Adolescent; Adult; Cannabis; Humans; Learning; Male; Memory Disorders; Memory, Short-Term; Phytotherapy; Time Factors

Topics: Adolescent; Cannabis; Child Development; Euphoria; Humans; Legislation, Drug; Memory Disorders; Perceptual Disorders; Substance-Related Disorders

Topics: Adolescent; Adult; Age Factors; Aggression; Anxiety; Cannabis; Depression; Female; Health Surveys; Humans; Male; Memory Disorders; Sampling Studies; Social Class; Surveys and Questionnaires; White People

Topics: Cannabis; Drug and Narcotic Control; Drug Prescriptions; Financing, Government; Health Education; Humans; Legislation, Drug; Memory Disorders; Motivation; Motor Skills; Perception; Psychoses, Substance-Induced; Research Support as Topic; Social Values; Substance-Related Disorders; United States

Topics: Adolescent; Adult; Anxiety; Cannabis; Cognition Disorders; Community Health Services; Drug Tolerance; Female; Humans; India; Male; Memory Disorders; Paranoid Disorders; Personality; Phytotherapy; Psychoses, Substance-Induced; Set, Psychology; Socioeconomic Factors; Substance-Related Disorders; United States