Thomas M. Heffernan

Patterns of drug use and the influence of gender on self-reports of memory ability in ecstasy users: a web-based study

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 naïve 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. No gender differences were detected, suggesting that there may be a dissociation between cognitive impairment and cortical binding worthy of further exploration.

Nonequivalence of on-line and paper-and-pencil psychological tests: The case of the prospective memory questionnaire

There is growing evidence that Internet-mediated psychological tests can have satisfactory psychometric properties and can measure the same constructs as traditional versions. However, equivalence cannot be taken for granted. The prospective memory questionnaire (PMQ; Hannon, Adams, Harrington, Fries-Dias, & Gibson, 1995) was used in an on-line study exploring links between drug use and memory (Rodgers et al., 2003). The PMQ has four factor-analytically derived subscales. In a large (N763) sample tested via the Internet, only two factors could be recovered; the other two subscales were essentially meaningless. This demonstration of nonequivalence underlines the importance of on-line test validation. Without examination of its psychometric properties, one cannot be sure that a test administered via the Internet actually measures the intended construct.

A review of the literature on the cognitive effects of alcohol hangover.

AIMS Alcohol misuse is a prime social and health problem in the UK. This paper presents a critical review of literature on the performance effects in the morning after binge drinking - during the alcohol hangover. Several pathophysiological changes that both follow and outlast acute intoxication may give rise to alcohol hangover effects. We have identified 27 English language peer-reviewed studies that investigate aspects of psychological performance during alcohol hangover following controlled alcohol ingestion. However, the majority of studies had basic methodological shortcomings. Of eight laboratory studies rigorous enough to warrant serious attention, only two showed effects. We interpret these largely negative findings as evidence of an insensitivity that is intrinsic to laboratory-based studies of performance under the influence of alcohol. Several studies have investigated the cognitive consequences of hangover subsequent to naturalistic consumption, where participants have chosen what and where to drink. Although these studies have tended to show effects, participants were always informed at the outset that hangover effects were to be assessed, and participants knew which was the hangover condition. Under these circumstances expectancy effects have possibly contaminated the results significantly. Therefore, naturalistic alcohol consumption studies (and laboratory studies that did not employ a placebo) can be considered as being suggestive of hangover effects, but should not be interpreted as providing definitive evidence of such effects. In conclusion, although there is empirical evidence showing impaired performance as a result of the alcohol hangover, future studies should confirm these findings and overcome the shortcomings of previous research.

The Alcohol Hangover Research Group Consensus Statement on Best Practice in Alcohol Hangover Research

Alcohol-induced hangover, defined by a series of symptoms, is the most commonly reported consequence of excessive alcohol consumption. Alcohol hangovers contribute to workplace absenteeism, impaired job performance, reduced productivity, poor academic achievement, and may compromise potentially dangerous daily activities such as driving a car or operating heavy machinery. These socioeconomic consequences and health risks of alcohol hangover are much higher when compared to various common diseases and other health risk factors. Nevertheless, unlike alcohol intoxication the hangover has received very little scientific attention and studies have often yielded inconclusive results. Systematic research is important to increase our knowledge on alcohol hangover and its consequences. This consensus paper of the Alcohol Hangover Research Group discusses methodological issues that should be taken into account when performing future alcohol hangover research. Future research should aim to (1) further determine the pathology of alcohol hangover, (2) examine the role of genetics, (3) determine the economic costs of alcohol hangover, (4) examine sex and age differences, (5) develop common research tools and methodologies to study hangover effects, (6) focus on factor that aggravate hangover severity (e.g., congeners), and (7) develop effective hangover remedies.

Differential experiences of the psychobiological sequelae of ecstasy use: quantitative and qualitative data from an internet study

Previous work provided preliminary evidence that different patterns of use among ecstasy users may impact on perceived side-effects. Participants recruited via an ecstasy-related bulletin board differed in their responses compared to those recruited via other means. The present investigation compares self-reports of psychobiological dif.culties among ecstasy users recruited either via a bulletin board or by alternative methods. Qualitative data included reports of any negative or positive changes attributable to ecstasy use and reasons for cessation of use. An Internet-based design was utilized and 209 volunteers completed the study, 117 of whom were recruited via a bulletin board devoted to discussion of ecstasy. Psychobiological dif.culties attributable to ecstasy use varied, with mood .uctuation the most common. Differences between the two groups in the extent to which these problems were reported was found. Bulletin board recruits were less likely to report anxiety or poor concentration, but more likely to report tremors/twitches. For the whole sample, lifetime use was associated more with psychobiologial problems, although this pattern was stronger and more pervasive for the nonbulletin board participants. Bulletin board recruits were more aware of possible negative psychological effects and were more likely to report adopting harm reduction strategies. From the qualitative data three negative consequences of use were identi.ed, the most common of which was ëpsychological problemsí. In support of the quantitative .ndings the likelihood of reporting psychological problems increased with lifetime exposure to ecstasy in both recruitment conditions but interestingly this did not appear to impact on reasons for cessation of use. Participants also reported a number of effects that they regarded as bene.cial. Future research should also take these aspects of use into account.

What develops in visuo-spatial working memory development?

The present studies examined the nature of visuo-spatial working memory development using conventional visual span and spatial span measures. Children aged between 6 and 13 years and adults aged 18-38 years were employed as participants. In Study 1, visual span, spatial span, articulation rate, and verbal fluency competencies were measured. In Study 2, visual span and spatial span maintenance was subject to five interference formats: nil, speech articulation, verbal fluency, visual masking, and spatial tapping. Distinct developmental rates were found for the two span tasks, which in the older children were correlated with the verbal fluency measure. Study 2 provided experimental evidence of the contribution of executive and spatial processes to spatial and to visual span maintenance. The results are interpreted as indicating that these memory span procedures make complex demands upon the visuo-spatial working memory architecture and consequently a precise identification of the process that actually develop is compromised. It is suggested that a componential approach where tasks are constructed to tap specific working memory components would afford a more accurate understanding of the development of these processes.

Hair MDMA samples are consistent with reported ecstasy use: findings from a study investigating effects of ecstasy on mood and memory.

Aims: Our group has conducted several Internet investigations into the biobehavioural effects of self-reported recreational use of MDMA (3,4-methylenedioxymethamphetamine or Ecstasy) and other psychosocial drugs. Here we report a new study examining the relationship between self-reported Ecstasy use and traces of MDMA found in hair samples. Methods: In a laboratory setting, 49 undergraduate volunteers performed an Internet-based assessment which included mood scales and the University of East London Drug Use Questionnaire, which asks for history and current drug use. They also provided a hair sample for determination of exposure to MDMA over the previous month. Results: Self-report of Ecstasy use and presence in hair samples were consistent (p < 0.00001). Both subjective and objective measures predicted lower self-reported ratings of happiness and higher self-reported stress. Self-reported Ecstasy use, but not presence in hair, was also associated with decreased tension. Conclusion: Different psychoactive drugs can influence long-term mood and cognition in complex and dynamically interactive ways. Here we have shown a good correspondence between self-report and objective assessment of exposure to MDMA. These data suggest that the Internet has potentially high utility as a useful medium to complement traditional laboratory studies into the sequelae of recreational drug use.

The impact of excessive alcohol use on prospective memory: A brief review

Research into the cognitive consequences of chronic excessive alcohol use continues to grow. Despite this, little research has investigated what impact excessive alcohol use might have upon everyday remembering. An important aspect of everyday remembering is prospective memory (PM), which refers to the cognitive ability of remembering to carry out an intended action at some future point in time. The majority of the studies which have focused on what impact excessive alcohol use has upon PM in teenagers and young adults have consistently found that the excessive drinkers reported more lapses in their short term (e.g., forgetting to lock ones door upon leaving home) and long term (e.g., forgetting to post a letter on time) aspects of everyday PM, when compared to low-dose alcohol users or non-users. It is concluded from this review that PM deficits should be added to the growing list of neuropsychological sequelae associated with excessive alcohol use. The magnitude of the effects of alcohol on PM depends upon the amount of alcohol consumed and how long one has been drinking. Major limitations of these studies include their reliance upon the use of self-report measures of PM, the issue of polydrug use complicating the picture, the need to control for the co-morbidity of other conditions--such as depression, and better drug-screening methods. Therefore, further studies need to employ objective measures alongside self-report measures of PM, incorporate better controls for the use of other drugs and mood states, as well as extending the focus of the research to study what effect different patterns of alcohol use might have upon PM, e.g., what impact binge drinking has upon everyday PM. These findings have educational and applied relevance within the alcohol field.

Does cannabis use affect prospective memory in young adults

The aim of the present study was to examine prospective memory impairments associated with cannabis use in young adults. An independent measures design utilising pre-existing groups of users and non-users was employed in which an opportunity sample of 90 undergraduates studying at universities in the north east of England participated. The number of prospective memory failures reported on the Prospective Memory Questionnaire and the number of location—action combinations correctly recalled during a video-based prospective memory task were measured. The number of strategies used to assist memory, level of anxiety and depression, and use of alcohol, nicotine and any other recreational drugs in addition to cannabis were also measured and controlled during the analysis. Analysis revealed no significant differences in the number of self-reported prospective memory failures; however, cannabis users recalled significantly fewer location—action combinations than non-users in the video-based prospective memory task. The findings from the present study suggest that cannabis use has a detrimental effect on prospective memory ability in young adults but users may not be aware of these deficits.

Short-term prospective memory deficits in chronic back pain patients.

Objective: Chronic pain, particularly low back pain, is widespread. Although a great deal is known about the impact that this has on quality of life and physical activity, relatively little has been established regarding the more cognitive effects of pain. This study aims to find out whether individuals with chronic pain experience memory deficits in prospective memory (PM), the process of remembering to do things at some future point in time. Examples of PM include remembering to keep an appointment, such as a visit to a clinic, or to perform a particular task, such as paying a bill on time. Methods: The PM of 50 participants with chronic pain was compared with 50 pain-free participants. Each participant completed the Prospective Memory Questionnaire, which assesses three aspects of prospective memory (short-term habitual, long-term episodic, and internally cued), and records the use of strategies to aid remembering. Results: In comparison to those not in pain, participants with chronic pain had significantly impaired short-term prospective memory, an effect which was evident even after co-varying use of analgesics and other drugs. Conclusions: These findings provide new insights into prospective memory dysfunction in people with chronic pain. Possible mechanisms for this dysfunction are discussed and suggestions for future research given. PM = prospective memory; PMQ = Prospective Memory Questionnaire; MANCOVA = multivariate analyses of covariance.