意向保持间隔对时间性前瞻记忆的影响

通过两个实验来探讨意向保持间隔对时间性前瞻记忆的影响。实验一仅通过嵌入前瞻目标的背景任务来操纵保持间隔,实验二通过在背景任务之前加入不同时长的填充任务来改变意向保持间隔。结果发现,(1)背景任务中的保持间隔越长,前瞻记忆成绩越差;(2)背景任务中的保持间隔和填充任务的时长对前瞻记忆的影响存在交互作用。成绩最好的为15min-2min组,最差的为15min-15min组。结果表明,背景任务和填充任务阶段对于个体保持前瞻意向可能有不同的功能。     

Cognitive control processes underlying time-based prospective memory impairment in individuals with high depressive symptomatology

The current study compared time-based prospective memory (PM) for individuals with high depressive symptomatology (HDS) and low depressive symptomatology (LDS). We examined PM accuracy rate, clock-checking frequency, and decrements in ongoing task performance (i.e., costs to ongoing tasks) associated with an embedded time-based PM task. HDS participants demonstrated numerically lower but statistically comparable clock-checking frequency to LDS participants. However, their PM performance was significantly poorer than that of LDS participants. The pattern of observed costs to ongoing tasks and correlational analyses between ongoing task performance and PM accuracy showed that, relative to LDS participants, HDS participants were restricted in their allocation of attentional resources to support PM. We concluded that although HDS and LDS participants externally controlled their time-based PM task performance (i.e., clock-checking) similarly, the HDS participants lacked the cognitive initiative to allocate attentional resources to internally control PM task performance. Such internal control might reflect time-estimation processes, the resources required to maintain the PM task response intention, and/or the ability to coordinate the PM task response with ongoing task demands. To our knowledge, this is the first paper to have examined time-based PM strategies used by HDS individuals beyond clock-checking. The data suggest that interventions that encourage intermittent strategic reviews of PM goals may be beneficial for individuals with high depressive symptomatology.     

Prospective and retrospective memory in normal aging and dementia: an experimental study

Two experiments investigated the effects of normal aging and dementia on laboratory-based prospective memory (PM) tasks. Participants viewed a film for a later recognition memory task. In Experiment 1, they were also required either to say "animal" when an animal appeared in the film (event-based PM task) or to stop a clock every 3 min (time-based PM task). In both tasks, young participants were more successful than older participants, who were, in turn, more successful than patients with Alzheimer's disease (AD). For successful remembering in the time-based task, older participants and AD patients checked the clock more often than did young participants. In Experiment 2, participants were asked to reset a clock either when an animal appeared in the film (unrelated cue-action) or when a clock appeared in the film (related cue-action). Responses were faster in the related condition than in the unrelated condition. Again, there were differences in PM performance between young and older participants, and between older participants and AD patients. The observed deficits were not due to the forgetting of the PM task instructions in either experiment. Retrospective memory (RM) tasks (digit span, sentence span, free recall, and recognition) were more impaired by AD than were the PM tasks. Factor analysis revealed separate factors corresponding to RM and PM.     

Distinct and shared cognitive functions mediate event- and time-based prospective memory impairment in normal ageing

Prospective memory (PM) is the ability to remember to perform an action at a specific point in the future. Regarded as multidimensional, PM involves several cognitive functions that are known to be impaired in normal ageing. In the present study we set out to investigate the cognitive correlates of PM impairment in normal ageing. Manipulating cognitive load, we assessed event- and time-based PM, as well as several cognitive functions, including executive functions, working memory, and retrospective episodic memory, in healthy participants covering the entire adulthood. We found that normal ageing was characterised by PM decline in all conditions and that event-based PM was more sensitive to the effects of ageing than time-based PM. Whatever the conditions, PM was linked to inhibition and processing speed. However, while event-based PM was mainly mediated by binding and retrospective memory processes, time-based PM was mainly related to inhibition. The only distinction between high- and low-load PM cognitive correlates lies in an additional, but marginal, correlation between updating and the high-load PM condition. The association of distinct cognitive functions, as well as shared mechanisms with event- and time-based PM, confirm that each type of PM relies on a different set of processes.     

Distinct and shared cognitive functions mediate event- and time-based prospective memory impairment in normal ageing

Prospective memory (PM) is the ability to remember to perform an action at a specific point in the future. Regarded as multidimensional, PM involves several cognitive functions that are known to be impaired in normal ageing. In the present study we set out to investigate the cognitive correlates of PM impairment in normal ageing. Manipulating cognitive load, we assessed event- and time-based PM, as well as several cognitive functions, including executive functions, working memory, and retrospective episodic memory, in healthy participants covering the entire adulthood. We found that normal ageing was characterised by PM decline in all conditions and that event-based PM was more sensitive to the effects of ageing than time-based PM. Whatever the conditions, PM was linked to inhibition and processing speed. However, while event-based PM was mainly mediated by binding and retrospective memory processes, time-based PM was mainly related to inhibition. The only distinction between high- and low-load PM cognitive correlates lies in an additional, but marginal, correlation between updating and the high-load PM condition. The association of distinct cognitive functions, as well as shared mechanisms with event- and time-based PM, confirm that each type of PM relies on a different set of processes.     

Motivation,depression, and naturalistic time-based prospective remembering

This study investigated the effect of a motivational manipulation on naturalistic time-based prospective memory (PM) task performance. The association between depression and PM task performance was also investigated. First-year psychology students were required to send mobile phone text messages (SMSs) at a specific time 3 days and 6 days after an initial meeting. During the delay period participants recorded details of the retrieval whenever they remembered the SMS task. Participants given the incentive of extra course credit (motivation condition) outperformed their counterparts on the PM tasks, and showed a greater increase in the reported frequency of self-initiated retrievals on target days. Depression was negatively correlated with PM task performance. The findings suggest that motivational instructions impact the controlled processes underlying PM.     

Time-based prospective remembering: Interference and facilitation in a dual task

The aim of this study was to analyse prospective memory behaviour when people have to fulfil two different intentions whose retention intervals partially overlapped. More specifically, the purpose of the study was to explore the effects of a secondary PM task (either time-based or event-based) on performance of a main time-based PM task. Four embedded conditions were tested: two event-based ones and two time-based ones. The time- and event-based interpolated tasks differed in how closely their target time was to the 20-minute response required by the main time-based task (16th and 19th min., respectively). The results indicated that when a main time-based prospective memory task shares a portion of the retention interval with a second time-based prospective task, this overlapping facilitated performance on the main task. However, the interpolated tasks appeared to be affected by the moment in which they were administered during the execution of the main time-based task. More specifically, a decrease in the interpolated task performance was observed when this was time-based and had to be executed very closely to the target time of the main task. On the contrary, when the two tasks were different (event-based vs. time-based), there was neither interference, nor facilitation.     

Cognitive load and task condition in event- and time-based prospective memory: an experimental investigation

Prospective memory is memory for the realization of delayed intention. Researchers distinguish 2 kinds of prospective memory: event- and time-based (G. O. Einstein & M. A. McDaniel, 1990). Taking that distinction into account, the present authors explored participants' comparative performance under event- and time-based tasks. In an experimental study of 80 participants, the authors investigated the roles of cognitive load and task condition in prospective memory. Cognitive load (low vs. high) and task condition (event- vs. time-based task) were the independent variables. Accuracy in prospective memory was the dependent variable. Results showed significant differential effects under event- and time-based tasks. However, the effect of cognitive load was more detrimental in time-based prospective memory. Results also revealed that time monitoring is critical in successful performance of time estimation and so in time-based prospective memory. Similarly, participants' better performance on the event-based prospective memory task showed that they acted on the basis of environment cues. Event-based prospective memory was environmentally cued; time-based prospective memory required self-initiation.     

Time-based and event-based prospective memory across adulthood: underlying mechanisms and differential costs on the ongoing task

The authors investigated the phenomenon that performance in an ongoing task declines when individuals must carry out a prospective memory (PM) task. This effect is referred to as the PM interference effect. The authors examined whether the PM interference effect differs between event-based and time-based PM tasks and whether it is increased among the elderly. The authors also investigated adult age differences in PM performance and the potential underlying mechanisms of the age deficits in PM. They found that the PM interference effect was greater in event-based than in time-based tasks. However, aging was not associated with an increase in PM interference effects. Age differences in PM performance were more exaggerated in time-based than event-based PM, but they were not mediated by age differences in traditional cognitive ability measures. In time-based PM, age showed a unique adverse effect even after controlling for the ability to externally monitor the time, leading to the possibility that aging disrupts time-based PM because of deficits in internally processing the time.     

The Duration and Intensity of the Exposure Light as Factors in Determining the Course of the Subsequent Dark-Adaptation: I. the Matching Method

The authors investigated the phenomenon that performance in an ongoing task declines when individuals must carry out a prospective memory (PM) task. This effect is referred to as the PM interference effect. The authors examined whether the PM interference effect differs between event-based and time-based PM tasks and whether it is increased among the elderly. The authors also investigated adult age differences in PM performance and the potential underlying mechanisms of the age deficits in PM. They found that the PM interference effect was greater in event-based than in time-based tasks. However, aging was not associated with an increase in PM interference effects. Age differences in PM performance were more exaggerated in time-based than event-based PM, but they were not mediated by age differences in traditional cognitive ability measures. In time-based PM, age showed a unique adverse effect even after controlling for the ability to externally monitor the time, leading to the possibility that aging disrupts time-based PM because of deficits in internally processing the time.     

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.     

Effects of sad mood on time-based prospective memory

Very little is known about the influence of emotional factors on prospective memory (PM) performance. We used a mood induction (neutral or sad) to examine the effects of sad mood on time-based PM performance. Based on Ellis and Ashbrook's (1988) resource allocation model, we hypothesised an adverse effect of sad mood on PM performance. Results revealed that participants who responded to the sad mood induction procedure showed reduced PM performance that mainly resulted from a decreased timeliness of PM responses, but only in the first half of the task. Mood effects on PM could be explained in terms of reduced and less accurate monitoring. Implications for concepts of PM and the assessment of emotional after-effects are discussed.     

Prospective memory, emotional valence and ageing

Emotional factors have been found to be an important influence on memory. The current study investigated the influence of emotional salience and age on a laboratory measure of prospective memory (PM); Virtual Week. Thirty young and 30 old adults completed Virtual Week, in which the emotional salience of the tasks at encoding was manipulated to be positive, negative or neutral in content. For event-based, but not time-based tasks, positivity enhancement in both age groups was seen, with a greater number of positive PM tasks being performed relative to neutral tasks. There was no negativity enhancement effect. Older adults showed generally poorer levels of PM, but they also demonstrated greater beneficial effects of positive valence compared to young. These effects of emotion on PM accuracy do not appear to reflect the retrospective component of the task as a different pattern of emotion effects was seen on the recall of PM content. Results indicate that older adults' difficulties in prospective remembering can be reduced where the tasks to be remembered are positive.     

Performance benefits of depression: sequential decision making in a healthy sample and a clinically depressed sample

Previous research reported conflicting results concerning the influence of depression on cognitive task performance. Whereas some studies reported that depression enhances performance, other studies reported negative or null effects. These discrepant findings appear to result from task variation, as well as the severity and treatment status of participant depression. To better understand these moderating factors, we study the performance of individuals-in a complex sequential decision task similar to the secretary problem-who are nondepressed, depressed, and recovering from a major depressive episode. We find that depressed individuals perform better than do nondepressed individuals. Formal modeling of participants' decision strategies suggested that acutely depressed participants had higher thresholds for accepting options and made better choices than either healthy participants or those recovering from depression.     

Mental state decoding in past major depression: Effect of sad versus happy mood induction

Individuals with mild depression show an enhanced ability to read or “decode” others' mental states. The goal of the present study was to investigate whether this pattern of performance is related specifically to the pathology of depression or whether it is simply a feature of the transient dysphoric state. Forty-one undergraduates with a previous episode of major depression and 52 undergraduates with no depression history participated in a mental state decoding task following a sad versus happy mood induction. Previously depressed participants were significantly more accurate in their mental state judgements than were the never-depressed participants, suggesting that enhanced mental state decoding may be a specific feature of depression in remission. Furthermore, previously depressed participants whose positive mood increased in response to the happy mood induction showed a poorer level of performance on the task, similar to that observed in the never-depressed group. Thus, a happy mood may have induced a somewhat less accurate, but perhaps more adaptive, approach to processing social information. These findings were robust after controlling for current level of depression and anxiety symptoms, intensity of response to the mood induction, response times, and performance on a control task.     

Comparing time-based and event-based prospective memory over short delays

The current study compared monitoring in time- and event-based prospective memory (PM). Time- and event-based non-focal task instructions were given after a baseline block of a lexical decision ongoing task. Delay between instruction and presentation of PM cue/time was manipulated between-subjects to examine monitoring across short delays (1–6?min). Longer delays decreased performance in the event-based task, but not in the time-based task. This accuracy decline was accompanied by a decline in monitoring (as measured by PM cost to the ongoing task in the trials immediately before the PM cue was presented) between the 1 and 3?min delays. Monitoring was only evident for the time-based task at the 6?min delay as measured by PM cost to the ongoing task. Clock checks were also not affected by delay, but did increase in frequency as the response time neared. These results suggest that delay from the time of intention formation decreases both accuracy and monitoring in event-based tasks, but does not decrease accuracy or monitoring in time-based tasks.     

Time-related processes in time-based prospective memory and in time-interval production

Time-based prospective memory tasks require the retrieval of previously formed plans (e.g., call me on my mobile phone) either at a specified time (e.g., at 3 p.m.) or after a specified period of time has elapsed (e.g., in 3 min). In the present study, we investigated whether the same time-related processes are recruited for a short-duration time-based prospective memory task and for a time-interval production task. In a dual-task paradigm, we required young adult participants to make category-membership decisions, while they were simultaneously engaged either in a time-based prospective memory tasks or in a time-interval production task. Under one set of conditions, participants were instructed to allocate attention equally to the two tasks, whereas in another set of conditions, they allocated attention primarily to the time-relevant task. The findings revealed that time estimates were not affected by the attention allocation manipulation, although it influenced performance on the concurrent category membership decision making task, and as expected time estimates were more accurate on the prospective memory task than on the time-production task. Based on the preponderance of the findings, we suggest that timing is managed by different mechanisms and/or strategies on time-interval production tasks and on short-duration time-based prospective memory tasks.     

The impact of cognitive control on children’s goal monitoring in a time-based prospective memory task

The present study investigated whether developmental changes in cognitive control may underlie improvements of time-based prospective memory. Five-, 7-, 9-, and 11-year-olds (N = 166) completed a driving simulation task (ongoing task) in which they had to refuel their vehicle at specific points in time (PM task). The availability of cognitive control resources was experimentally manipulated by imposing a secondary task that required divided attention. Children completed the driving simulation task both in a full-attention condition and a divided-attention condition where they had to carry out a secondary task. Results revealed that older children performed better than younger children on the ongoing task and PM task. Children performed worse on the ongoing and PM tasks in the divided-attention condition compared to the full-attention condition. With respect to time monitoring in the final interval prior to the PM target, divided attention interacted with age such that older children’s time monitoring was more negatively affected by the secondary task compared to younger children. Results are discussed in terms of developmental shifts from reactive to proactive monitoring strategies.     

Implicit memory and depression: An analysis of perceptual and conceptual processes

A small number of studies have reported impaired explicit memory and intact implicit memory performance in participants classified as depressed. In the present study we examined this finding taking account of the distinction between datadriven and conceptually driven processing. The performance of participants diagnosed with depression was examined on implicit and explicit memory tasks which were designed to tap either predominantly perceptual or conceptual processes. Depressed participants demonstrated performance deficits on both the implicit and explicit conceptual tasks (category association and free recall, respectively) but showed intact performance in the implicit perceptual task (word-fragment completion). These results suggest that people with severe depression show deficits in conceptual processing and that this deficit occurs under both explicit and implicit task instructions.     

The relationship between depression and smoking in adolescents

The literature suggests that smokers are more likely to be depressed, while people who are depressed are more likely to smoke. The purpose of the present study was to determine the strength of the relationship between smoking, depression, intention to smoke, and several psychosocial and environmental factors. The participants (98 high school and college students aged 16 to 19 years) completed a paper-and-pencil questionnaire consisting of the Multiscore Depression Inventory (MDI) and items regarding smoking behavior as well as psychosocial and environmental factors. Correlation, stepwise regression, and discriminant analyses were then conducted. It was found that participants were more likely to smoke if their parents smoked, if their scores on the MDI indicated instrumental helplessness and social isolation/withdrawal, or if they were older. Participants were more likely to state intention to smoke in the future if they had MDI scores indicating instrumental helplessness, if they were older, if their parents smoked, if their MDI scores indicated social intro-version, or if they resided with a guardian. Participants were also more likely to have smoked for more years if their parents smoked or if their scores on the MDI indicated instrumental helplessness. Further, participants were more likely to have scores on the MDI indicative of higher depression levels if they had low grades or if their parents smoked.