Multiprocess Framework Research Articles

Effect of expectations and retention interval on prospective person memory and vigilance

ABSTRACT The present research examined the role of expectations, delay and ongoing task on prospective person memory. Participants (N = 561) studied six mock missing person posters and were told that they had either a low chance or a high chance of encountering the missing persons. Participants were told to press the ‘h’ key if one of the persons was encountered. Participants engaged in a grocery store task immediately after studying the posters or after a five-minute delay. The grocery store task included photographs of 44 individuals, including one of the ‘missing persons’. During the grocery store task, participants either engaged in an attention demanding ongoing activity (i.e. looking for four items from a shopping list) or were able to devote themselves solely to looking for the missing persons. Expectations of encounter increased both correct and incorrect sightings, effects that were more pronounced after the five-minute delay. The presence of the ongoing task had no significant effect on sighting rates. Results are discussed in terms of the multiprocess model [McDaniel, M. A., & Einstein, G. O. (2000). Strategic and automatic processes in prospective memory retrieval: A multiprocess framework. Applied Cognitive Psychology, 14(7), S127–S144 .] and the preparatory attention and memory process model [Smith, R. E. (2003). The cost of remembering to remember in event-based prospective memory: Investigating the capacity demands of delayed intention performance. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29(3), 347–361.] of prospective memory. We also discuss applications of these findings to missing person investigations.

Do emotionally salient cues improve prospective memory performance in children and adolescents with autism?

BackgroundProspective memory (PM) describes the ability to initiate and perform a planned action after a delay. Previous studies suggest reduced PM in autism spectrum disorder (ASD); especially when tasks put high demands on executive control resources. Increasing cue salience by presenting emotional cues improves PM performance in non-autistic populations. AimsTo explore whether children with ASD, whose processing of emotionally connoted information might differ from that of typically developing children, may also benefit from this type of salience in PM tasks. Methods and proceduresTwenty-five children with and 25 children without ASD completed a 1-back ongoing task into which an event-based PM task was embedded. Emotional salience of PM cues was varied. Outcomes and resultsChildren with ASD performed as well as children without ASD on the PM task and equally benefited from emotionally salient cues. Specifically, negative cues increased PM performance compared to neutral cues in both groups Conclusions and implicationsThe findings are consistent with the multiprocess framework which postulates that salient PM cues increase performance by promoting automatic intention retrieval and reducing executive control demands. Children with ASD seem to show similar comprehension and accessibility to emotional cues as typically developing children.

A multi process value-based reinforcement learning environment framework for adaptive traffic signal control

Realising adaptive traffic signal control (ATSC) through reinforcement learning (RL) is an important means to easetraffic congestion. This paper finds the computing power of the central processing unit (CPU) cannot fully usedwhen Simulation of Urban MObility (SUMO) is used as an environment simulator for RL. We propose a multi-process framework under value-basedRL. First, we propose a shared memory mechanism to improve exploration efficiency. Second, we use the weight sharing mechanism to solve the problem of asynchronous multi-process agents. We also explained the reason shared memory in ATSC does not lead to early local optima of the agent. We have verified in experiments the sampling efficiency of the 10-process method is 8.259 times that of the single process. The sampling efficiency of the 20-process method is 13.409 times that of the single process. Moreover, the agent can also converge to the optimal solution.

Salient cues facilitate automatic processes in prospective memory.

Salient cues can improve prospective memory performance. This effect is usually explained through the multiprocess framework, which suggests that salient cues recruit more automatic processes and require fewer cognitive resources than nonsalient cues. However, this explanation lacks direct empirical support, as the accuracy and response time data obtained in behavioral experiments are inadequate for providing an index to indicate the extent to which cognitive resources are recruited. To overcome this difficulty, the present study aimed to use the event-related potentials (ERP) technique to investigate the neurocognitive differences between the processing of salient and nonsalient prospective memory cues and verify whether salient cues facilitate automatic processes. Two experimental conditions were designed to manipulate the salience of prospective memory cues. During an ongoing task, participants were required to detect the word 'apple' (nonsalient prospective memory cue condition) or the red words (salient prospective memory cue condition). The results showed that the nonsalient prospective memory trials elicited sustained larger amplitudes than ongoing trials, whereas the salient prospective memory trials elicited sustained smaller amplitudes than ongoing trials, suggesting that the processing of salient prospective memory cues requires fewer cognitive resources compared to the nonsalient prospective memory cues. Moreover, resource-demanding ERP components were elicited in the processing of nonsalient prospective memory cues, but salient prospective memory cues were not. These results demonstrate that salient cues may facilitate automatic processes in prospective memory.

Wait a second . . . Boundary conditions on delayed responding theories of prospective memory.

Research suggests that forcing participants to withhold responding for as brief as 600 ms eliminates one of the most reliable findings in prospective memory (PM): the cue focality effect. This result undermines the conventional view that controlled attentional monitoring processes support PM, and instead suggests that cue detection results from increased response thresholds that allow more time for PM information to accumulate. Given the significance of such findings, it is critical to examine the generalizability of the delay mechanism. Experiments 1-4 examined boundary conditions of the delay theory of PM, whereas Experiment 5 more directly tested contrasting theoretical predictions from monitoring theory (e.g., multiprocess framework) and delay theory. Using the same (Experiment 1) or conceptually similar (Experiment 2) delay procedure and identical cues (nonfocal "tor" intention) from the original study failed to show any influence of delay on performance. Using a different nonfocal intention (first letter "S") similarly did not influence performance (Experiment 3), and the difference between focal and nonfocal cue detection was never completely eliminated even with delays as long as 2,500 ms (Experiment 4). Experiment 5 did find the anticipated reduction in the focality effect with increased delays with a larger sample (n = 249). However, the focality effect was not moderated by attention control ability despite the fact that participants with impoverished attention control should benefit most from the delay procedure. These results suggest that any theory of PM that considers only a delay mechanism may not fully capture the dynamic attention processes that support cue detection. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Prospective memory and working memory in comparison. New experimental paradigms

Aim of the study: Prospective memory (PM) is a cognitive high load activity. Two main models showed the relation between working memory (WM) and PM. The preparatory attentional and memory processes model (PAM) posits an interdependence between WM and PM; while, the multiprocess framework assumes independence between these two functions.Materials and methods: With the aim to investigate this relation, two tasks were administered to a sample of 21 healthy participants. The first task (arithmetic) required low cognitive and WM load together with a prospective task, the second (PASAT) required high cognitive and WM load together with a prospective switching task. The prospective task included two modalities of administration: based on a sound cue (event-based) or at a given moment (time-based).Results: PM accuracy was influenced by WM only when paired to complex tasks that require high cognitive load on WM and active PM self-retrieval processes (time-PASAT).Conclusions: These results support partial independence between these two mechanisms.

Retrieval in prospective memory: Multiple processes or just delay?

In prospective memory (PM) research, a common finding is that PM accuracy is greater using focal, rather than nonfocal, cues. Under the multiprocess framework, the high PM performance for focal cues (cues that facilitate noticing of the target), often in the absence of task interference, reflects people's ability to rely on spontaneous retrieval processes. By contrast, nonfocal cues (cues that do not facilitate noticing) require monitoring. A competing explanation suggests that a single process underlies focal versus nonfocal PM: People adjust their delay in ongoing responding to allow enough time for PM information to reach awareness (delay theory). Participants' lower nonfocal performance arises because they fail to delay responding to a sufficient degree; with focal cues, the PM information accumulation rate is fast enough that no delay is necessary (and thus most everyone performs well). We sought to improve nonfocal PM performance by pairing a PM task with fast information accumulation to an ongoing task for which the requisite information accumulated more slowly. Reasoning from delay theory, we expected PM accuracy levels in this nonfocal PM task to approximate that observed in a focal PM task (for which the PM tasks were identical). In contrast to this expectation, the focal condition displayed significantly higher PM accuracy (despite demonstrating a reliably shorter response delay). In light of these findings, we concluded that the multiprocess interpretation is favoured.

Prospective memory in autism: theory and literature review

Objective: The current article set out to review all research conducted to date investigating prospective memory (PM) in autism. Method: All studies on PM in autism are first described, followed by a critical review and discussion of experimental findings within the multiprocess framework. PM in autism is then considered through an embodied predictive-coding account of autism. Results: Overall, despite somewhat inconsistent methodologies, a general deficit in PM in autism is observed, with evidence mostly in line with the multiprocess framework. That is, for tasks that are high in cognitive and attentional demand (e.g. time-based tasks; event-based cues of non-focality or low salience) PM performance of autistic participants is impaired. Building upon previous work in predictive-coding, and the way in which expected precision modulates attention, we postulate mechanisms that underpin PM and the potential deficits seen in autism. Furthermore, a unifying predictive-coding account of autism is extended under embodied predictive-coding models, to show how a predictive-coding impairment accounts not only for characteristic autistic difficulties, but also for commonly found differences in autistic movement. Conclusions: We show how differences in perception and action, core to the development of autism, lead directly to problems seen in PM. Using this link between movement and PM, we then put forward a number of holistic, embodied interventions to support PM in autism.

Implementation of the ATLAS trigger within the multi-threaded software framework AthenaMT

We present an implementation of the ATLAS High Level Trigger, HLT, that provides parallel execution of trigger algorithms within the ATLAS multithreaded software framework, AthenaMT. This development will enable the ATLAS HLT to meet future challenges due to the evolution of computing hardware and upgrades of the Large Hadron Collider, LHC, and ATLAS Detector. During the LHC data-taking period starting in 2021, luminosity will reach up to three times the original design value. Luminosity will increase further, to up to 7.5 times the design value, in 2026 following LHC and ATLAS upgrades. This includes an upgrade of the ATLAS trigger architecture that will result in an increase in the HLT input rate by a factor of 4 to 10 compared to the current maximum rate of 100 kHz. The current ATLAS multiprocess framework, AthenaMP, manages a number of processes that each execute algorithms sequentially for different events. AthenaMT will provide a fully multi-threaded environment that will additionally enable concurrent execution of algorithms within an event. This has the potential to significantly reduce the memory footprint on future manycore devices. An additional benefit of the HLT implementation within AthenaMT is that it facilitates the integration of offline code into the HLT. The trigger must retain high rejection in the face of increasing numbers of pileup collisions. This will be achieved by greater use of offline algorithms that are designed to maximize the discrimination of signal from background. Therefore a unification of the HLT and offline reconstruction software environment is required. This has been achieved while at the same time retaining important HLT-specific optimisations that minimize the computation performed to reach a trigger decision. Such optimizations include early event rejection and reconstruction within restricted geometrical regions. We report on an HLT prototype in which the need for HLT-specific components has been reduced to a minimum. Promising results have been obtained with a prototype that includes the key elements of trigger functionality including regional reconstruction and early event rejection. We report on the first experience of migrating trigger selections to this new framework and present the next steps towards a full implementation of the ATLAS trigger.

The Dynamic Interplay Between Bottom-Up and Top-Down Processes Supporting Prospective Remembering

Like many dual process theories in the psychological sciences, existing models of prospective memory (i.e., remembering to execute future intentions) emphasize the role of singular top-down or bottom-up processes that act in isolation. We argue that top-down and bottom-up processes are interconnected and dynamically interact to support prospective memory. We elaborate on this dynamic multiprocess framework by focusing on recent behavioral, neuroimaging, and eye-tracking research that demonstrated the dynamic nature of monitoring (top-down) and spontaneous retrieval (bottom-up) processes in relation to contextual factors, metacognition, and individual differences. We conclude that identifying how dual processes interact with environmental and individual difference factors is crucial for advancing understanding of cognition and behavior.

Optimal Multi-process Control of a Two Vortex Driven Particle in the Plane

This article concerns the optimal motion control of a particle moving in a two dimensional fluid whose dynamics are given by a vector field defined, in any time interval, by two point vortices whose circulation decay exponentially in time with a given constant rate. The control action is exercised by generating one vortex - specified by its location and respective circulation - at a chosen time, and by varying the exposure of the particle to each one of the vortices in continuum time. A control multi-process framework is chosen in order to derive necessary conditions of optimality in the form of a Maximum Principle of Pontryagin. These conditions provide relations that suffice to fully determine the optimal control process.

Semantic Processing as a Significant Factor in Non-Focal Prospective Memory Cues

The aim of the current study was to explore the impact of cue focality and semantic task-appropriate processing on prospective memory (PM) performance and whether this potential effect would be moderated by differences in ongoing task demands. A 3 X 2 mixed factorial design was used where cue focality (focal, semantic non-focal, nonsemantic non-focal) was manipulated within-participants, and ongoing task demands (high, low demands) were manipulated between-participants. A significant effect of focality was identified, where semantic non-focal cues have produced the lowest level of PM performance. Nevertheless, this effect was not moderated by ongoing task demands, which have also not affected PM performance independently. PM results are discussed in the light of the multi-process framework, arguing that semantic non-focal cues might have been perceived by the participants as less demanding, hence failing to engage controlled monitoring processes, which might have supported PM performance in such contexts.

Development of a Next Generation Concurrent Framework for the ATLAS Experiment

The ATLAS experiment has successfully used its Gaudi/Athena software framework for data taking and analysis during the first LHC run, with billions of events successfully processed. However, the design of Gaudi/Athena dates from early 2000 and the software and the physics code has been written using a single threaded, serial design. This programming model has increasing difficulty in exploiting the potential of current CPUs, which offer their best performance only through taking full advantage of multiple cores and wide vector registers. Future CPU evolution will intensify this trend, with core counts increasing and memory per core falling. With current memory consumption for 64 bit ATLAS reconstruction in a high luminosity environment approaching 4GB, it will become impossible to fully occupy all cores in a machine without exhausting available memory. However, since maximizing performance per watt will be a key metric, a mechanism must be found to use all cores as efficiently as possible.In this paper we report on our progress with a practical demonstration of the use of multithreading in the ATLAS reconstruction software, using the GaudiHive framework. We have expanded support to Calorimeter, Inner Detector, and Tracking code, discussing what changes were necessary in order to allow the serially designed ATLAS code to run, both to the framework and to the tools and algorithms used. We report on both the performance gains, and what general lessons were learned about the code patterns that had been employed in the software and which patterns were identified as particularly problematic for multi-threading. We also present our findings on implementing a hybrid multi-threaded / multi-process framework, to take advantage of the strengths of each type of concurrency, while avoiding some of their corresponding limitations.

Running ATLAS workloads within massively parallel distributed applications using Athena Multi-Process framework (AthenaMP)

AthenaMP is a multi-process version of the ATLAS reconstruction, simulation and data analysis framework Athena. By leveraging Linux fork and copy-on-write mechanisms, it allows for sharing of memory pages between event processors running on the same compute node with little to no change in the application code. Originally targeted to optimize the memory footprint of reconstruction jobs, AthenaMP has demonstrated that it can reduce the memory usage of certain configurations of ATLAS production jobs by a factor of 2. AthenaMP has also evolved to become the parallel event-processing core of the recently developed ATLAS infrastructure for fine-grained event processing (Event Service) which allows the running of AthenaMP inside massively parallel distributed applications on hundreds of compute nodes simultaneously. We present the architecture of AthenaMP, various strategies implemented by AthenaMP for scheduling workload to worker processes (for example: Shared Event Queue and Shared Distributor of Event Tokens) and the usage of AthenaMP in the diversity of ATLAS event processing workloads on various computing resources: Grid, opportunistic resources and HPC.

Dual pathways to prospective remembering.

According to the multiprocess framework (McDaniel and Einstein, 2000), the cognitive system can support prospective memory (PM) retrieval through two general pathways. One pathway depends on top–down attentional control processes that maintain activation of the intention and/or monitor the environment for the triggering or target cues that indicate that the intention should be executed. A second pathway depends on (bottom–up) spontaneous retrieval processes, processes that are often triggered by a PM target cue; critically, spontaneous retrieval is assumed not to require monitoring or active maintenance of the intention. Given demand characteristics associated with experimental settings, however, participants are often inclined to monitor, thereby potentially masking discovery of bottom–up spontaneous retrieval processes. In this article, we discuss parameters of laboratory PM paradigms to discourage monitoring and review recent behavioral evidence from such paradigms that implicate spontaneous retrieval in PM. We then re-examine the neuro-imaging evidence from the lens of the multiprocess framework and suggest some critical modifications to existing neuro-cognitive interpretations of the neuro-imaging results. These modifications illuminate possible directions and refinements for further neuro-imaging investigations of PM.

Does predictability matter? Effects of cue predictability on neurocognitive mechanisms underlying prospective memory.

Prospective memory (PM) represents the ability to successfully realize intentions when the appropriate moment or cue occurs. In this study, we used event-related potentials (ERPs) to explore the impact of cue predictability on the cognitive and neural mechanisms supporting PM. Participants performed an ongoing task and, simultaneously, had to remember to execute a pre-specified action when they encountered the PM cues. The occurrence of the PM cues was predictable (being signaled by a warning cue) for some participants and was completely unpredictable for others. In the predictable cue condition, the behavioral and ERP correlates of strategic monitoring were observed mainly in the ongoing trials wherein the PM cue was expected. In the unpredictable cue condition they were instead shown throughout the whole PM block. This pattern of results suggests that, in the predictable cue condition, participants engaged monitoring only when subjected to a context wherein the PM cue was expected, and disengaged monitoring when the PM cue was not expected. Conversely, participants in the unpredictable cue condition distributed their resources for strategic monitoring in more continuous manner. The findings of this study support the most recent views—the “Dynamic Multiprocess Framework” and the “Attention to Delayed Intention” (AtoDI) model—confirming that strategic monitoring is a flexible mechanism that is recruited mainly when a PM cue is expected and that may interact with bottom-up spontaneous processes.

The Effect of Retention Interval Task Difficulty on Young Children's Prospective Memory: Testing the Intention Monitoring Hypothesis

The current study examined the impact of retention interval task difficulty on 4- and 5-year-olds’ prospective memory (PM) to test the hypothesis that children periodically monitor their intentions during the retention interval and that disrupting this monitoring may result in poorer PM performance. In addition, relations among PM, working memory, theory of mind (ToM), and 2 types of planning were investigated. Children (N = 64) were randomly assigned to an easy or difficult filler task during the retention interval prior to the PM task. Five-year-olds outperformed 4-year-olds on the PM task, and children receiving the easy filler task outperformed those receiving the difficult filler task. Further, working memory, planning, and ToM were positively associated with PM for children receiving the difficult filler task but not for children receiving the easy filler task. Findings are interpreted with respect to the predictions of the intention monitoring hypothesis as well as the multiprocess framework of PM.

Functional correlates of prospective memory in stroke

IntroductionProspective memory is the ability to remember actions to be performed later in time or when a certain event occurs. Multiple cognitive processes are involved in prospective memory, and the degree to which automatic or effortful processes are involved may differ for different types of prospective memory tasks. This study aimed to investigate prospective memory (dys)functioning in stroke patients, and to get more insight in which cognitive processes are involved in time- versus event-based prospective memory. MethodsWe investigated 39 community-dwelling stroke survivors and 53 matched control participants. Assessment included naturalistic and experimental event- and time-based prospective memory tasks, as well as standard neuropsychological measures of (retrospective) memory, processing speed and attention/executive functioning. Results41% of the stroke patients performed significantly worse than control participants on prospective memory tasks. Deficits in prospective memory occurred as frequently as impairments in retrospective memory (33%, χ2(1, N=39)=3.4, p=.066), and more often than impairments in attention/executive functioning (15%, χ2(1, N=39)=5.2, p=.022) and speed of processing (23%, χ2(1, N=39)=6.5, p=.011).Regression analyses showed that event-based (‘focal’) prospective memory is supported by retrospective memory, indicating that it is a relatively simple and automatic process. Time-based (non-‘focal’) prospective memory proved to be a more complex process, requiring active monitoring of the environment. Performance was predicted by speed of processing, attention/executive functioning and retrospective memory. Thirteen percent of the patients suffered from selective prospective memory impairment, which was associated with damage to the superior temporal gyrus. ConclusionsImpairment of prospective memory occurs frequently after stroke. Different cognitive operations are involved in distinct types of prospective memory. Results fit within the multi-process framework of prospective memory and help further specify its contents.

Coupled impacts of sea-level rise and tidal marsh restoration on endangered California clapper rail

We develop a predictive multi-process framework to quantitatively assess the spatially variable, interlinked dynamics of sea-level rise, wetland transition, habitat suitability and connectivity, and shorebird distribution and abundance. Bird behavior is represented in a spatially explicit agent-based model that tracks responses of individuals to predicted changes in local habitat quantity and quality. We apply this framework to the endangered California clapper rail (Rallus longirostris obsoletus) in the San Francisco Estuary, US, under a range of sea-level rise and conservation scenarios aimed at clapper rail recovery. The framework enables quantification of the relationship between critical habitat destruction and clapper rail population decline. The most influential factors that characterize the quality of tidal marsh habitat are salinity, which is a proxy for higher quality nesting environment and abundance of macroinvertebrates, and tidal conditions, which affect flood and predation threats. Results suggest that clapper rail viability should remain at the present level for moderate sea level rise. However, for a rise of 1.66m, extinction risk increases from 0.01 to 0.36. The framework enables quantitative evaluation of proposed conservation efforts, and should complement existing theory and empirical inferences. Compared with sub-regional efforts, estuary-wide conservation is more effective in improving reproduction and dispersal success and accommodates a sea-level rise of an additional ∼10cm before population falls below criticality. Should sea level rise to the predicted maximum, proposed conservation efforts are likely to be ineffective in preventing California clapper rail extinction by 2100.

The impact of age, ongoing task difficulty, and cue salience on preschoolers’ prospective memory performance: The role of executive function

The current study examined the impact of age, ongoing task (OT) difficulty, and cue salience on 4- and 5-year-old children’s prospective memory (PM) and also explored the relation between individual differences in executive function (working memory, inhibition, and shifting) and PM. OT difficulty and cue salience are predicted to affect the detection of PM cues based on the multiprocess framework, yet neither has been thoroughly investigated in young children. OT difficulty was manipulated by requiring children to sort cards according to the size of pictured items (easy) or by opposite size (difficult), and cue salience was manipulated by placing a red border around half of the target cues (salient) and no border around the other cues (non-salient). The 5-year-olds outperformed the 4-year-olds on the PM task, and salient PM cues resulted in better PM cues compared with non-salient cues. There was no main effect of OT difficulty, and the interaction between cue salience and OT difficulty was not significant. However, a planned comparison revealed that the combination of non-salient cues and a difficult OT resulted in significantly worse PM performance than that in all of the other conditions. Inhibition accounted for significant variance in PM performance for non-salient cues and for marginally significant variance for salient cues. Furthermore, individual differences in inhibition fully mediated the effect of age on PM performance. Results are discussed in the context of the multiprocess framework and with reference to preschoolers’ difficulty with the executive demands of dividing attention between the OT and PM task.