203 research outputs found

    The unfolding action model of initiation times, movement times, and movement paths

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    Converging evidence has led to a consensus in favor of computational models of behavior implementing continuous information flow and parallel processing between cognitive processing stages. Yet, such models still typically implement a discrete step between the last cognitive stage and motor implementation. This discrete step is implemented as a fixed decision bound that activation in the last cognitive stage needs to cross before action can be initiated. Such an implementation is questionable as it cannot account for two important features of behavior. First, it does not allow to select an action while withholding it until the moment is appropriate for executing it. Second, it cannot account for recent evidence that cognition is not confined prior to movement initiation, but consistently leaks into movement. To address these two features, we propose a novel neurocomputational model of cognitionaction interactions, namely the unfolding action model (UAM). Crucially, the model implements adaptive information flow between the last cognitive processing stage and motor implementation. We show that the UAM addresses the two abovementioned features. Empirically, the UAM accounts for traditional response time data, including positively skewed initiation time distribution, functionally fixed decision bounds and speed-accuracy trade-offs in button-press experimental designs. Moreover, it accounts for movement times, movement paths, and how they are influenced by cognitive-experimental manipulations. This move should close the current gap between abstract decision-making models and behavior observed in natural habitats.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

    Non-spatial neglect for the mental number line

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    Several psychophysical investigations, expanding the classical introspective observations by Galton, have suggested that the mental representation of numbers takes the form of a number line along which magnitude is positioned in ascending order according to reading habits, i.e. from left to right in Western cultures. In keeping with the evidence, pathological rightward deviations in the bisection of number intervals due to right brain damage are generally interpreted as originating from a purely spatial-attentional deficit in the processing of the left side of number intervals. However, consistent double dissociations between defective processing of the left side of physical and mental number space have called into question the universality of this interpretation. Recent evidence suggests a link between rightward deviations in number space and defective memory for both spatial and non-spatial sequences of items. Here we describe the case of a left brain-damaged patient exhibiting right-sided neglect for extrapersonal and representational space, and left-sided neglect on the mental number line. Accurate neuropsychological examination revealed that the apparent left-sided neglect in the bisection of number intervals had a purely non-spatial origin and was based on mnemonic difficulties for the initial items of verbal sequences presented visually at an identical spatial position. These findings show that effective position-based verbal working memory might be crucial for numerical tasks that are usually considered to involve purely spatial representation of numerical magnitudes. © 2011 Elsevier Ltd.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

    The role of subjective experiences in conflict tasks : a review

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    Cognitive control research is concerned with the question how we install adaptive behaviour in the case of (cognitive) conflict. In this review we focus on the role that awareness of this conflict plays in our ability to exert cognitive control. We will argue that visual conflict is not the only building block of metacognitive experiences of conflict and discuss how they are related to cognitive control. So, a first aim of the current review is to understand how these different metacognitive judgements are created. To do so, we draw some remarkable parallels with research on metacognition in decision making and memory research. Next, we elaborate on the relationship between metacognition and adaptive behaviour, with a specific focus on the role of subjective experiences in the Gratton effect. The grey areas that persist in the current literature are highlighted. In addition to deciphering the mechanisms of metacognitive judgements in cognitive control, this overview also aims to further enlarge our understanding of metacognitive abilities at a more general level

    Continuous track paths reveal additive evidence integration in multistep decision making

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    Increased orienting to unexpected action outcomes in schizophrenia

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    Although some recent research has indicated reduced performance monitoring in patients with schizophrenia, the literature on this topic shows some remarkable inconsistencies. While most studies suggest diminished error signals following error responses, some studies reported normal post-error slowing, while others reported reduced post-error slowing. Here we review these studies and highlight the most important discrepancies. Furthermore, we argue that overall error rates are a mostly neglected issue that can at least partly explain these discrepancies. It has been reported previously that post-error slowing depends on the error rates. Participants or patients that make more errors are likely to show decreased post-error slowing. Therefore, when a group of patients is compared to a group of controls, it is extremely important to match error rates. For this purpose, we developed a procedure where we matched individuals' error rates. In a task where subjects had to press a response key corresponding to one of four colors we manipulated the difficulty on an individual basis by varying the discriminability between the colors. Schizophrenic patients and a group of controls were tested with this procedure showing that differences in accuracy disappear. Interestingly, we can see that in patients, the color values that were needed to reach similar levels of accuracy correlate with the Positive and Negative Syndrome Scale (PANSS) scale, with higher PANSS requiring more color. Most important, we found that schizophrenic patients have increased rather than decreased post-error slowing when the inter-trial interval (ITI) is short. This result can be interpreted within the framework of the orienting account, as it has been demonstrated previously that schizophrenic patients show increased distractibility

    Metacognition and cognitive control : behavioural adaptation requires conflict experience

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    Cognitive control allows adapting our behaviour to improve performance. A behavioural signature of cognitive control is the Gratton effect. This effect is observed in conflict tasks and indicates smaller congruency effects after incongruent trials than after congruent trials. Metacognitive experience may play a role in this effect: When participants introspect on their conflict experience, the Gratton effect follows the conflict introspection instead of the stimulus congruency. However this Gratton effect could also be triggered by the labelling that the introspective method implies and/or by a misperception of the stimulus conflict. The current study investigated whether the experiential component of the introspection is necessary to trigger cognitive control or whether labelling a trial as conflicting or not can be sufficient. In a priming task, Gratton effects following metacognitive conflict experience and conflict label were contrasted. Replicating earlier reports, results showed that the metacognitive experience of conflict can trigger a Gratton effect. However a conflict label, either generated by the participants themselves or presented to the participants via feedback was not able to induce cognitive control. Results are discussed in light of current theories of cognitive control

    An investigation of sponsor attributes on six megaproject cases

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    PURPOSE : Executive sponsors play a significant role in the success of megaprojects which, in turn, affect national economies and millions of people. However, the literature on the requisite attributes of project sponsors on megaprojects is still sparse. The purpose of the paper is to provide guidelines to company boards and executives who are tasked to appoint suitable executive sponsors to megaprojects. Thus, the paper contributes to the sparse literature on megaproject sponsors. DESIGN/METHODOLOGY/APPROACH : A total of 26 senior managers, with experience in megaprojects ranging from 8 to 15 years – and who were involved in 6 recent megaprojects with a combined value of US$13.75bn – were interviewed on the attributes of megaproject sponsors. Transcriptions of semi-structured, open-ended interviews were analysed with computer-assisted qualitative data analysis software (CAQDAS). FINDINGS : The study identified the most essential attribute as appropriate seniority, being empowered and accountable, with appropriate seniority, being empowered and accountable, with apposite credibility and with both personal and positional power. The study also uncovered 13 attributes – all components of “competence” – which have not previously been explicitly identified in literature as elements of sponsor “competence”. ORIGINALITY/VALUE : In the current study guidelines are provided for the selection and appointment of appropriate megaproject sponsors.https://www.emerald.com/insight/publication/issn/1753-8378hj2022Graduate School of Technology Management (GSTM

    Losing the boundary: Cognition biases action well after action selection.

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    Ordinality: The importance of its trial list composition and examining its relation with adults’ arithmetic and mathematical reasoning

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    Understanding whether a sequence is presented in an order or not (i.e., ordinality) is a robust predictor of adults’ arithmetic performance, but the mechanisms underlying this skill and its relationship with mathematics remain unclear. In this study, we examined (a) the cognitive strategies involved in ordinality inferred from behavioural effects observed in different types of sequences and (b) whether ordinality is also related to mathematical reasoning besides arithmetic. In Experiment 1, participants performed an arithmetic, a mathematical reasoning test, and an order task, which had balanced trials on the basis of order, direction, regularity, and distance. We observed standard distance effects (DEs) for ordered and non-ordered sequences, which suggest reliance on magnitude comparison strategies. This contradicts past studies that reported reversed distance effects (RDEs) for some types of sequences, which suggest reliance on retrieval strategies. Also, we found that ordinality predicted arithmetic but not mathematical reasoning when controlling for fluid intelligence. In Experiment 2, we investigated whether the aforementioned absence of RDEs was because of our trial list composition. Participants performed two order tasks: in both tasks, no RDE was found demonstrating the fragility of the RDE. In addition, results showed that the strategies used when processing ordinality were modulated by the trial list composition and presentation order of the tasks. Altogether, these findings reveal that ordinality is strongly related to arithmetic and that the strategies used when processing ordinality are highly dependent on the context in which the task is presented
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