Prospective memory deficits in Ecstasy users: effects of longer ongoing task delay interval

Factor Structure of the Memory for Intentions Test (MIsT): A Conceptual Replication in Older Adults and People with HIV Disease

OBJECTIVE

The Memory for Intentions Test (MIsT) is a clinical measure of prospective memory that has strong evidence for convergent, discriminative, and ecological validity. This study uses a conceptual replication design to evaluate the latent structure of the MIsT in two parallel samples who commonly experience prospective memory deficits: older adults and people living with HIV disease.

PARTICIPANTS AND METHODS

Study participants included 303 people with HIV disease (ages 18-67) and 267 community-dwelling older adults (ages 50-91). Confirmatory factor analyses of the MIsT were conducted separately in each sample. We evaluated a one-factor model, as well as three two-factor models with the MIsT items loading onto each factor based on cue type, delay interval, or response modality.

RESULTS

The one-factor model provided the best (and most parsimonious) fit to the data in both study samples. All two-factor models also demonstrated good fit statistics, although correlations between the two factors in each model were high and none of the two-factor models provided a significantly better fit than the one-factor model.

CONCLUSIONS

Results of this conceptual replication study provide support for a robust factor structure of the MIsT across older adults and people with HIV disease. A total score for the MIsT provides the most parsimonious solution, although available evidence and theory also support the potential use of subscales (e.g., cue type). Future studies of the MIsT would be useful to determine its psychometrics in different clinical populations and across demographic factors (e.g., race/ethnicity).

Recreational drug use and prospective memory

Prospective memory (PM) impairment in recreational drug users has been documented in recent years. However, most studies on the effects of drugs on PM contain several methodological challenges, such as small sample size (< 100 participants), unrepresentative sample type (e.g., student or patient), short abstinence period (< 7 days), and lack of control of potential confounds (e.g., sleep and IQ). The present study investigated the possible consequences of recreational drug use on prospective memory, using self-report and lab-based prospective memory measures while overcoming the methodological challenges. The sample was composed of 47 non-users (27 females, age range from 18 to 50 +) and 53 drug users (21 females, age range from 18 to 50 +). Recreational drug users reported significantly more deficits in the long-term episodic, short-term habitual, and internally cued PM failures subscales of the Prospective Memory Questionnaire. However, these deficits were eliminated after controlling for covariates (e.g., age, sleep quality, general health, alcohol usage). Recreational drug users also performed worse than non-users in the short-term, long-term, event-based, and time-based PM subscales of the Royal Prince Alfred Prospective Memory Test. These results remained significant after controlling for the covariates. Drug users demonstrated greater impairments on time-based and long-term PM tasks thought to be linked with executive functioning. Taken together, the present study provides further support for recreational drug-related deficits in PM and highlights a dissociation between self-report and lab-based PM measures.

Prospective memory impairment in neurological disorders: implications and management

Prospective memory is a core neurocognitive ability that refers to memory for future intentions, such as remembering to take medications and to switch off appliances. Any breakdown in prospective memory, therefore, has serious implications for the ability to function independently in everyday life. In many neurological disorders, including Parkinson disease and dementia, prospective memory deficits are common even in the earliest stages and typically become more severe with disease progression. Consequently, clinical assessment of prospective memory is of critical importance. This article provides an overview of the various manifestations and neural bases of prospective memory deficits. To facilitate clinical decision-making, validated measures of this construct are identified and their suitability for clinical practice is discussed, focusing in particular on clinical sensitivity and psychometric properties. The article concludes by reviewing the approaches that can be used to rehabilitate different types of prospective memory impairment, and algorithms to guide the evaluation and treatment of these impairments are provided.

The effects of short-term L2 training on components of executive control in Indian bilinguals

This study investigated whether a short training (8 weeks) in the second-language (English) has any facilitative effect on components of executive functions in young adults. A pre-post design was used with two groups of participants: one group (experimental group) of students received English language training for eight weeks, and another group (control group) matched on age and background did not. Executive function tasks (Flanker, Stroop, and color-shape switching task) along with the object naming and working memory tasks were administered before and after the training. We observed that the experimental group demonstrated significant improvement in task switching, working memory capacity, and language skills. Findings from the study provide evidence that short training in second-language can enhance some components of executive functions besides improving language skills in young adult students. This finding contributes to a better understanding of language training and executive function among young adult bilinguals.

Comparing different tests to detect early manifestation of prospective memory decline in aging

Objective: Prospective memory (PM) is the ability to remember to perform future intentions. Previous studies have demonstrated that, compared to a younger cohort, healthy older adults have impairments in PM. Considering the importance of early detection of age-related PM decline, the present study aims to compare the performance of healthy older adults using three well-known PM tests commonly used in clinical settings.Method: In the present study, we tested 70 older adults (65-95 years old) using the Cambridge Prospective Memory Test (CAMPROMPT), the Memory for Intentions Screening Test (MIST) and the Royal Prince Alfred Prospective Memory Test (RPA-ProMem). In order to compare performance across tests and the interaction between age and cues, we performed a linear mixed model with random intercept and random slopes. Moreover, additional mixed models with random intercept were run for analyzing the additional information provided by MIST and RPA-ProMem regarding delay responses, response modality effects and type of errors committed.Results: Our data showed a drop in PM performance as age increased detected by all three tests. Furthermore, CAMPROMPT was the most sensitive test to identify differences in PM for event-and time-based cues, at least for participants with 65-77 years old. When data were analyzed in term of delay responses, participants were more accurate for 2 min delay (MIST) and 30 in delay (RPA-ProMem). Participants were less accurate when response modality was "verbal" compared to "action" (MIST) and made more PM errors as age increased.Conclusions: Overall, the study provides important information regarding age-related PM decline and can help researchers as well as clinicians in deciding the preferred test to evaluate PM performance.

Illegal drug use and prospective memory: A systematic review

Illegal drug use is proposed to interfere with neurobiological functioning by damaging the neurotransmitter communication systems that are believed to be responsible for cognitive abilities, including perception, attention, and memory. This review specifically examined effects of illegal drug use on prospective memory (PM) - memory for future actions. Twenty- seven studies spanning 14 years were included in this review which were divided into two broad categories based on testing methods used: self-report and lab-based testing methods. The quality of the included studies was assessed across five categories: sample type, sample size, abstinence period, testing methods and control for confounding factors. The overall quality of evidence was good for six studies and moderate for sixteen studies and low for five studies. The results from the studies employing self-report were inconsistent as illegal drug users exhibited PM deficits in some studies, but not in others. However, the studies with lab-based testing methods demonstrated more consistent findings with illegal drug users scoring worse than non-users on various PM tests. There were also consistent findings on the link between the dosage of drug taken and level of PM deficit. Based on the literature, there is moderate evidence that illegal drug use impairs PM ability. We recommend that further lab-based studies be conducted to assess dose-response effects on drug-specificity.

The effects of licit and illicit recreational drugs on prospective memory: a meta-analytic review

RATIONALE

There are no recent reports summarising the magnitude of prospective memory (PM) impairments in recreational drug users.

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Non-Dependent and Dependent Daily Cannabis Users Differ in Mental Health but Not Prospective Memory Ability

Research suggests that daily cannabis users have impaired memory for past events, but it is not clear whether they are also impaired in prospective memory (PM) for future events. The present study examined PM in daily cannabis users who were either dependent (n = 18) or non-dependent (n = 18), and compared them with non-using controls (n = 18). The effect of future event simulation (FES) on PM performance was also examined. Participants were matched across groups on age, gender, and highest level of education. The virtual week (VW) was used to objectively assess PM abilities, both at baseline and following FES. Other measures used were: cannabis use variables, immediate and delayed prose recall, phonemic and category fluency, spot-the-word test (premorbid intelligence), Beck Depression Inventory, Beck Anxiety Inventory, and a measure of schizotypy (Oxford-Liverpool Inventory of Feelings and Experiences: unusual experiences subscale). No group differences were found in PM performance on the VW, and FES did not improve PM performance in any group. Dependent cannabis users scored higher on depression, anxiety, and schizotypy than both other groups with non-dependent cannabis users scoring at a similar level to controls. There were no group differences in alcohol use. Findings suggest that when carefully matched on baseline variables, and not differing in premorbid IQ or alcohol use, young, near-daily cannabis users do not differ from non-using controls in PM performance.

A systematic review of prospective memory in HIV disease: from the laboratory to daily life

OBJECTIVE

Prospective memory (PM) is described as the capacity to form and maintain an intention that is executed in response to a specific cue. Neural injury and associated neurocognitive disorders are common among persons living with HIV disease, who might therefore be susceptible to impairment in PM.

METHOD

This literature review utilized a structured qualitative approach to summarize and evaluate our current understanding of PM functioning in people living with HIV disease. 33 studies of PM in HIV+ persons met criteria for inclusion.

RESULTS

Findings showed that HIV is associated with moderate deficits in PM, which appear to be largely independent of commonly observed comorbid factors. The pattern of PM deficits reveals dysregulation of strategic processes that is consistent with the frontal systems pathology and associated executive dysfunction that characterizes HIV-associated neural injury. The literature also suggests that HIV-associated PM deficits present a strong risk of concurrent problems in a wide range of health behaviors (e.g. medication non-adherence) and activities of daily living (e.g. employment). Early attempts to improve PM in HIV disease have revealed that supporting strategic processes might be effective for some individuals.

CONCLUSIONS

HIV-associated PM deficits are common and exert a significant adverse effect on the daily lives and health of infected persons. Much work remains to be done to understand the cognitive architecture of HIV-associated PM deficits and the most efficient means to enhance PM functioning and improve health outcomes in persons living with HIV.

Adults with developmental dyslexia show selective impairments in time-based and self-initiated prospective memory: Self-report and clinical evidence

BACKGROUND

Prospective memory (PM; memory for delayed intentions) would seem to be impaired in dyslexia but evidence is currently limited in scope.

AIMS

There is a need, therefore, firstly, to explore PM under controlled conditions using a broader range of PM tasks than used previously and, secondly, to determine whether objectively measured and self-reported PM problems can be found in the same individuals with dyslexia.

METHODS AND PROCEDURES

The responses of 30 adults with dyslexia were compared with those of 30 IQ-matched adults without dyslexia on a self-report and a clinical measure of PM.

OUTCOMES AND RESULTS

Dyslexia-related deficits were shown on the clinical measure overall and, more particularly, when PM responses had to be made to cues based on time rather than environmental events. Adults with dyslexia were also more likely to forget to carry out an intention under naturalistic conditions 24h later. On the self-report questionnaire, the group with dyslexia reported significantly more frequent problems with PM overall, despite using more techniques to aid their memory. In particular, problems were identified with longer-term PM tasks and PM which had to be self-initiated.

CONCLUSIONS AND IMPLICATIONS

Dyslexia-related PM deficits were found under both laboratory and everyday conditions in the same participants; the first time that this has been demonstrated. These findings support previous experimental research which has highlighted dyslexia-related deficits in PM when the enacting of intentions is based on time cues and/or has to be self-initiated rather than being in prompted by environmental events.

Retrieval cue and delay interval influence the relationship between prospective memory and activities of daily living in older adults

OBJECTIVE

Older adults commonly experience mild declines in everyday functioning and the strategic aspects of prospective memory (PM). This study used multiprocess theory to examine whether the strategic demands of retrieval cue type (event vs. time based) and delay interval length (2 vs. 15 min) influence the relationship between PM and activities of daily living (ADLs) in older adults.

METHOD

Participants included 97 community-dwelling older adults recruited from the Western Australia Participant Pool. Participants were administered the Memory for Intentions Screening Test (MIST) and Prospective and Retrospective Memory Questionnaire (PRMQ) as part of a larger neurocognitive assessment. A knowledgeable informant completed the Activities of Daily Living Questionnaire (ADLQ), from which a cutpoint of ≥ 1 was used to classify participants into "ADL normal" (n = 37) or "mild ADL problems" (n = 60) groups. Repeated measures multivariate analysis of variance (MANOVA) controlling for age was conducted with ADL group as the between-subjects factor and either MIST or PRMQ cue and delay scores as the within-subjects factors.

RESULTS

We observed a significant ADL group by PM interaction on the MIST, with pair-wise analyses showing that the mild ADL problems group performed worse than ADL normal participants on the 15-min time-based scale (p < .001, Cohen's d = 0.71). No other MIST or PRMQ cue-delay variable differed between the two ADL groups (ps > .10).

CONCLUSION

Findings indicate that decrements in strategically demanding cue monitoring and detection over longer PM delays may partly explain older adults' mild problems in everyday functioning. Findings may inform neuropsychological interventions aimed at maintaining ADL independence and enhancing quality of life in older adults.

Multiple obstacles to psychological care from the viewpoint of addiction service users

Purpose

– The purpose of this paper is to explore addiction service users’ experiences of psychological interventions for depression symptoms, with an emphasis on understanding obstacles to engage with treatment.

Design/methodology/approach

– This was a thematic analysis of semi-structured interviews with ten people who took part in a randomised controlled trial of cognitive and behavioural interventions; four of whom never engaged with treatment.

Findings

– Five prominent obstacles to access therapy were: memory deficits, becoming overwhelmed by multiple demands and appointments, being housebound due to fluctuations in mental health problems, tendency to avoid the unfamiliar, and contextual life problems related to deprivation and social conflict.

Research limitations/implications

– The authors note some possible limitations related to overreliance on telephone interviews and interviewers’ field notes. The authors discuss the findings in light of epidemiological research, cognitive, behavioural and motivational enhancement theories.

Practical implications

– The authors propose it is important to recognise and address multiple obstacles to therapy. Offering therapy appointments that are co-located within addiction services and time-contingent to other social/medical interventions may help to address some of these obstacles.

Originality/value

– The present qualitative results complement the prior experimental research and enrich the understanding of how to maximise engagement with psychological interventions.

Quick to Act, Quick to Forget: The Link between Impulsiveness and Prospective Memory

Several traits of impulsiveness (e.g. lack of planning and perseverance, difficulty focusing attention) seem intimately connected to the skills required for successful prospective memory performance. This is the first study to examine whether the various inter–correlated dimensions of impulsiveness are related to problems with prospective memory. Undergraduate students (N = 184) completed the Barratt Impulsiveness Scale 11, the Prospective Memory Questionnaire, the Prospective and Retrospective Memory Questionnaire, and two objective prospective memory tests. Results revealed consistent correlations between the various dimensions of impulsiveness (attentional, motor, non–planning) and self–reported problems with prospective memory. Subsequent regression analyses indicated that attentional impulsiveness is a unique predictor of self–reported problems with internally cued prospective memory, and non–planning impulsiveness is a unique predictor of self–reported problems with episodic and overall prospective memory. Similarly, findings from the objective prospective tests showed that non–planning impulsiveness was related to worse performance on the two prospective memory tests. Whereas non–planning impulsiveness was also related to using fewer prospective memory–aiding strategies, mediation analyses showed that use of these strategies does not account for any of the detected relationships. Because the findings suggest that a failure to plan does not underlie the detected effects, other potential explanations for the relationships are discussed. Copyright © 2013 European Association of Personality Psychology

MDMA administration during adolescence exacerbates MPTP-induced cognitive impairment and neuroinflammation in the hippocampus and prefrontal cortex

RATIONALE

We have recently shown that chronic exposure to 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") of adolescent mice exacerbates dopamine neurotoxicity and neuroinflammatory effects elicited by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the substantia nigra and striatum at adulthood.

OBJECTIVES

The present study investigated whether the amplification of MPTP effects by previous treatment with MDMA extends to the limbic and cortical regions and consequently affects cognitive performance.

METHODS

Mice received MDMA (10 mg/kg, twice a day/twice a week) for 9 weeks, followed by MPTP (20 mg/kg × 4 administrations), starting 2 weeks after MDMA discontinuation. Complement type 3 receptor (CD11b) and glial fibrillary acidic protein (GFAP) were evaluated by immunohistochemistry in both the hippocampus and the medial prefrontal cortex (mPFC) to measure microglia and astroglia activation. These neurochemical evaluations were paired with an assessment of cognitive performance by means of the novel object recognition (NOR) and spontaneous alternation tasks.

RESULTS

MPTP administration to MDMA-pretreated mice elicited a stronger activation of CD11b and GFAP in both the hippocampus and the mPFC compared with either substance administered alone. Furthermore, NOR performance was lower in MDMA-pretreated mice administered MPTP compared with mice that received either substance alone.

CONCLUSIONS

These results demonstrate that MDMA-MPTP negative interactions extend to the limbic and cortical regions and may result in cognitive impairment, providing further evidence that exposure to MDMA may amplify the effects of later neurotoxic insults.

Event-based prospective memory deficits in individuals with high depressive symptomatology: problems controlling attentional resources?

Depression has been found to be related to neurocognitive deficits in areas important to successful prospective memory (PM) performance, including executive function, attention, and retrospective memory. However, research specific to depression and PM has produced a mixed pattern of results. The current study further examined the task conditions in which event-based PM deficits may emerge in individuals with high depressive symptomatology (HDS) relative to individuals with low depressive symptomatology (LDS) and the capacity of HDS individuals to allocate attentional resources to event-based PM tasks. Sixty-four participants (32 HDS, 32 LDS) were required to make a PM response when target words were presented during an ongoing lexical decision task. When the importance of the ongoing task was emphasized, response time costs to the ongoing task, and PM accuracy, did not differ between the HDS and LDS groups. This finding is consistent with previous research demonstrating that event-based PM task accuracy is not always impaired by depression, even when the PM task is resource demanding. When the importance of the PM task was emphasized, costs to the ongoing task further increased for both groups, indicating an increased allocation of attentional resources to the PM task. Crucially, while a corresponding improvement in PM accuracy was observed in the LDS group when the importance of the PM task was emphasized, this was not true for the HDS group. The lack of improved PM accuracy in the HDS group compared with the LDS group despite evidence of increased cognitive resources allocated to PM tasks may have been due to inefficiency in the application of the allocated attention, a dimension likely related to executive function difficulties in depression. Qualitatively different resource allocation patterns may underlie PM monitoring in HDS versus LDS individuals.

Prospective memory impairment and executive dysfunction in prefrontal lobe damaged patients: is there a causal relationship?

BACKGROUND

The prospective memory (PM) construct is aimed at capturing cognitive operations involved in the successful accomplishment of delayed intentions. It is generally agreed that PM impairment occurs in patients with prefrontal lobes damage.

OBJECTIVE

To evaluate if there is a causal role of a deficit of executive abilities (failures of planning, set-shifting, selective attention, or working memory) over the PM impairment.

METHODS

We report a detailed investigation of PM and executive abilities in two patients with posttraumatic damage to prefrontal lobes who complained from a reduced compliance with appointments and daily routines.

RESULTS

Laboratory tests confirmed a difficulty in fulfilling delayed intentions in response to the occurrence of critical events and elapsed time. In one patient, PM impairment was associated with poor performance on tests investigating planning, working memory, and mental shifting. The other patient performed in the normal range on all executive tests.

CONCLUSIONS

Despite the frequent claim of a dependence of PM deficits from executive dysfunction, the reported cases demonstrate that this is not necessarily the case. The results are discussed in the light of current hypotheses relating PM impairment to other deficits that commonly occur as a result of damage to the prefrontal lobes.

"Forgetting to remember" in Huntington's disease: a study of laboratory, semi-naturalistic, and self-perceptions of prospective memory

Prospective memory (PM) is dependent on executive processes known to be impaired in Huntington's disease (HD); however, no study to the authors' knowledge has investigated PM in this group. We examined performance-based, semi-naturalistic, and self-reported PM in 20 individuals diagnosed with mild-moderate HD and 20 demographically similar controls. Relative to controls, HD participants demonstrated significantly lower scores in time-based PM, event-based PM (at a trend level), and the semi-naturalistic PM trial, all of which were marked by omission errors. HD participants demonstrated comparable recognition memory for the PM intentions relative to controls. HD and control participants also showed comparable scores in self-reported PM complaints. The results suggest that HD is associated with deficits in the strategic aspects of PM. HD-associated PM deficits also are evident in real-world situations, which may relate to an apparent meta-memory deficit for PM functioning as indicated by HD participants' overestimation of their PM performance on self-report.

Patterns of prospective memory impairment among individuals with depression: the influence of cue type and delay interval

The present study investigated the impact of cue type and delay interval on prospective memory performance in depressed, compared to non-depressed, individuals using a clinically relevant measure, the Memory for Intentions Screening Test. The depressed group demonstrated impaired performance on time-based, but not event-based, prospective memory tasks relative to the nondepressed group. The depressed group also demonstrated impaired prospective memory on tasks with longer delay intervals (15 min), but not on tasks with shorter delay intervals (2 min). These data support theoretical frameworks that posit that depression is associated with deficits in cognitive initiative (i.e., reduced ability to voluntarily direct attention to relevant tasks) and thus that depressed individuals are susceptible to poor performance on strategically demanding tasks. The results also raise multiple avenues for developing interventions (e.g., implementation intentions) to improve prospective memory performance among individuals with depression, with potential implications for medication and other treatment adherence.

MDMA, serotonergic neurotoxicity, and the diverse functional deficits of recreational 'Ecstasy' users

Serotonergic neurotoxicity following MDMA is well-established in laboratory animals, and neuroimaging studies have found lower serotonin transporter (SERT) binding in abstinent Ecstasy/MDMA users. Serotonin is a modulator for many different psychobiological functions, and this review will summarize the evidence for equivalent functional deficits in recreational users. Declarative memory, prospective memory, and higher cognitive skills are often impaired. Neurocognitive deficits are associated with reduced SERT in the hippocampus, parietal cortex, and prefrontal cortex. EEG and ERP studies have shown localised reductions in brain activity during neurocognitive performance. Deficits in sleep, mood, vision, pain, psychomotor skill, tremor, neurohormonal activity, and psychiatric status, have also been demonstrated. The children of mothers who take Ecstasy/MDMA during pregnancy have developmental problems. These psychobiological deficits are wide-ranging, and occur in functions known to be modulated by serotonin. They are often related to lifetime dosage, with light users showing slight changes, and heavy users displaying more pronounced problems. In summary, abstinent Ecstasy/MDMA users can show deficits in a wide range of biobehavioral functions with a serotonergic component.

A pilot study of prospective memory functioning in early breast cancer survivors

AIMS

To evaluate prospective memory (PM) functioning in early breast cancer (BC) survivors and its association with fatigue and depression.

METHODS

The Memory for Intention Screening Test, the Center for Epidemiologic Studies Depression Scale and the Functional Assessment of Cancer Therapy-Fatigue subscale were administered to 80 patients and 80 aged-matched healthy controls.

RESULTS

Patients performed more poorly than controls on the memory test (p < 0.001) and had a higher rate of impairment (odds ratio = 5.5, p < 0.01). Fatigue mediated the relationship between Group membership and PM performance.

CONCLUSIONS

BC survivors exhibited a clear pattern of PM deficit and fatigue was a major contributor to this deficit. This suggests that a common mechanism may be involved in fatigue symptoms and memory disturbances experienced by patients. Further research is needed to evaluate the role of adjuvant therapy in PM deficits and to explore whether interventions targeted at improving fatigue may also improve memory functioning in BC survivors.

Time-based prospective memory predicts engagement in risk behaviors among substance users: results from clinical and nonclinical samples

Deficits in prospective memory (PM; i.e., enacting previously learned actions at the right occasion) and risky decision-making (i.e., making choices with a high chance of undesirable/dangerous outcomes) are both common among individuals with substance use disorders (SUD). Previous research has raised the possibility of a specific relationship between PM and risk-taking, and the present study aimed to systematically study if PM provides unique variance in the prediction of risky decision-making. Two samples were included: (1) a group of 45 individuals with SUD currently in treatment, and (2) a nonclinical group of 59 university students with high-risk drinking and/or substance use. Regression analyses indicated that time-based, but not event-based, PM predicted increased risky behavior (e.g., risky sexual practices and criminal behaviors) in both groups after controlling for demographic, psychiatric, and substance use variables, as well as other neuropsychological functions. The current findings contribute to the growing literature supporting the role of PM as a predictor of everyday functioning, and suggest that cognitive rehabilitation may be an important avenue of research as an adjunct to traditional substance use treatment, particularly in addressing the potential adverse effects of PM deficits in the implementation of treatment-related homework activities and risk management strategies.

Prospective memory and antiretroviral medication non-adherence in HIV: an analysis of ongoing task delay length using the memory for intentions screening test

Using multi-process framework by McDaniel and Einstein (2000), the current study examined whether the length of prospective memory (PM) delay intervals as measured by the 2- and 15-min subscales of the Memory for Intentions Screening Test (MIST) have differential predictive value for antiretroviral (ARV) adherence. Participants included 74 HIV-infected individuals whose ARV adherence was tracked with an electronic monitoring system. Participants were classified as "adherent" (n = 49) or "non-adherent" (n = 25) based on recorded pill bottle openings of ≥90% of prescribed doses over 30 days. An adherence group by MIST delay interval interaction was observed, such that non-adherent participants had worse performance on the 15-min, but not 2-min delay PM MIST subscales. The observed MIST 15-min delay effects were significantly more pronounced on time- versus event-cued PM trials. Long-delay time-based PM was predictive of non-adherence independent of demographics, mood state, self-reported adherence, and general cognitive functioning. Findings from this clinical study indicate that ARV non-adherence may be particularly associated with deficits in strategic cue monitoring over longer PM delays, which may inform interventions to improve adherence among persons living with HIV infection.

Longer ongoing task delay intervals exacerbate prospective memory deficits in HIV-associated neurocognitive disorders (HAND)

The delay interval between encoding a future intention and detection of the retrieval cue is an essential feature of prospective memory (PM). McDaniel and Einstein's ( 2000 ) multiprocess theory posits that greater demands are placed on strategic monitoring processes as the delay interval lengthens. This hypothesis was examined in HIV-associated neurocognitive disorders (HAND), which are associated with strategic dyscontrol of PM, likely secondary to prefrontostriatal circuit pathology. Seventy-eight seronegative adults and 49 individuals with HAND comprised the study groups, which were comparable with regard to demographic, psychiatric, and substance use factors. As part of a comprehensive neuropsychological evaluation, participants were administered a well-validated PM measure that included short (2-min) and long (15-min) task delay interval scales that utilized a standardized word search as the ongoing task. Results revealed a significant interaction of group and delay interval, with significant effects of HAND on PM at long, but not short, delay. The long-delay PM effect in HAND was driven primarily by deficits in time-based PM and was most strongly associated with markers of executive dysfunction. In concordance with the multiprocess theory, individuals with HAND were disproportionately vulnerable to PM deficits at longer ongoing task delay intervals, which appear to be driven by strategic dyscontrol of PM that is consistent with the preferential disruption of prefrontal systems in neuroAIDS (neurological complications of AIDS). Difficulty with successfully completing PM tasks following a longer delay could manifest in real-world problems, such as medication nonadherence and unemployment, and characterizing this specific deficit may inform remediation strategies.

Prospective memory in substance abusers at treatment entry: associations with education, neuropsychological functioning, and everyday memory lapses

Individuals with substance use disorders (SUDs) commonly report lapses in prospective memory (PM) in their daily lives; however, our understanding of the profile and predictors of laboratory-based PM deficits in SUDs and their associations with everyday PM failures is still very preliminary. The current study examined these important questions using well-validated measures of self-report and laboratory-based PM in a mixed cohort of 53 SUD individuals at treatment entry and 44 healthy adults. Consistent with prior research, the SUD group endorsed significantly more self-cued and environmentally based PM failures in their daily lives. Moreover, the SUD group demonstrated significantly lower time-based PM performance, driven largely by cue detection errors. The effect of SUDs on PM was particularly strong among participants with fewer years of education. Within the SUD cohort, time-based PM was correlated with clinical measures assessing executive functions, retrospective memory, and psychomotor speed. Importantly, time-based PM was uniquely associated with elevated PM failures in daily lives of the SUD participants, independent of current affective distress and other neurocognitive deficits. Findings suggest that individuals with SUD are vulnerable to deficits in PM, which may in turn increase their risk for poorer everyday functioning outcomes (e.g., treatment non-compliance).