Exploring Pathways to Gambling: Proposing the Integrated Risk and Protective Factors Model of Gambling Types.

Three linked studies, testing key aspects of the Pathways towards Problem and Pathological Gambling Model (Blaszczynski and Nower in Addiction 87(5):487-499, 2002), are presented. Study one comprised 204 students and 490 gambling forum users. It predicted differences in gambling severity, mental health and substance use across different motives for gambling. Those with a primary social motive for gambling displayed less severe gambling and anxiety than those without, with the primary coping subgroup displaying the most anxiety and depression. Those who gambled primarily to enhance positive affect reported severe gambling. Study two comprised 404 gambling forum users and 265 students. Similar groups to the Pathways Model emerged, with a behaviourally conditioned and an emotionally vulnerable group. Unexpectedly, however, those in the emotionally vulnerable group reported more severe cognitive distortions than the behaviourally conditioned group. The final study, 378 gambling forum users and 201 students, found, as predicted, that three distinct gambling groups emerged; (1) those with lower levels of psychopathology and higher levels of protective factors; (2) those with heightened pre-existing anxiety and depression, and moderate levels of protective factors; and (3) those with heightened impulsivity, psychopathology, offending behaviour and the least protective factors. Three gambling groups are consequently presented (Social Gambler; Affect-Regulation Gambler; Antisocial Gambler) alongside the proposed Integrated Risk and Protective Factors Model of Gambling Types (IRPF-MGT). Directions for future research and implications for practice are outlined.

An account of subjective probability judgment for joint events: Conjunctive and disjunctive.

Probability judgment is a vital part of many aspects of everyday life. In the present paper, we present a new theory of the way in which individuals produce probability estimates for joint events: conjunctive and disjunctive. We propose that a majority of individuals produce conjunctive (disjunctive) estimates by making a quasi-random adjustment, positive or negative, from the less (more) likely component probability with the other component playing no obvious role. In two studies, we produce evidence supporting propositions that follow from our theory. First, the component probabilities do appear to play the distinct roles we propose in determining the joint event probabilities. Second, contrary to probability theory and other accounts of probability judgment, we show that the conjunctive-less likely probability difference is unrelated to the more likely disjunctive probability difference (in normative theory these quantities are identical). In conclusion, while violating the norms of probability judgment, we argue that estimates produced in the manner we propose will be close enough to the normative values especially given the changing nature of the external environment and the incomplete nature of available information.

Executive processes and timing: Comparing timing with and without reference memory.

Temporal perception is influenced by executive function. However, performance on different temporal tasks is often associated with different executive functions. This study examined whether using reference memory during a task influenced how performance was associated with executive resources. Participants completed temporal generalisation and bisection tasks, in their normal versions involving reference memory and in episodic versions without reference memory. Each timing task had two difficulty levels: easy and hard. Correlations between performance on these tasks and measures of executive function (updating, inhibition, task switching, and access to semantic memory) were assessed. Accuracy on the temporal generalisation task was correlated with memory access for all versions of the task. Updating correlated with accuracy only for the reference memory-based version of the task. Temporal bisection performance presented a different pattern of correlations. The bisection point was negatively correlated with inhibition scores, except for the easy episodic condition. The Weber ratio, considered a measure of temporal sensitivity, was negatively correlated with memory access only in the hard episodic condition. Together, the findings suggest that previous models of generalisation and bisection may not accurately reflect the underlying cognitive processes involved in the tasks.

Paranormal belief, thinking style preference and susceptibility to confirmatory conjunction errors.

This study examines the extent to which belief in extrasensory perception (ESP), psychokinesis (PK) or life after death (LAD), plus need for cognition (NFC) and faith in intuition (FI), predict the generation of confirmatory conjunction errors. An opportunity sample (n = 261) completed sixteen conjunction problems manipulated across a 2 event type (paranormal vs. non-paranormal) × 2 outcome type (confirmatory vs. disconfirmatory) within subjects design. Three Generalised Linear Mixed Models - one per paranormal belief type - were performed. With respondent gender and age controlled for, ESP, PK and LAD beliefs were all associated with the making (vs. non-making) of conjunction errors both generally and specifically for confirmatory conjunctive outcomes. Event type had no impact. Individuals high in NFC were less likely to commit the fallacy. The role thinking style plays in shaping paranormal believers' susceptibility to confirmatory conjunction biases is discussed. Methodological issues and future research ideas are also considered.

Paranormal belief and errors of probabilistic reasoning: The role of constituent conditional relatedness in believers' susceptibility to the conjunction fallacy.

The present study examines the extent to which stronger belief in either extrasensory perception, psychokinesis or life-after-death is associated with a proneness to making conjunction errors (CEs). One hundred and sixty members of the UK public read eight hypothetical scenarios and for each estimated the likelihood that two constituent events alone plus their conjunction would occur. The impact of paranormal belief plus constituents' conditional relatedness type, estimates of the subjectively less likely and more likely constituents plus relevant interaction terms tested via three Generalized Linear Mixed Models. General qualification levels were controlled for. As expected, stronger PK beliefs and depiction of a positively conditionally related (verses conditionally unrelated) constituent pairs predicted higher CE generation. ESP and LAD beliefs had no impact with, surprisingly, higher estimates of the less likely constituent predicting fewer - not more - CEs. Theoretical implications, methodological issues and ideas for future research are discussed.

Updating of working memory in ecstasy polydrug users: Findings from fNIRS.

AIMS/OBJECTIVES: Cognitive deficits are now well documented in ecstasy (MDMA) users with type and relative demand of task emerging as important factors. The updating component of executive processes appears to be particularly affected. The study reported here used functional near infrared spectroscopy imaging to investigate changes in cortical haemodynamics during memory updating. METHOD: Twenty ecstasy users and 20 non-users completed verbal and spatial memory updating tasks and brain blood oxygenation and deoxygenation change was measured using functional near infrared spectroscopy. RESULTS: There was no interaction between group and difficulty on the updating tasks, though there was a significant main effect of difficulty on both tasks. The effects of group approached significance on the verbal updating task. There were significant differences in blood oxygenation and deoxygenation change at optodes centred over the right and left dorsolateral prefrontal cortex, with ecstasy users showing greater blood oxygenation than the other groups. DISCUSSION: The lack of a behavioural difference on both tasks but presence of blood oxygenation and deoxygenation changes in letter updating provides support for the notion that ecstasy-polydrug users are investing more effort to achieve the same behavioural output. Total lifetime dose was high, and recency of use was significantly related to most changes, suggesting that heavy and recent use may be particularly detrimental.

Measures of Bayesian Reasoning Performance on 'Normal' and 'Natural' Frequency Tasks.

While the majority of similar studies examining Bayesian reasoning investigate how participants avoid common errors such as base-rate neglect, the current research also examines whether different formats (frequency and probability) lead to a difference in levels of absolute accuracy. In Study One, older (≥60 years) and younger (18 to 29 years) participants completed tasks in probability and normalized frequency formats. In Study 2, participants completed tasks in probability and natural frequency formats. Findings are that frequencies lead to less over-estimation, particularly in natural frequency tasks, which also reveal an interaction between age and task format whereby older adults seem unaffected by format. There was no association found between format and the avoidance of errors such as base-rate neglect. Findings are discussed in the light of dual and multi-process theories of reasoning, having failed to support the theory that frequency formats elicit System 2 reasoning processes.

Reasoning deficits among illicit drug users are associated with aspects of cannabis use.

Deficits in deductive reasoning have been observed among ecstasy/polydrug users. The present study seeks to investigate dose-related effects of specific drugs and whether these vary with the cognitive demands of the task. One hundred and five participants (mean age 21.33, SD 3.14; 77 females, 28 males) attempted to generate solutions for eight one-model syllogisms and one syllogism for which there was no valid conclusion. All of the one-model syllogisms generated at least one valid conclusion and six generated two valid conclusions. In these six cases, one of the conclusions was classified as common and the other as non-common. The number of valid common inferences was negatively associated with the aspects of short-term cannabis use and with measures of IQ. The outcomes observed were more than simple post-intoxication effects since cannabis use in the 10 days immediately before testing was unrelated to reasoning performance. Following adjustment for multiple comparisons, the number of non-common valid inferences was not significantly associated with any of the drug-use measures. Recent cannabis use appears to impair the processes associated with generating valid common inferences while not affecting the production of non-common inferences. It is possible, therefore, that the two types of inference may recruit different executive resources, which may differ in their susceptibility to cannabis-related effects.

Temporal and visual source memory deficits among ecstasy/polydrug users.

OBJECTIVES: We wished to investigate whether source memory judgements are adversely affected by recreational illicit drug use. METHOD: Sixty-two ecstasy/polydrug users and 75 non ecstasy users completed a source memory task, in which they tried to determine whether or not a word had been previously presented and if so, attempted to recall the format, location and temporal position in which the word had occurred. RESULTS: While not differing in terms of the number of hits and false positive responses, ecstasy/polydrug users adopted a more liberal decision criterion when judging if a word had been presented previously. With regard to source memory, users were less able to determine the format in which words had been presented (upper versus lower case). Female users did worse than female nonusers in determining which list (first or second) a word was from. Unexpectedly, the current frequency of cocaine use was negative associated with list and case source memory performance. CONCLUSIONS: Given the role that source memory plays in everyday cognition, those who use cocaine more frequently might have more difficulty in everyday tasks such as recalling the sources of crucial information or making use of contextual information as an aid to learning.

Prospective memory deficits in illicit polydrug users are associated with the average long-term typical dose of ecstasy typically consumed in a single session.

RATIONALE: Neuroimaging evidence suggests that ecstasy-related reductions in SERT densities relate more closely to the number of tablets typically consumed per session rather than estimated total lifetime use. To better understand the basis of drug related deficits in prospective memory (p.m.) we explored the association between p.m. and average long-term typical dose and long-term frequency of use. METHOD: Study 1: Sixty-five ecstasy/polydrug users and 85 nonecstasy users completed an event-based, a short-term and a long-term time-based p.m. task. Study 2: Study 1 data were merged with outcomes on the same p.m. measures from a previous study creating a combined sample of 103 ecstasy/polydrug users, 38 cannabis-only users, and 65 nonusers of illicit drugs. RESULTS: Study 1: Ecstasy/polydrug users had significant impairments on all p.m. outcomes compared with nonecstasy users. Study 2: Ecstasy/polydrug users were impaired in event-based p.m. compared with both other groups and in long-term time-based p.m. compared with nonillicit drug users. Both drug using groups did worse on the short-term time-based p.m. task compared with nonusers. Higher long-term average typical dose of ecstasy was associated with poorer performance on the event and short-term time-based p.m. tasks and accounted for unique variance in the two p.m. measures over and above the variance associated with cannabis and cocaine use. CONCLUSIONS: The typical ecstasy dose consumed in a single session is an important predictor of p.m. impairments with higher doses reflecting increasing tolerance giving rise to greater p.m. impairment.

Electrophysiological evidence of atypical processing underlying mental set shifting in ecstasy polydrug and polydrug users.

Executive functioning deficits are reported in ecstasy users. However research into mental set switching has been equivocal, with behavioral studies suggesting the function is preserved. The current study sought to address the issue of switching deficits in ecstasy users by combining behavioral performance with electrophysiological correlates (electroencephalography; EEG). Twenty ecstasy polydrug users, 20 nonecstasy polydrug users, and 20 drug naive controls were recruited. Participants completed questionnaires about their drug use, sleep quality, fluid intelligence, and current mood state. Each participant completed a mental set switching task (the number-letter task) while EEG measures were recorded. Analysis of variance (ANOVA) revealed no between-group differences on performance of the task; however a regression suggested that ecstasy use was a significant predictor for performance, after controlling for cannabis use. Mixed ANOVA revealed a significant effect of group on the P3, with significant differences between both drug groups and naives. There was also an interaction between electrode and group on the P2 component, with ecstasy users differing from both other groups. On the P3 component the results suggest a reduction in positivity at parieto-occipital electrodes for drug users compared to controls. Furthermore a significant increase in negativity in ecstasy users compared to control groups could be observed in several occipito-parietal electrodes at an N2 component as well as observable atypicalities in early processing (P2) displayed by ecstasy users and polydrug controls. The present study provides evidence of atypical processing of attentional shifting in ecstasy and polydrug users. Deficits in this executive function could reflect cognitive inflexibility and paucity of rapid behavioral adjustment, which may be problematic in real world situations.

Self-reports of executive dysfunction in current ecstasy/polydrug Users.

OBJECTIVES/BACKGROUND: Ecstasy/polydrug users have exhibited deficits in executive functioning in laboratory tests. We sought to extend these findings by investigating the extent to which ecstasy/polydrug users manifest executive deficits in everyday life. METHODS: Forty-two current ecstasy/polydrug users, 18 previous (abstinent for at least 6 months) ecstasy/polydrug users, and 50 non-users of ecstasy (including both non-users of any illicit drug and some cannabis-only users) completed the self-report Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A) measure. RESULTS: Current ecstasy/polydrug users performed significantly worse than previous users and non-users on subscales measuring inhibition, self-monitoring, initiating action, working memory, planning, monitoring ongoing task performance, and organizational ability. Previous ecstasy/polydrug users did not differ significantly from non-users. In regression analyses, although the current frequency of ecstasy use accounted for statistically significant unique variance on 3 of the 9 BRIEF-A subscales, daily cigarette consumption was the main predictor in 6 of the subscales. CONCLUSIONS: Current ecstasy/polydrug users report more executive dysfunction than do previous users and non-users. This finding appears to relate to some aspect of ongoing ecstasy use and seems largely unrelated to the use of other illicit drugs. An unexpected finding was the association of current nicotine consumption with executive dysfunction.

The effects of 'ecstasy' (MDMA) on visuospatial memory performance: findings from a systematic review with meta-analyses.

To review, with meta-analyses where appropriate, performance differences between ecstasy (3,4-methylenedioxymethamphetamine) users and non-users on a wider range of visuospatial tasks than previously reviewed. Such tasks have been shown to draw upon working memory executive resources. Abstract databases were searched using the United Kingdom National Health Service Evidence Health Information Resource. Inclusion criteria were publication in English language peer-reviewed journals and the reporting of new findings regarding human ecstasy-users' performance on visuospatial tasks. Data extracted included specific task requirements to provide a basis for meta-analyses for categories of tasks with similar requirements. Fifty-two studies were identified for review, although not all were suitable for meta-analysis. Significant weighted mean effect sizes indicating poorer performance by ecstasy users compared with matched controls were found for tasks requiring recall of spatial stimulus elements, recognition of figures and production/reproduction of figures. There was no evidence of a linear relationship between estimated ecstasy consumption and effect sizes. Given the networked nature of processing for spatial and non-spatial visual information, future scanning and imaging studies should focus on brain activation differences between ecstasy users and non-users in the context of specific tasks to facilitate identification of loci of potentially compromised activity in users.

The effects of heavy social drinking on executive function: a systematic review and meta-analytic study of existing literature and new empirical findings.

BACKGROUND: Previous investigations of executive function in alcohol dependent and in social drinkers have not always produced consistent results and have not utilised key indicators of recent theoretical models of Executive Function (EF). The present paper reports the results of two studies that seek to address these limitations. METHOD: Study 1 took the form of a systematic review and meta-analysis of studies examining EF in social drinkers. In Study 2, 41 participants completed an alcohol use inventory and were assigned to either light or heavy alcohol use via median split of average weekly dose. Participants completed measures of the fractionated executive processes of updating, shifting, inhibition and access to semantic memory. RESULTS: Study 1 only identified seven studies of EF in social drinkers, and the mean effect size was non-significant. In study 2, the heavy alcohol use group performed worse on all measures of executive functioning except memory updating. CONCLUSIONS: To our knowledge, this is the first systematic investigation of executive functioning in social drinkers. Given that the participants were non-treatment seeking social drinking students, the EF deficit in the heavy user group is particularly worrying and could increase the likelihood of developing an alcohol use disorder.

Effects of ecstasy/polydrug use on memory for associative information.

RATIONALE: Associative learning underpins behaviours that are fundamental to the everyday functioning of the individual. Evidence pointing to learning deficits in recreational drug users merits further examination. OBJECTIVES: A word pair learning task was administered to examine associative learning processes in ecstasy/polydrug users. METHODS: After assignment to either single or divided attention conditions, 44 ecstasy/polydrug users and 48 non-users were presented with 80 word pairs at encoding. Following this, four types of stimuli were presented at the recognition phase: the words as originally paired (old pairs), previously presented words in different pairings (conjunction pairs), old words paired with new words, and pairs of new words (not presented previously). The task was to identify which of the stimuli were intact old pairs. RESULTS: Ecstasy/ploydrug users produced significantly more false-positive responses overall compared to non-users. Increased long-term frequency of ecstasy use was positively associated with the propensity to produce false-positive responses. It was also associated with a more liberal signal detection theory decision criterion value. Measures of long term and recent cannabis use were also associated with these same word pair learning outcome measures. Conjunction word pairs, irrespective of drug use, generated the highest level of false-positive responses and significantly more false-positive responses were made in the divided attention condition compared to the single attention condition. CONCLUSIONS: Overall, the results suggest that long-term ecstasy exposure may induce a deficit in associative learning and this may be in part a consequence of users adopting a more liberal decision criterion value.

The relationships of 'ecstasy' (MDMA) and cannabis use to impaired executive inhibition and access to semantic long-term memory.

This study aimed to examine the relationship between the consumption of ecstasy (3,4-methylenedioxymethamphetamine (MDMA)) and cannabis, and performance on the random letter generation task which generates dependent variables drawing upon executive inhibition and access to semantic long-term memory (LTM). The participant group was a between-participant independent variable with users of both ecstasy and cannabis (E/C group, n = 15), users of cannabis but not ecstasy (CA group, n = 13) and controls with no exposure to these drugs (CO group, n = 12). Dependent variables measured violations of randomness: number of repeat sequences, number of alphabetical sequences (both drawing upon inhibition) and redundancy (drawing upon access to semantic LTM). E/C participants showed significantly higher redundancy than CO participants but did not differ from CA participants. There were no significant effects for the other dependent variables. A regression model comprising intelligence measures and estimates of ecstasy and cannabis consumption predicted redundancy scores, but only cannabis consumption contributed significantly to this prediction. Impaired access to semantic LTM may be related to cannabis consumption, although the involvement of ecstasy and other stimulant drugs cannot be excluded here. Executive inhibitory functioning, as measured by the random letter generation task, is unrelated to ecstasy and cannabis consumption.

Prospective memory functioning among ecstasy/polydrug users: evidence from the Cambridge Prospective Memory Test (CAMPROMPT).

RATIONALE: 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. OBJECTIVES: 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. RESULTS: 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. CONCLUSIONS: 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.

Everyday and prospective memory deficits in ecstasy/polydrug users.

The impact of ecstasy/polydrug use on real-world memory (i.e. everyday memory, cognitive failures and prospective memory [PM]) was investigated in a sample of 42 ecstasy/polydrug users and 31 non-ecstasy users. Laboratory-based PM tasks were administered along with self-reported measures of PM to test whether any ecstasy/polydrug-related impairment on the different aspects of PM was present. Self-reported measures of everyday memory and cognitive failures were also administered. Ecstasy/polydrug associated deficits were observed on both laboratory and self-reported measures of PM and everyday memory. The present study extends previous research by demonstrating that deficits in PM are real and cannot be simply attributed to self-misperceptions. The deficits observed reflect some general capacity underpinning both time- and event-based PM contexts and are not task specific. Among this group of ecstasy/polydrug users recreational use of cocaine was also prominently associated with PM deficits. Further research might explore the differential effects of individual illicit drugs on real-world memory.

Visuospatial working memory impairment in current and previous ecstasy/polydrug users.

OBJECTIVE: Previous research suggests that ecstasy users are impaired in processing visuospatial information. However, for the most part, the deficits observed appear to involve the recall and recognition of complex visual and geometric patterns. The present research sought to determine whether ecstasy use was associated with deficits in serial spatial recall and visuospatial working memory (VSWM). METHODS: Thirty-eight current ecstasy/polydrug users, 16 previous ecstasy/polydrug users and 52 non ecstasy users completed serial simple spatial recall and VSWM tasks. RESULTS: Both the current and previous users of ecstasy exhibited deficits on the VSWM task. Following controls for group differences in aspects of cannabis and cocaine use, the overall group effect fell to just below statistical significance. However, the difference contrast comparing users with nonusers continued to demonstrate a statistically significant ecstasy-related VSWM deficit. CONCLUSIONS: Ecstasy users were impaired in processing visuospatial information especially under conditions of high processing demand. The results are consistent with ecstasy-related impairment either in the short-term posterior parietal and occipital area store or the dorsolateral prefrontal cortex processes, which augment it under conditions of higher processing demands. Further research is needed to pinpoint the actual source of the ecstasy/polydrug-related VSWM deficits that have been observed here and elsewhere.