Unrelated Processing Research Articles

The locus of the emotional Stroop effect: A study with the PRP paradigm

Stimuli that are clearly positive or negative (hence valence-laden stimuli) have the potential to interrupt unrelated task processing. A typical example is the emotional Stroop effect (ESE) in which responding to a certain task feature (e.g., color) is delayed by the presentation of task-irrelevant valent stimuli (e.g., negative pictures) compared to valence-neutral stimuli. Here we scrutinize which processes are slowed down by irrelevant but valent stimulation. In Experiment 1, participants performed in a Psychological Refractory Period (PRP) experiment with tone discrimination as Task 1 and color discrimination as Task 2. Importantly, colors in Task 2 were accompanied by valent or neutral pictures. Valent pictures delayed responding in Task 2 (thus an ESE) and this delay was additive to the time interval between tasks. In Experiment 2, task order was reversed and the ESE in Task 1 fully propagated to the Task 2 tone discrimination. These results imply that irrelevant valence-laden stimulation delays capacity-limited processes, and we suggest that this is a late perceptual process acting on stimulus categorization.

Effects of Relevance and Congruity on Survival Advantage of Memory

Lots of research found that survival processing led to superior retention of the words relative to other semantic encoding tasks, which was termed survival advantage of memory. Nairne and Pandeirada (2011) claimed that survival processing may be a special and powerful memory encoding procedure; but Butler, Kang, Roediger (2009) argued that Congruity effects between materials and processing tasks in the survival processing paradigm are critical cause of survival advantage of memory. In the present study, 2 experiments were conducted to investigate: 1) whether congruity will contribute to survival advantage of memory, namely whether people remember items better if those items are congruent with a survival scenario; 2) whether relevance of words to survival was the other cause of survival advantage of memory, namely whether higher relevance of words to survival will result in more superior memory performance. We preselected 45 words related to survival (15 high-related, 15 mid- related and 15 low-related words to survival scenario) and 24 words related to robbery (8 high-related, 8 mid-related, 8 low-related words to robbery scenario) by asking 80 participants to rate the words according to their relevance to survival scenario or to robbery scenario respectively. In experiment 1, 96 participants were asked to study 45 words in survival processing, pleasantness rating, and intentional memory procedures respectively, the results showed a significant survival advantage exists. In experiment 2a, we manipulated congruence between words and processing condition. 60 participants were asked to study 24 words related to robbery (preselected according to their relevance to robbery scenario) and 24 words related to survival (selected from experiment 1) in survival processing and robbery processing respectively; in experiment 2b, the other 60 participants were asked to study the same words as in experiment 2a under 2 unrelated processing conditions, such as pleasantness rating and intentional memory procedures respectively. The results of 2 experiments showed that: 1) congruence between words and processing condition enhanced memory performance, but not explained the whole survival advantage of memory; 2) high relevance to survival scenario of words per se did not result in survival advantage of memory, which may be affected by words frequency of study items preselected according to their relevance to survival, it deserves more further investigation. In a word, our results suggest survival advantage of memory is caused by survival processing, namely survival processing may be a special and powerful memory encoding procedure, which is consistent with the explanation of Nairne and Pandeirada (2011).

Scheduling unrelated parallel batch processing machines with non-identical job sizes

Scheduling unrelated parallel batch processing machines to minimize makespan is studied in this paper. Jobs with non-identical sizes are scheduled on batch processing machines that can process several jobs as a batch as long as the machine capacity is not violated. Several heuristics based on best fit longest processing time (BFLPT) in two groups are proposed to solve the problem. A lower bound is also proved to evaluate the quality of the heuristics. Computational experiments were undertaken. These showed that J_SC-BFLPT, considering both load balance of machines and job processing times, was robust and outperformed other heuristics for most of the problem categories.

Assessing new approaches to schedule a batch of identical intree-shaped workflows on a heterogeneous platform

In this paper, we consider the makespan optimisation when scheduling a batch of identical workflows on a heterogeneous platform as a service-oriented grid or a micro-factory. A job is represented by a directed acyclic graph (DAG) with typed tasks and no fork nodes (in-tree precedence constraints). The processing resources are able to process a set of task types, each with unrelated processing cost. The objective function is to minimise the execution makespan of a batch of identical workflows while most of the works concentrate on the throughput in this case. Three algorithms are studied in this context: a classical list algorithm and two algorithms based on new approaches, a genetic algorithm and a steady-state algorithm. The contribution of this paper is both on the adaptation of these algorithms to the particular case of batches of identical workflows and on the performance analysis of these algorithms regarding the makespan. We show the benefits of their adaptation, and we show that the algorithm performance depends on the structure of the workflow, on the size of the batch and on the platform characteristics.

Performance-dependent inhibition of pain by an executive working memory task

It is widely assumed that distraction reduces pain. Similarly, it is assumed that pain distracts from concurrent, unrelated cognitive processing, reducing performance on difficult tasks. Taken together, these assumptions suggest pain processing and cognitive function engage an overlapping set of domain-general, capacity-limited mental resources. However, experimental tests of this proposal have yielded mixed results, leading to alternative proposals that challenge the common model of a bidirectional relationship between concurrent pain and task performance. We tested these contrasting positions using a novel concurrent pain and executive working memory paradigm. Both task difficulty and nociceptive stimulus intensity were individually calibrated for each participant. Participants reported less pain during the working memory task than a visually matched control condition. Conversely, increasing levels of heat incrementally reduced task performance. Path analyses showed that variations in pain completely mediated this effect, and that even within a given heat level, trial-by-trial fluctuations in pain predicted decrements in performance. In sum, these findings argue that overlapping cognitive resources play a role in both pain processing and executive working memory. Future studies could use this paradigm to understand more precisely which components of executive function or other cognitive resources contribute to the experience of pain.