Event-based Prospective Memory Performance Research Articles

How do the cognitive processes matter in the event-based preschoolers' prospective memory?

Prospective memory (PM) is the ability to remember to perform an intended action at a specific future moment. The current study examined the impact of age, task focality, and cue salience on PM in children aged 2 to 6 years, based on the multiprocess theory of PM and the executive framework of PM development. Additionally, the study explored the relationship between various cognitive abilities and their association with PM performance. A total of 224 preschool-aged children, aged 2-6, engaged in event-based PM tasks with varying cognitive demands. The tasks were either focal or nonfocal, with salient or nonsalient cues. Additionally, individual differences in cognitive abilities were measured. The results support previous indications that even very young children can successfully complete event-based PM tasks. The accuracy of PM display improved with age, especially between the ages of 3 and 4. Better performance was observed in focal PM tasks compared to nonfocal PM tasks. Additionally, preschoolers' PM performance correlated with various cognitive abilities, including fluid intelligence, retrospective memory, inhibitory control, working memory, and language ability. These correlations varied depending on the child's age and the task's nature. For both focal and nonfocal PM tasks, cognitive abilities partially mediated the relationship between age and PM performance. In summary, this study comprehensively explores the specific roles played by age and fundamental cognitive abilities in event-based PM performance among preschool-aged children.

Lower prospective memory is associated with higher neurocognitive dispersion in two samples of people with HIV: A conceptual replication study.

People living with HIV (PLWH) often experience deficits in the strategic/executive aspects of prospective memory (PM) that can interfere with instrumental activities of daily living. This study used a conceptual replication design to determine whether cognitive intraindividual variability, as measured by dispersion (IIV-dispersion), contributes to PM performance and symptoms among PLWH. Study 1 included 367 PLWH who completed a comprehensive clinical neuropsychological test battery, the Memory for Intentions Test (MIsT), and the Prospective and Retrospective Memory Questionnaire (PRMQ). Study 2 included 79 older PLWH who completed the Cogstate cognitive battery, the Cambridge Prospective Memory Test (CAMPROMPT), an experimental measure of time-based PM, and the PRMQ. In both studies, a mean-adjusted coefficient of variation was derived to measure IIV-dispersion using normative T-scores from the cognitive battery. Higher IIV-dispersion was significantly associated with lower time-based PM performance at small-to-medium effect sizes in both studies (mean r s =-0.30). The relationship between IIV-dispersion and event-based PM performance was comparably small in magnitude in both studies (r s =-0.19, -0.20), but it was only statistically significant in Study 1. IIV-dispersion showed very small, nonsignificant relationships with self-reported PM symptoms in both samples (r s < 0.10). Extending prior work in healthy adults, these findings suggest that variability in performance across a cognitive battery contributes to laboratory-based PM accuracy, but not perceived PM symptoms, among PLWH. Future studies might examine whether daily fluctuations in cognition or other aspects of IIV (e.g., inconsistency) play a role in PM failures in everyday life.

Improving prospective memory in school-aged children: Effects of future thinking and performance predictions

Recently, event-based prospective memory (PM) performance of children has been shown to benefit from different encoding strategies such as imagining the execution of a future PM task (i.e., future thinking) and making performance predictions (i.e., metacognitive monitoring). This study aimed to investigate whether and how these two encoding strategies affect PM performance alone and in combination. For this purpose, 127 children aged 8–11 years were assigned to four encoding conditions: (a) standard, (b) performance predictions, (c) future thinking, and (d) future thinking + performance predictions. The ongoing task performance costs (i.e., attentional monitoring), working memory (WM) span, and metacognitive monitoring judgments, such as task difficulty expectations, performance postdictions, confidence judgments, and strategy use, were also evaluated among participants. The results show that combining future thinking instructions with performance predictions considerably improved children’s PM performance without incurring additional attentional monitoring costs. Moreover, whereas children generally tended to overestimate their PM performance, more realistic lower-performance predictions were related to higher PM scores for children in the combined condition. Finally, age, WM, and strategy use significantly predicted PM performance independent of the encoding condition. This study is the first to demonstrate that combining future thinking instructions with performance predictions enhances children’s PM performance compared with each encoding strategy alone. Moreover, this work is the first to show that by simply imagining the execution of a PM task, children’s prediction accuracy can be improved, which is significantly related to the PM performance advantage.

Longitudinal declines in event-based, but not time-based, prospective memory among community-dwelling older adults

ABSTRACT Age-related deficits in prospective memory (PM) are well established, but it is not known whether PM is stable over time among older adults. In this study, 271 community-dwelling older adults underwent abaseline neuropsychological evaluation and up to three follow-up visits, approximately 2.4 years apart. Mixed effects linear longitudinal models revealed small, but significant linear declines and between-subjects variability in event-based PM performance. There were no changes in performance on measures of time-based PM, retrospective memory, or executive functions. Changes in event-based PM were not associated with age, retrospective memory, executive functions, or everyday functioning. Among older adults, event-based PM appears to be more susceptible to linear declines than does time-based PM, which future research might examine with regard to the possible underlying cognitive mechanisms of cue encoding, monitoring, detection, and retrieval processes.

Catechol-O-Methyltransferase Gene Polymorphisms and the Risk of Chemotherapy-Induced Prospective Memory Impairment in Breast Cancer Patients with Varying Tumor Hormonal Receptor Expression.

BackgroundExisting research evidence indicates that breast cancer patients have different degrees of cognitive dysfunction after chemotherapy, and polymorphisms in 3 genes (catechol-O-methyltransferase, COMT; apolipoprotein E, APOE; and brain-derived neurotrophic factor, BDNF) have been associated with cognitive impairment. However, the role of these 3 gene polymorphisms in modulating cognitive impairment in breast cancer survivors with varying hormonal receptor expression is not clear at present.To explore the effects of genetic polymorphisms in BDNF, APOE, and COMT on the regulation of prospective memory impairments induced by chemotherapy in breast cancer patients with various expression levels of estrogen receptor (ER) and progesterone receptor (PR).Material/MethodsA total of 232 patients with breast cancer (113 with ER−/PR− and 119 with ER+/PR+) were evaluated before and after chemotherapy for cognitive function, including prospective memory. Following previously published sequencing procedures, we assessed 6 single-nucleotide polymorphisms (SNPs), including BDNF (rs6265), APOE (rs429358, rs7412), and COMT (rs165599, rs4680, rs737865).ResultsThe patients showed poorer prospective memory scores after chemotherapy than before chemotherapy. Furthermore, the ER−/PR− group showed poorer event-based prospective memory (EBPM) scores than the ER+/PR+ group (z=−7.831, p<0.01) after chemotherapy. The patients with the COMT rs737865G/G genotype, compared with those with the A/A and A/G genotypes, showed a linear EBPM performance (β=1.499, 95% confidence interval (CI)=1.017~2.211) and were less likely to have memory impairment. In contrast, APOE and BDNF polymorphisms did not influence cognitive performance.ConclusionsThe patterns of hormonal receptor expression may be related to prospective memory impairments induced by chemotherapy in breast cancer patients. Furthermore, the COMT polymorphism (rs737865) was linearly related to the extent of deficits in EBPM and may represent a potential genetic marker of risk for cognitive deficits triggered by chemotherapy in patients with breast cancer.

An investigation of the relations between stress and prospective memory

ABSTRACT Prospective memory (PM), or remembering to perform intentions in the future, has important implications for one’s daily functioning and quality of life. Another common human experience is stress. Despite the significance and ubiquity of both PM and stress, our understanding of the relations between them is limited. The aim of the current study was to further delineate the relations between acute stress, chronic stress, non-focal event-based PM, and time-based PM. The results of the study revealed that acute stress induction after PM intention formation did not contribute to differences in non-focal event-based PM performance or time-based PM performance. However, self-reported chronic stress was significantly correlated with enhanced monitoring and time-based PM. In the present study, participants may have had optimal levels of enduring stress that contributed to enhanced monitoring behaviour (i.e. the prospective component of PM) and the ability to complete time-based intentions.

One-year stability of prospective memory symptoms and performance in aging and HIV disease

ABSTRACTIntroduction: HIV disease and aging can both affect prospective memory (PM), which describes the complex process of executing delayed intentions and plays an essential role in everyday functioning. The current study investigated the course of PM symptoms and performance over approximately one year in younger and older persons with and without HIV disease. Method: Participants included 77 older (>50 years) and 35 younger (<40 years) HIV+ individuals and 44 older and 27 younger seronegative adults. Participants completed the Memory for Intentions Test to measure PM in the laboratory, the Prospective and Retrospective Memory Questionnaire to measure PM symptoms in daily life, and several clinical measures of executive functions and retrospective memory as a part of a comprehensive neurocognitive evaluation at baseline and at 14-month follow-up. Results: Findings showed additive, independent main effects of HIV and aging on time- and event-based PM performance in the laboratory, but no change in PM over time. There were no interactions between time and HIV or age groups. Parallel findings were observed for clinical measures of retrospective memory and executive functions. Older HIV+ adults endorsed the greatest frequency of PM symptoms, but there was no change in PM symptom severity over time and no interactions between time and HIV or age groups. There were no effects of HIV or aging on naturalistic PM performance longitudinally. Conclusion: Overall these findings suggest that PM symptoms and performance in the laboratory are stably impaired over the course of a year in the setting of aging and HIV disease.

THE EFFECT OF EMOTIONAL CUES ON EVENT-BASED PROSPECTIVE MEMORY PERFORMANCE IN OBSESSIVE COMPULSIVE DISORDER

Introduction Prospective memory (PM) is defined as the ability to formulate, retain and carry out intentions, plans and promises at the appropriate time or in the appropriate context. Previous studies found evidence that patients with obsessive compulsive disorder (OCD) beside the executive deficit manifest impairment in various PM tasks (Harris et al., 2010; Racsmany et al., 2011; Yang et al., 2015). Our aim with this study was to investigate the influence of emotional stimuli on event-based PM performance in OCD. Material And Methods Thirteen OCD patients took part in the study. An emotional event-based PM task was administered to each participant under two conditions: (1) a baseline condition in which no PM stimuli occurred and the ongoing trials were presented in three blocks based on the stimulus valence as positive, negative and neutral and a (2) PM condition in which beside the ongoing trials positive, negative and neutral PM stimuli also occurred. There were two arrows, pointing right and left, and one of them was black, the other was white. The order of colours varied randomly. Two pictures also appeared on the screen and were located at equal distances above and below the arrows. Participants in the baseline condition were asked to press the arrow key corresponding to the black arrow (ongoing task). In the PM condition the task was similar, except participants were told to press the up-arrow key if the two pictures above and below the fixation point were the same on any trial, this instruction served as a PM task. Results And Conclusions Based on our preliminary results and analysis it seems that the stimulus valence does not influence significantly the accuracy rate and reaction time scores on PM trials. The emotional cues have no beneficial effect on patients PM performance as suggested in previous findings. Further analysis and the recruitment of a healthy control group are under way.

S72. PRO-SOCIAL PROSPECTIVE MEMORY PERFORMANCE IS ASSOCIATED WITH PLASMA OXYTOCIN LEVEL IN SEXUALLY DIMORPHIC WAY IN FIRST-DEGREE RELATIVES OF SCHIZOPHRENIA

BackgroundProspective memory (PM) in real world is mostly societal and it often involves activities in which the individual has to remember to do something for others, which is also called pro-social PM. The neuropeptide oxytocin has been implicated in social cognition and social interaction in a number of studies. The aim of the present study was to investigate the correlation between pro-social PM performance and plasma oxytocin level in first-episode schizophrenic patients (FES), first-degree relatives (FDRs) of schizophrenia, and healthy controls (HCs). In addition, we also tried to explore the sexually dimorphic feature in the interactions of above-mentioned factors.MethodsForty-six FES patients, 41 non-psychotic FDRs of patients with chronic schizophrenia (unrelated to the FES group) and 54 HCs were studied. Pro-social time-based prospective memory (TBPM) and event-based prospective memory (EBPM) performance were assessed with the Chinese version of the Cambridge Prospective Memory Test (C-CAMPROMPT). A serial of tests reflecting retrospective memory and executive functions were also administrated. Plasma oxytocin levels were determined by radioimmunoassay using a RIA kit.Results(1) There were significant differences in performance between FES, FDRs, and HCs with respect both TBPM and EBPM, even after controlling for age, sex and education level by analysis of covariance (ANCOVA). We found significant group*sex interaction only regarding TBPM (F(2, 133)=4.8, p=0.01). Female HCs performed significantly poorer than male HCs on TBPM (11.1 ± 5.5 vs 14.4 ± 4.8, t=-2.3, p=0.026). However, this sexually dimorphic trend was not seen in either FES (9.0 ± 5.1 vs 7.5 ± 5.1, t=1.0, p=0.34) or FDRs (12.3 ± 3.5 vs 11.1 ± 4.4, t=1.0, p=0.3). (2) A significant group*sex interaction was also revealed with regard to plasma oxytocin level (F(2, 134)=4.1, p=0.018). In HCs, females exhibited significantly higher plasma oxytocin level than males (62.2 ± 28.3 pg/ml vs 44.4 ± 20.9 pg/ml, t=2.5, p=0.015). But this sexually dimorphic feature did not appear in FES (58.3 ± 20.1pg/ml vs 59.6 ± 19.4 pg/ml, t=-0.2, p=0.822) or FDRs (60.4 ± 19.2 pg/ml vs 74.0 ± 46.0 pg/ml, t=-1.2, p=0.230). In addition, there was a significant difference in plasma oxytocin level between the three groups only in male. Post-hoc analyses suggest male FDRs exhibited significant higher plasma oxytocin level than male HCs. (3) After controlling age and education level, partial correlation analysis indicated higher plasma oxytocin levels to be significantly associated with higher TBPM scores in FDRs (r=0.39, p=0.015). In order to determine the origin of this correlation, we further conducted 2 separate partial correlation analyses in males and females, still with age and education level as controlled variables. The correlation between plasma oxytocin level and TBPM remained significant in male FDRs (r=0.5, p=0.021) but disappeared in female FDRs (r=0.2, p=0.434).DiscussionIn the present study, we found the pre-existing sex-specific patterns (as in HCs) of plasma oxytocin level and TBPM were substantially disrupted in FES and FDRs. Moreover, a significant association between plasma oxytocin levels and PM was only found in FDRs, and only male FDRs contribute to this significant association, suggesting oxytocin may play an important role regulating pro-social PM in FDRs in sexually dimorphic way.Longitudinal studies with larger sample size and measurement of oxytocin receptor function and genetic variations should be conducted in the future.

The Effect of Task Duration on Event-Based Prospective Memory: A Multinomial Modeling Approach.

Remembering to perform an action when a specific event occurs is referred to as Event-Based Prospective Memory (EBPM). This study investigated how EBPM performance is affected by task duration by having university students (n = 223) perform an EBPM task that was embedded within an ongoing computer-based color-matching task. For this experiment, we separated the overall task’s duration into the filler task duration and the ongoing task duration. The filler task duration is the length of time between the intention and the beginning of the ongoing task, and the ongoing task duration is the length of time between the beginning of the ongoing task and the appearance of the first Prospective Memory (PM) cue. The filler task duration and ongoing task duration were further divided into three levels: 3, 6, and 9 min. Two factors were then orthogonally manipulated between-subjects using a multinomial processing tree model to separate the effects of different task durations on the two EBPM components. A mediation model was then created to verify whether task duration influences EBPM via self-reminding or discrimination. The results reveal three points. (1) Lengthening the duration of ongoing tasks had a negative effect on EBPM performance while lengthening the duration of the filler task had no significant effect on it. (2) As the filler task was lengthened, both the prospective and retrospective components show a decreasing and then increasing trend. Also, when the ongoing task duration was lengthened, the prospective component decreased while the retrospective component significantly increased. (3) The mediating effect of discrimination between the task duration and EBPM performance was significant. We concluded that different task durations influence EBPM performance through different components with discrimination being the mediator between task duration and EBPM performance.

The effects of ongoing task absorption on event-based prospective memory in preschoolers

The current study applied a 2 × 2 experimental design to investigate the effects of ongoing task absorption on event-based prospective memory performance of children aged 3 and 5 years. Children were required to label pictures as ongoing task but to remember to refrain from picture naming and to respond to the target cues in a different way as the prospective memory task. Two differently absorbing ongoing tasks (high absorbing scenario game task vs. low absorbing computer-based task) were administered. Results indicated that prospective memory performance of 5-year-old children was significantly better than that of 3-year-old children. Ongoing task absorption affected the ongoing task performance of preschoolers, but not overall prospective memory performance. Only the 3-year-olds were negatively affected by high ongoing task absorption, which was not the case for the 5-year-olds. The findings are discussed within the light of the multiprocess theory.

Hypnosis Attenuates Executive Cost of Prospective Memory

Prospective memory is the ability to formulate and carry out actions at the appropriate time or in the appropriate context. This study aimed to identify the effect of hypnosis on prospective memory performance and to analyze the involvement of executive control processes in intention realization in a hypnotically altered state of consciousness. In 1 experiment, manipulating hypnotic instruction in a within-subject fashion, the authors explored the event-based prospective memory performance of 23 volunteers in 3 conditions: baseline, expectation, and execution. The primary result was that executing prospective memory responses, at the same accuracy rate, produced a significantly lower cost of ongoing responses in terms of response latency in the hypnotic state than in wake condition.

The nature of prospective memory deficit in patients with obsessive–compulsive disorder

We comprehensively examined prospective memory (PM) performance in patients with obsessive–compulsive disorder (OCD), and explored the cognitive and psychopathological correlates of PM in this clinical population. Fifty-eight OCD patients and 58 healthy controls were assessed with computer-based PM tasks and related neurocognitive functions, and the participants also reported frequency of PM failures and compulsive behaviours in daily life. OCD patients had intact activity-based PM performance but had lower accuracy in time-based PM and longer reaction time to event-based PM cues compared to healthy controls. Among the neurocognitive functions, both the WCST (perseverative error) and the letter number span correlated with time-based PM. OCD patients reported similar number of PM failures in daily life as controls, which correlated with their intact event-based PM performance, suggesting a generally good insight into their PM functions. Neither clinician-assessed nor self-reported OCD symptoms correlated with PM performance. This study indicates that PM impairment tends to vary with the PM cue types in OCD patients. In addition, certain executive functions (i.e., mental shifting and updating) may contribute to time-based PM impairment in patients with OCD.

Intermittent theta burst stimulation over left BA10 enhances virtual reality-based prospective memory in healthy aged subjects

Prospective memory (PM) refers to a complex cognitive ability that underpins the delayed execution of previously formulated intentions. PM performance declines early in normal aging and this process is accentuated in Alzheimer's disease. The left frontopolar cortex (BA10) has been consistently assigned a major role in PM functioning, but whether it can be noninvasively modulated to enhance PM performance in aged people has not been addressed so far. Here, we investigated the effects of modulating left BA10 by means of theta burst stimulation (TBS), using either excitatory (intermittent TBS), inhibitory (continuous TBS) or control (vertex) TBS in healthy aged subjects. The behavioral effects were assessed using a reliable and ecological virtual reality PM task that included both event- and time-based retrievals. As compared with vertex stimulation, event-based PM performance significantly improved after excitatory stimulation, whereas inhibitory stimulation had no significant effect. Additionally, and across the different types of stimulation, performance for congruent links between the event-based PM cue and the action to be performed was significantly better as compared with incongruent links. In conclusion, intermittent TBS might provide a relevant interventional strategy to counteract the decline of cognitive functions and memory abilities in normal aging.

Dissociation of event-based prospective memory and time-based prospective memory in patients with prostate cancer receiving androgen-deprivation therapy: a neuropsychological study.

The primary purpose of this study was to evaluate the event-based prospective memory (EBPM) and time-based prospective memory (TBPM) in androgen-deprivation therapy (ADT)-induced cognitive impairment in patients with prostate cancer (PC). Participants included PC patients who had undergone ADT (ADT group, n = 43) or patients who did not undergo ADT (non-ADT group, n = 35), as well as age and education-matched healthy controls (HC group, n = 40). All participants were administered with a battery of neuropsychological tests including EBPM and TBPM tasks. Our results indicated that during the EBPM task, the ADT group obtained significantly lower scores than the non-ADT and HC group did, while no significant differences in the TBPM task scores were found among these three groups. Additionally, the ADT group demonstrated significantly lower scores in several cognitive tasks, including attention, memory, and information processing, when compared with the other two groups. This study demonstrated that PC patients receiving ADT may have selective reductions in EBPM performance but unimpaired TBPM performance and that these deficits may result from the changes of function and structure of the pre-frontal cortex induced by ADT.

The relationship between event-based prospective memory and ongoing task performance in chimpanzees (Pan troglodytes).

Prospective memory is remembering to do something at a future time. A growing body of research supports that prospective memory may exist in nonhuman animals, but the methods used to test nonhuman prospective memory differ from those used with humans. The current work tests prospective memory in chimpanzees using a method that closely approximates a typical human paradigm. In these experiments, the prospective memory cue was embedded within an ongoing task. Tokens representing food items could be used in one of two ways: in a matching task with pictures of items (the ongoing task) or to request a food item hidden in a different location at the beginning of the trial. Chimpanzees had to disengage from the ongoing task in order to use the appropriate token to obtain a higher preference food item. In Experiment 1, chimpanzees effectively matched tokens to pictures, when appropriate, and disengaged from the ongoing task when the token matched the hidden item. In Experiment 2, performance did not differ when the target item was either hidden or visible. This suggested no effect of cognitive load on either the prospective memory task or the ongoing task, but performance was near ceiling, which may have contributed to this outcome. In Experiment 3, we created a more challenging version of the task. More errors on the matching task occurred before the prospective memory had been carried out, and this difference seemed to be limited to the hidden condition. This finding parallels results from human studies and suggests that working memory load and prospective memory may have a similar relationship in nonhuman primates.

Prospective memory performance in non-psychotic first-degree relatives of patients with schizophrenia: a controlled study.

ObjectiveWe aimed at investigating prospective memory and its socio-demographic and neurocognitive correlates in non-psychotic, first-degree relatives (FDRs) of patients with schizophrenia compared to patients with first episode schizophrenia (FES), and healthy controls (HCs).MethodsForty-seven FES patients, 50 non-psychotic FDRs (23 offspring and 27 siblings) of patients with chronic schizophrenia (unrelated to the FES group) and 51 HCs were studied. The Chinese version of the Cambridge Prospective Memory Test (C-CAMPROMPT) was used to measure time-based prospective memory (TBPM) and event-based prospective memory (EBPM) performance. Other cognitive functions (involving respective memory and executive functions) were evaluated with standardized tests.ResultsAfter controlling for basic demographic characteristics including age, gender and educational level, there was a significant difference between FDRs, FES and HCs with respect to both TBPM (F(2,142) = 10.4, p<0.001) and EBPM (F(2,142) = 10.8, p<0.001). Multiple linear regression analyses revealed that lower scores of the Hopkins Verbal Learning Test-Revised (HVLT-R) and the STROOP Word-Color Test (SWCT) contributed to TBPM impairment, while lower educational level and higher scores of the Color Trails Test-2 (CTT-2) contributed to EBPM deficit in FDRs.ConclusionsFDRs share similar but attenuated prospective memory impairments with schizophrenia patients, suggesting that prospective memory deficits may represent an endophenotype of schizophrenia.

Rule monitoring ability predicts event-based prospective memory performance in individuals with TBI.

Numerous studies have demonstrated that prospective memory (PM) abilities are impaired following traumatic brain injury (TBI). PM refers to the ability to remember to complete a planned action following a delay. PM post-TBI has been shown to be related to performance on neuropsychological tests of executive functioning and retrospective episodic memory (RM). However, the relative influence of impairments in RM versus executive functioning on PM performance post-TBI remains uninvestigated. In the current study, PM and neuropsychological test performance were examined in 45 persons with a history of moderate to severe TBI at least 1 year before enrollment. Regression analyses examined the relative contributions of RM and executive functioning in the prediction of PM performance on the Rivermead Behavioral Memory Test (RBMT). Results indicated that scores on tests of delayed RM and rule monitoring (i.e., ability to avoid making errors on executive measures) were the strongest predictors of PM. When the interaction between RM impairment and rule monitoring was examined, a positive relationship between PM and rule monitoring was found only in TBI participants with impaired RM. Results suggest that PM performance is dependent upon rule monitoring abilities only when RM is impaired following TBI.

Prospective memory performance of patients with Parkinson's disease depends on shifting aptitude: evidence from cognitive rehabilitation.

This study investigated the effect of cognitive training aimed at improving shifting ability on Parkinson's disease (PD) patients' performance of prospective memory (PM) tasks. Using a double-blind protocol, 17 PD patients were randomly assigned to two experimental arms. In the first arm (n=9) shifting training was administered, and in the second (placebo) arm (n=8), language and respiratory exercises. Both treatments consisted of 12 sessions executed over 4 weeks. PM and shifting measures (i.e., Trail Making Test and Alternate Fluency Test) were administered at T0 (before treatment) and T1 (immediately after treatment). A mixed analysis of variance was applied to the data. To evaluate the effects of treatment, the key effect was the interaction between Group (experimental vs. placebo) and Time of Assessment (T0 vs. T1). This interaction was significant for the accuracy indices of the PM procedure (p<.05) and for the performance parameters of the shifting tasks (p ≤.05). Tukey's HSD tests showed that in all cases passing from T0 to T1 performance significantly improved in the experimental group (in all cases p ≤.02) but remained unchanged in the placebo group (all p consistently>.10). The performance change passing from T0 to T1 on the Alternate Fluency test and the PM procedure was significantly correlated (p<.05). Results show that the cognitive training significantly improved PD patients' event-based PM performance and suggest that their poor PM functioning might be related to reduced shifting abilities.

Impact of inhibitory load on remembering delayed intentions in autism

Objective:Research on prospective memory (PM) in autism spectrum disorders (ASD) is scarce and inconsistent. Differences in results have been attributed to differences in executive control demands of the respective PM tasks. However, so far no study has systematically and experimentally manipulated executive control load. The present study set out to explore the impact of varying inhibitory control demands on PM performance in ASD.Method:Twenty-two adults with ASD and 22 age-, gender- and cognitive ability-matched controls were asked to work on a computerised word categorization task into which an event-based PM task was embedded. In addition, they were required to work on a task that put either low or high load on inhibitory resources.Results:With regards to the event-based PM task, no significant effects emerged. Controls outperformed individuals with ASD on the ongoing task performance and ongoing task performance varied with inhibition load. Similarly, inhibition load affected performance on the inhibition task; here, no group effects were found.Conclusion:Findings suggest spared event-based PM performance in ASD regardless of inhibition load. However, results might be limited by ceiling effects and future studies are needed to investigate to explore inhibition effects using more difficult tasks.