Differences in Multitask Resource Reallocation After Change in Task Values

International audienceObjective The objective was to characterize multitask resource reallocation strategies when managing subtasks with various assigned values.Background When solving a resource conflict in multitasking, Salvucci and Taatgen predict a globally rational strategy will be followed that favors the most urgent subtask and optimizes global performance. However, Katidioti and Taatgen identified a locally rational strategy that optimizes only a subcomponent of the whole task, leading to detrimental consequences on global performance. Moreover, the question remains open whether expertise would have an impact on the choice of the strategy.Method We adopted a multitask environment used for pilot selection with a change in emphasis on two out of four subtasks while all subtasks had to be maintained over a minimum performance. A laboratory eye-tracking study contrasted 20 recently selected pilot students considered as experienced with this task and 15 university students considered as novices.Results When two subtasks were emphasized, novices focused their resources particularly on one high-value subtask and failed to prevent both low-value subtasks falling below minimum performance. On the contrary, experienced people delayed the processing of one low-value subtask but managed to optimize global performance.Conclusion In a multitasking environment where some subtasks are emphasized, novices follow a locally rational strategy whereas experienced participants follow a globally rational strategy.Application During complex training, trainees are only able to adjust their resource allocation strategy to subtask emphasis changes once they are familiar with the multitasking environment

Human-plant interaction at the onset of agriculture: the PATH project

Plant domestication represents a major turning point in human history, resulting in the shift from a hunting/gathering/fishing-based economy to food production. Combining the analysis of ground stone tools and dental calculus, the PATH project aims to investigate dynamics of plant consumption, and the knowledge and toolkits involved in their processing

The use of ash at Late Lower Paleolithic Qesem Cave, Israel—An integrated study of use-wear and residue analysis

Employing an integrated approach to investigate the use of Late Lower Paleolithic flint tools found at the site of Qesem Cave (Israel), we revealed a particular trace pattern related to the employment of ashes at the site. Using a designated collection of replica items and combining use-wear and residue (morphological analysis, FTIR, SEM-EDX) analyses, we revealed the intentional use of ashes in preserving foods for delayed consumption as well as hide for delayed processing. Our interpretation, we believe is the most plausible one since we were able to delineate the specific use-wear fingerprints of the intentional use of ashes for such purposes, suggesting that our approach might be useful for the recognition of other similar functional-behavioral patterns. Lastly, in support of previous findings at Qesem Cave, our current findings present evidence for the processing of organic matters intentionally mixed with ash, leading us to suggest that the inhabitants of Qesem Cave were proficient not only in the habitual use of fire but also of its main by-product, ash. Hence, we call for a reassessment of the timeline currently assigned to hominins’ utilization of ash for storing and processing vegetal foods and hide

The Chickpea, Summer Cropping, and a New Model for Pulse Domestication in the Ancient Near East

The widely accepted models describing the emergence of domesticated grain crops from their wild type ancestors are mostly based upon selection (conscious or unconscious) of major features related either to seed dispersal (nonbrittle ear, indehiscent pod) or free germination (nondormant seeds, soft seed coat). Based on the breeding systems (self-pollination) and dominance relations between the allelomorphs of seed dispersal mode and seed dormancy, it was postulated that establishment of the domesticated forms and replacement of the wild ancestral populations occurred in the Near East within a relatively short time. Chickpea (Cicer arietinum L.), however, appears as an exception among all other “founder crops” of Old World agriculture because of its ancient conversion into a summer crop. The chickpea is also exceptional because its major domestication trait appears to be vernalization insensitivity rather than pod indehiscence or free germination. Moreover, the genetic basis of vernalization response in wild chickpea (Cicer reticulatum Ladiz.) is polygenic, suggesting that a long domestication process was imperative due to the elusive phenotype of vernalization nonresponsiveness. There is also a gap in chickpea remains in the archaeological record between the Late Prepottery Neolithic and the Early Bronze Age. Contrary to the common view that Levantine summer cropping was introduced relatively late (Early Bronze Age), we argue for an earlier (Neolithic) Levantine origin of summer cropping because chickpea, when grown as a common winter crop, was vulnerable to the devastating pathogen Didymella rabiei, the causal agent of Ascochyta blight. The ancient (Neolithic) conversion of chickpea into a summer crop required seasonal differentiation of agronomic operation from the early phases of the Neolithic revolution. This topic is difficult to deal with, as direct data on seasonality in prehistoric Old World field crop husbandry are practically nonexistent. Consequently, this issue was hardly dealt with in the literature. Information on the seasonality of ancient (Neolithic, Chalcolithic, and Early Bronze Age, calibrated 11,500 to 4,500 years before present) Near Eastern agriculture may improve our understanding of the proficiency of early farmers. This in turn may provide a better insight into Neolithic agrotechniques and scheduling. It is difficult to fully understand chickpea domestication without a Neolithic seasonal differentiation of agronomic practice because the rapid establishment of the successful Near Eastern crop package which included wheats, barley, pea, lentil, vetches, and flax, would have preempted the later domestication of this rare wild legume

Striatal Volume Predicts Level of Video Game Skill Acquisition

Video game skills transfer to other tasks, but individual differences in performance and in learning and transfer rates make it difficult to identify the source of transfer benefits. We asked whether variability in initial acquisition and of improvement in performance on a demanding video game, the Space Fortress game, could be predicted by variations in the pretraining volume of either of 2 key brain regions implicated in learning and memory: the striatum, implicated in procedural learning and cognitive flexibility, and the hippocampus, implicated in declarative memory. We found that hippocampal volumes did not predict learning improvement but that striatal volumes did. Moreover, for the striatum, the volumes of the dorsal striatum predicted improvement in performance but the volumes of the ventral striatum did not. Both ventral and dorsal striatal volumes predicted early acquisition rates. Furthermore, this early-stage correlation between striatal volumes and learning held regardless of the cognitive flexibility demands of the game versions, whereas the predictive power of the dorsal striatal volumes held selectively for performance improvements in a game version emphasizing cognitive flexibility. These findings suggest a neuroanatomical basis for the superiority of training strategies that promote cognitive flexibility and transfer to untrained tasks.United States. Office of Naval Research (grant number N00014-07-1-0903

Simulation Training in U.K. General Aviation: An Undervalued Aid to Reducing Loss of Control Accidents

Analysis of data from 1,007 U.K. general aviation (GA) accidents demonstrates the predominant cause of accidents is loss of control, exacerbated by a lack of recent flying experience. These are long-standing problems that can be targeted effectively with simulation training. Discussion on training strategies in commercial aviation reinforces the logic of introducing simulation training for the GA pilot. Conclusions drawn affirm the notion that GA safety would benefit from implementation of regulated simulation training

Neural network analysis for predicting metrics of fragmented laminar artifacts: a case study from MPPNB sites in the Southern Levant

This study was aimed at introducing a new method for predicting the original metrics of fragmented standardized artifacts, specifically of flint blades from the Middle Pre-Pottery Neolithic B (10,200/100–9,500/400 cal B.P.) in the Southern Levant. The excessive re-use of these artifacts or poor preservation conditions often prevent a complete set of metric data from being obtained. Our suggested approach is based on readily accessible machine learning (artificial intelligence) and neural network analysis. These are performed in a multi-paradigm programming language and numeric computing environment, with parameters represented by a rapid measurement system based on the technological features shared by all lithic artifacts of the studied assemblages. This method can be applied to various chronologies and/or contexts. A full set of metric data, including potential typological and functional elements of the assemblages studied, may provide a better understanding of the lithic technology involved; highlight cultural aspects related to the chaîne opératoire of the studied lithic production; and address issues related to cultural sub-divisions in larger-scale applications. Herein, neural network analysis was performed on blade samples from Middle Pre-Pottery Neolithic B sites from the Southern Levant specifically Nahal Yarmuth 38, Motza, Yiftahel, and Nahal Reuel

Watching People Making Decisions: A Gogglebox on Online Consumer Interaction

This paper presents a research study, using eye tracking technology, to measure participant cognitive load when encountering micro-decision. It elaborates and improves on a pilot study that was used to test the experiment design. Prior research that led to a taxonomy of decision constructs faced in online transactional processes is discussed. The main findings relate to participants’ subjective cognitive load and task error rates