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

Assessing time-based prospective memory online: A comparison study between laboratory-based and web-based testing

Prospective memory (PM, i.e., the ability to remember and perform future intentions) is assessed mainly within laboratory settings; however, in the last two decades, several studies have started testing PM online. Most part of those studies focused on event-based PM (EBPM), and only a few assessed time-based PM (TBPM), possibly because time keeping is difficult to control or standardise without experimental control. Thus, it is still unclear whether time monitoring patterns in online studies replicate typical patterns obtained in laboratory tasks. In this study, we therefore aimed to investigate whether the behavioural outcome measures obtained from the traditional TBPM paradigm in the laboratory-accuracy and time monitoring-are comparable with an online version in a sample of 101 younger adults. Results showed no significant difference in TBPM performance in the laboratory versus online setting, as well as no difference in time monitoring. However, we found that participants were somewhat faster and more accurate at the ongoing task during the laboratory assessment, but those differences were not related to holding an intention in mind. The findings suggest that, although participants seemed generally more distracted when tested remotely, online assessment yielded similar results in key temporal characteristics and behavioural performance as for the laboratory assessment. The results are discussed in terms of possible conceptual and methodological implications for online testing.

Keeping the Time: The Impact of External Clock-Speed Manipulation on Time-Based Prospective Memory

Several studies have suggested that time monitoring is important for appropriate time-based prospective memory (TBPM). However, it is still unknown if people actively use internal timing processes to monitor the approaching target time, and whether they do so by tracking the duration between clock digits, or by counting and matching the numerical progression of clock ticks' digits with the target time. Therefore, in the present study, we investigated whether a manipulation of the external time affected time monitoring and TBPM performance. In two experiments, participants performed two identical TBPM tasks: a first TBPM block with no clock-speed manipulation followed by a second TBPM block, where the clock-speed was manipulated as faster or slower (experimental conditions) or normal (control condition). The results showed that only participants in the slower clock condition increased time monitoring in the second compared to the first TBPM block (d = 0.42 and 1.70); moreover, particularly in Experiment 2, participants in the faster clock condition checked the clock significantly less frequently than participants in the slower clock (d = -1.70) and in the control condition (d = -0.98), but only during the 4th minute. No effect was found for TBPM performance. Overall, results suggested that people tracked the target time by counting and matching the numerical progression of clock ticks' digits with the target time. The findings are discussed considering the most recent theoretical advancements about the relationship between time perception and TBPM.

The cost of monitoring in time-based prospective memory

Time-based prospective memory (TBPM) involves remembering to perform actions at specific times in the future. Several studies suggest that monetary consequences improve prospective remembering; however, the effect of monetary consequences on strategic time monitoring (i.e., clock-checking behaviour) in TBPM is still unknown. The present study investigated how the monetary costs on clock-checking affected TBPM accuracy and strategic time monitoring. Participants performed an ongoing lexical decision task while carrying out a TBPM task every two minutes. Motivational incentives were manipulated across three experimental conditions: a single-cost condition in which missed TBPM responses led to monetary deductions, a double-cost condition in which both missed responses and time monitoring led to monetary deductions, and a control condition with no monetary deductions. Overall, the findings indicated that monetary costs on clock-checking prompted more parsimonious strategic time monitoring behaviour, which negatively impacted TBPM accuracy. These results emphasize the importance of weighing the motivational aspects involved in strategic monitoring, shedding light on the complex relationship between clock-checking behaviour, its consequences, and TBPM performance.

Aging and time-based prospective memory in the laboratory: a meta-analysis on age-related differences and possible explanatory factors

In older adults' everyday life, time-based prospective memory (TBPM) is relevant as health-related intentions are often part of daily activities. Nonetheless, it is still unclear which task-related factors can potentially moderate the magnitude of age-related differences, such as duration of the PM target time (the time-window within which an individual must complete a given TBPM task), the frequency of the TBPM tasks, and the criterion chosen to compute PM accuracy. The present meta-analysis aimed to quantify age-related differences in laboratory TBPM tasks, and to investigate how specific task-related factors potentially moderate the magnitude of age effects. The results showed that age effects consistently emerged among the studies, with older adults showing lower TBPM performance and checking the clock less often than younger adults, especially for shorter intervals (e.g., ≤ 4 min). Furthermore, the results indicated that the duration of the PM target time interacted with the frequency of the PM task, suggesting that learning effects may attenuate the magnitude of age differences in TBPM performance. The results are discussed in terms of potential implications about the possible cognitive processes involved in TBPM and aging, as well as in terms of robustness of the TBPM laboratory paradigm in aging research.

External Time Monitoring in Time-Based Prospective Memory: An Integrative Framework

We propose a new integrative framework of external time monitoring in prospective memory (PM) tasks and its relation with performance. Starting from existing empirical regularities and our theoretical analysis, the framework predicts that external monitoring in PM tasks comprises a first stage of loose monitoring to keep track of the passage of time, and a subsequent stage of finer-grained monitoring, based on interval reduction, to meet the PM deadline. Following our framework, we predicted and observed in three different datasets (N = 375): (1) a marked increase in external monitoring frequency in the final part of the period of the PM task, well captured by a proportional rate exponential growth function; (2) a positive association between individual compliance with this monitoring pattern and PM performance; (3) a positive relation between monitoring frequency in the time window immediately preceding the PM deadline and PM performance at the individual level; and (4) good individual compliance with an interval reduction pattern in external monitoring, especially in the time window closer to the PM deadline. These results support the proposed integrative framework, which has the potential to foster future research on external monitoring in PM and in other fields of cognitive science.

The Cognitive Mechanism of the Practice Effect of Time-Based Prospective Memory: The Role of Time Estimation

Remembering to perform delayed intentions at a specific time point or period is referred to as time-based prospective memory (TBPM). The practice effect of TBPM is the phenomenon that TBPM performance improves via repeated PM training. In the present study, our main purpose was to explore the cognitive mechanism of the practice effect of TBPM, specifically the role of time estimation in the practice effect. We adopted a simple retrospective component of TBPM (pressing 1 key) in the present study, facilitating a closer look at the role of time estimation. In Experiment 1, the experimental group received 20 TBPM tasks training and some ongoing tasks training, while the control group only received some ongoing tasks training. We found that TBPM and time estimation abilities of experimental group were all better than those of control group. It proved that the practice effect of TBPM was closely related to the improvement of time estimation ability. In Experiment 2, we used time estimation training instead of TBPM training used in Experiment 1. The results of Experiment 2 were basically the same as those of Experiment 1. It further confirmed that time estimation played a key role in the practice effect of TBPM.

The role of time-monitoring behaviour in time-based prospective memory performance in younger and older adults

Time-based prospective memory (TB-PM) is the ability to remember to perform an action at a specific moment in the future. Accurate TB-PM performance requires several cognitive processes that are known to decline in normal ageing. This study aimed to examine associations between TB-PM performance and executive functions and time perception in younger and older adults. TB-PM was assessed with the Virtual Week paradigm. Using a within-subjects experimental manipulation, participants performed TB-PM tasks both when a clock was in constant view and when it was hidden behind a button. Results showed that younger adults performed significantly better than older adults on all TB-PM task types, and checked the clock more often, and more strategically. Clock availability improved TB-PM performance in all participants. Correlational analyses showed that TB-PM accuracy was positively related to clock-checking frequency but unrelated to time perception. Relationships between executive functions and TB-PM differed across age groups as well as TB-PM task types. The findings suggest that different cognitive processes are required for different types of TB-PM tasks and in different ages. These results highlight the importance of considering TB-PM task parameters when investigating the role of cognitive processes in PM performance and their contribution to age-related PM decline.

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.

Self-Reports of Increased Prospective and Retrospective Memory Problems in Adults with Developmental Dyslexia

Short-term and working memory problems in dyslexia are well-documented, but other memory domains have received little empirical scrutiny, despite some evidence to suggest that they might be impaired. Prospective memory is memory for delayed intentions, whilst retrospective memory relates to memory for personally experienced past events. To gain an understanding of subjective everyday memory experience, a self-report measure designed to tap prospective and retrospective memory was administered to 28 adults with dyslexia and 26 IQ-matched adults without dyslexia. Adults with dyslexia reported experiencing significantly more frequent problems with memory than the adults without dyslexia. Group differences were found across seven out of the eight questionnaire scales. Further to these analyses, the participants' own ratings were compared with proxy ratings provided by close associates. The perception of poorer memory abilities in the participants did not differ between respondent types. The self-reported difficulties are, thus, unlikely to be the result of lowered self-esteem or metacognitive awareness. More frequent difficulties with both types of memory would seem, therefore, to be experienced by adults with dyslexia in everyday life. Further laboratory-based research is recommended to explore both memory domains in dyslexia and to identify the cognitive mechanisms by which these problems occur. Copyright © 2016 John Wiley & Sons, Ltd.

Time-based prospective memory difficulties in children with ADHD and the role of time perception and working memory

Time-based prospective memory (PM) is the ability to remember to perform an intended action at a given time in the future. It is a competence that is crucial for effective performance in everyday life and may be one of the main causes of problems for individuals who have difficulty in planning and organizing their life, such as children with attention deficit/hyperactivity disorder (ADHD). This study systematically examines different aspects of time-based PM performance in a task that involves taking an action at a given future time in a group of 23 children with ADHD who were compared with a matched group of typically-developing (TD) children. The children were asked to watch a cartoon and then answer a questionnaire about its content (ongoing task). They were also asked to press a key every 2 minutes while watching the cartoon (PM task). The relationships of time perception and verbal working memory with PM performance were examined by administering appropriate tasks. The results showed that the children with ADHD were less accurate than the TD children in the PM task and exhibited less strategic time-monitoring behavior. Time perception was found to predict PM accuracy, whereas working memory was mainly involved in time-monitoring behavior, but this applied more to the TD group than to the ADHD group, suggesting that children with ADHD are less able to use their cognitive resources when meeting a PM request.

Time-based prospective memory in adults with developmental dyslexia

Prospective memory (PM) is memory for delayed intentions. Despite its importance to everyday life, the few studies on PM function in adults with dyslexia which exist have relied on self-report measures. To determine whether self-reported PM deficits can be measured objectively, laboratory-based PM tasks were administered to 24 adults with dyslexia and 25 age- and IQ-matched adults without dyslexia. Self-report data indicated that people with dyslexia felt that time-based PM (TBPM; requiring responses at certain times in the future) was most problematic for them and so this form of PM was the focus of investigation. Whilst performing the ongoing task from which they were required to break out every 3 min to make a PM-related response, the participants were allowed to make clock checks whenever they wished. The cognitive demands made on ongoing behaviour were manipulated to determine whether loading executive resources had a mediating role in dyslexia-related deficits in PM, resulting in three tasks with varying working memory load. A semi-naturalistic TBPM task was also administered, in which the participants were asked to remind the experimenter to save a data file 40 min after being given this instruction. Dyslexia-related differences were found across all three computerized tasks, regardless of cognitive load. The adults with dyslexia made fewer correct PM responses and also fewer clock checks. On the semi-naturalistic task, the participants with dyslexia were less likely to remember to remind the experimenter to save the file. This is the first study to document PM deficits in dyslexia using objective measures of performance. Since TBPM impairments were found under more naturalistic conditions as well as on computerized tasks, the results have implications for workplace support for adults with dyslexia.

Time-based prospective memory in severe traumatic brain injury patients: the involvement of executive functions and time perception

Prospective memory (PM) is the ability to remember to perform a future action at a specified later time, which is investigated through the use of event-based and time-based tasks. Prior investigations have found that PM is impaired following traumatic brain injury (TBI). However, there is limited information regarding the cognitive functions that mediate TBI and PM performance. Thus, this study investigated time-based PM in TBI patients, and the relationship among time-based PM, time perception, and executive functions. To accomplish this objective, 18 severe TBI patients and 18 healthy matched controls performed a time-based PM task, a time reproduction task, and two executive functions (Stroop and n-back) tasks. While both groups increased their monitoring frequency close to the target time, TBI patients monitored more and were less accurate than healthy controls at the target time confirming the time-based PM dysfunction in these patients. Importantly, executive functions, particularly inhibition and updating abilities, were strongly related to time-based PM performance; both time perception and executive functions are involved in time-based prospective memory in controls, whereas, only executive functions appear to be involved in TBI time-based prospective memory performance.