858 resultados para Cognitive Processes


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To determine whether the visuospatial n-back working memory task is a reliable and valid measure of cognitive processes believed to underlie intelligence, this study compared the reaction times and accuracy of perforniance of 70 participants, with performance on the Multidimensional Aptitude Battery (MAB). Testing was conducted over two sessions separated by 1 week. Participants completed the MAB during the second test session. Moderate testretest reliability for percentage accuracy scores was found across the four levels of the n-back task, whilst reaction times were highly reliable. Furthermore, participants' performance on the MAB was negatively correlated with accuracy of performance at the easier levels of the n-back task and positively correlated with accuracy of performance at the harder task levels. These findings confirm previous research examining the cognitive basis of intelligence, and suggest that intelligence is the product of faster speed of information processing, as well as superior working memory capacity. (C) 2004 Elsevier Inc. All rights reserved.

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There is ongoing debate whether the efficiency of local cognitive processes leads to global cognitive ability or whether global ability feeds the efficiency of basic processes. A prominent example is the well-replicated association between inspection time (IT), a measure of perceptual discrimination speed, and intelligence (IQ), where it is not known whether increased speed is a cause or consequence of high IQ. We investigated the direction of causation between IT and IQ in 2012 genetically related subjects from Australia and The Netherlands. Models in which the reliable variance of each observed variable was specified as a latent trait showed IT correlations of -0.44 and -0.33 with respective Performance and Verbal IQ; heritabilities were 57% (IT), 83% (PIQ) and 77% (VIQ). Directional causation models provided poor fits to the data, with covariation best explained by pleiotropic genes (influencing variation in both IT and IQ). This finding of a common genetic factor provides a better target for identifying genes involved in cognition than genes which are unique to specific traits.

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Two studies in the context of English-French relations in Québec suggest that individuals who strongly identify with a group derive the individual-level costs and benefits that drive expectancy-value processes (rational decision-making) from group-level costs and benefits. In Study 1, high identifiers linked group- and individual-level outcomes of conflict choices whereas low identifiers did not. Group-level expectancy-value processes, in Study 2, mediated the relationship between social identity and perceptions that collective action benefits the individual actor and between social identity and intentions to act. These findings suggest the rational underpinnings of identity-driven political behavior, a relationship sometimes obscured in intergroup theory that focuses on cognitive processes of self-stereotyping. But the results also challenge the view that individuals' cost-benefit analyses are independent of identity processes. The findings suggest the importance of modeling the relationship of group and individual levels of expectancy-value processes as both hierarchical and contingent on social identity processes

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An assumption of theory-based physical activity interventions is that active participation positively affects the theoretical constructs upon which the intervention is based. This assumption is rarely tested. This study assessed whether participation, defined as completion of homework, in a lifestyle physical activity intervention was associated with changes over 6 months in constructs the homework addressed: the behavioral and cognitive processes of change, self-efficacy, and decisional balance (the pros and cons). Participants were 244 sedentary adults aged 25 to 75 years. They completed an average of 12 of 20 homework assignments. Those completing at least two-thirds of the homework (n = 113) had greater changes in the theoretical constructs from pretest to posttest than those completing less (n = 90). Post-hoc analyses suggest that completing theory-based homework may impact the processes of change and self-efficacy in lifestyle physical activity interventions and, therefore, are warranted in future interventions.

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Experiments with simulators allow psychologists to better understand the causes of human errors and build models of cognitive processes to be used in human reliability assessment (HRA). This paper investigates an approach to task failure analysis based on patterns of behaviour, by contrast to more traditional event-based approaches. It considers, as a case study, a formal model of an air traffic control (ATC) system which incorporates controller behaviour. The cognitive model is formalised in the CSP process algebra. Patterns of behaviour are expressed as temporal logic properties. Then a model-checking technique is used to verify whether the decomposition of the operator's behaviour into patterns is sound and complete with respect to the cognitive model. The decomposition is shown to be incomplete and a new behavioural pattern is identified, which appears to have been overlooked in the analysis of the data provided by the experiments with the simulator. This illustrates how formal analysis of operator models can yield fresh insights into how failures may arise in interactive systems.

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Esta pesquisa investiga a influência de intervenções lúdicas na diminuição da ansiedade materna com mães de recém-nascidos pré-termo hospitalizados, em um hospital universitário da Grande São Paulo. São estudadas 30 mães que tiveram parto prematuro, com faixa etária entre 16 e 40 anos e escolaridade até 2º grau, por meio de estudo avaliativo-interventivo-evolutivo. Inicia-se por uma entrevista psicológica semidirigida, com o objetivo de traçar o histórico gestacional, seguida de aplicação da Escala de Ansiedade, Depressão e Irritabilidade IDA, visando identificar o nível de ansiedade materna e do Inventário de Percepção Neonatal IPN-I para verificar a expectativa das mães em relação ao comportamento de choro, alimento e vômito de seus bebês pré-termo. A seguir são efetuadas intervenções grupais lúdicas em 16 encontros, um a cada semana, de 60 minutos, segundo modelo piagetiano, que estimula processos afetivosemocionais e cognitivos. Os dados relativos ao histórico gestacional revelam que 75% das mães encontram-se na segunda gestação e já sofreram aborto ou óbito fetal; têm ida de gestacional média de 31 semanas; peso médio do bebê ao nascer de 1.640g. e tempo de internação médio de 39,93 dias. Na análise do IDA em relação à ansiedade, 75% delas apresentam escore de alta intensidade (11,25), também alto quanto à depressão (10); o escore médio (3,73) da irritabilidade exteriorizada acompanha o da irritabilidade interiorizada (3,23). A correlação entre depressão e ansiedade indica que uma reação emocional segue a outra, não havendo diferença significativa importante entre ambas (p=0,306). O IPN-I comprova que as 30 mães têm expectativas em relação ao próprio filho similares aos bebês em geral, mostrando escores médios de 8,63 e 9,20, respectivamente, confirmados pelo escore 10,0 apontado em 75% da amostra, o que configura uma alta expectativa quanto aos aspectos de sono, alimentação e vômito dos bebês. A análise qualitativa revela que a criação de grupos lúdicos mostra-se favorável, com alta adesão e motivação das mães, favorecendo a diminuição da ansiedade, a adaptação à realidade vivida e a interação mãe-bebê de forma saudável durante a internação. O estudo apresenta a trajetória interventiva de três casos emblemáticos de diferentes níveis de ansiedade, ilustrando esta evolução. Estes dados sugerem que esta modalidade de intervenção caracterize-se como uma medida de prevenção, promoção e preservação da saúde física e psíquica da mãe e do recémnascido prematuro, com repercussões na família e na sociedade.(AU)

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Signal integration determines cell fate on the cellular level, affects cognitive processes and affective responses on the behavioural level, and is likely to be involved in psychoneurobiological processes underlying mood disorders. Interactions between stimuli may subjected to time effects. Time-dependencies of interactions between stimuli typically lead to complex cell responses and complex responses on the behavioural level. We show that both three-factor models and time series models can be used to uncover such time-dependencies. However, we argue that for short longitudinal data the three factor modelling approach is more suitable. In order to illustrate both approaches, we re-analysed previously published short longitudinal data sets. We found that in human embryonic kidney 293 cells cells the interaction effect in the regulation of extracellular signal-regulated kinase (ERK) 1 signalling activation by insulin and epidermal growth factor is subjected to a time effect and dramatically decays at peak values of ERK activation. In contrast, we found that the interaction effect induced by hypoxia and tumour necrosis factor-alpha for the transcriptional activity of the human cyclo-oxygenase-2 promoter in HEK293 cells is time invariant at least in the first 12-h time window after stimulation. Furthermore, we applied the three-factor model to previously reported animal studies. In these studies, memory storage was found to be subjected to an interaction effect of the beta-adrenoceptor agonist clenbuterol and certain antagonists acting on the alpha-1-adrenoceptor / glucocorticoid-receptor system. Our model-based analysis suggests that only if the antagonist drug is administer in a critical time window, then the interaction effect is relevant.

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Recent functional magnetic resonance imaging (fMRI) investigations of the interaction between cognition and reward processing have found that the lateral prefrontal cortex (PFC) areas are preferentially activated to both increasing cognitive demand and reward level. Conversely, ventromedial PFC (VMPFC) areas show decreased activation to the same conditions, indicating a possible reciprocal relationship between cognitive and emotional processing regions. We report an fMRI study of a rewarded working memory task, in which we further explore how the relationship between reward and cognitive processing is mediated. We not only assess the integrity of reciprocal neural connections between the lateral PFC and VMPFC brain regions in different experimental contexts but also test whether additional cortical and subcortical regions influence this relationship. Psychophysiological interaction analyses were used as a measure of functional connectivity in order to characterize the influence of both cognitive and motivational variables on connectivity between the lateral PFC and the VMPFC. Psychophysiological interactions revealed negative functional connectivity between the lateral PFC and the VMPFC in the context of high memory load, and high memory load in tandem with a highly motivating context, but not in the context of reward alone. Physiophysiological interactions further indicated that the dorsal anterior cingulate and the caudate nucleus modulate this pathway. These findings provide evidence for a dynamic interplay between lateral PFC and VMPFC regions and are consistent with an emotional gating role for the VMPFC during cognitively demanding tasks. Our findings also support neuropsychological theories of mood disorders, which have long emphasized a dysfunctional relationship between emotion/motivational and cognitive processes in depression.

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We discuss the application of beamforming techniques to the field of magnetoencephalography (MEG). We argue that beamformers have given us an insight into the dynamics of oscillatory changes across the cortex not explored previously with traditional analysis techniques that rely on averaged evoked responses. We review several experiments that have used beamformers, with special emphasis on those in which the results have been compared to those observed in functional magnetic resonance imaging (fMRI) and on those studying induced phenomena. We suggest that the success of the beamformer technique, despite the assumption that there are no linear interactions between the mesoscopic local field potentials across distinct cortical areas, may tell us something of the balance between functional integration and segregation in the human brain. What is more, MEG beamformer analysis facilitates the study of these complex interactions within cortical networks that are involved in both sensory-motor and cognitive processes. © 2005 Wiley-Liss, Inc.

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Category-specific disorders are frequently explained by suggesting that living and non-living things are processed in separate subsystems (e.g. Caramazza & Shelton, 1998). If subsystems exist, there should be benefits for normal processing, beyond the influence of structural similarity. However, no previous study has separated the relative influences of similarity and semantic category. We created novel examples of living and non-living things so category and similarity could be manipulated independently. Pre-tests ensured that our images evoked appropriate semantic information and were matched for familiarity. Participants were trained to associate names with the images and then performed a name-verification task under two levels of time pressure. We found no significant advantage for living things alongside strong effects of similarity. Our results suggest that similarity rather than category is the key determinant of speed and accuracy in normal semantic processing. We discuss the implications of this finding for neuropsychological studies. © 2005 Psychology Press Ltd.

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This article uncovers the complexities and contradictions inherent in making decisions about L1 use in the English language classroom. Through an analysis of data from classrooms in a Cypriot context and from interviews with Cypriot teachers, a number of functions for L1 use are identified, as are the teachers' rationales for using L1 for different functions. Teachers' decision making, it emerges, is often complex, based on either what they perceive as their students' affective needs or on their cognitive processes.What ismore, teachers often under-report or differently report their use of L1 in the classroom, contradicting beliefs by their actions. The construct of guilt is offered to explain these complexities and contradictions in the teachers' use of L1 in this study. We conclude by suggesting that teachers should be supported in finding local solutions to local teaching problems, so that they better understand and exploit the resources available to them. © The Author 2010. Published by Oxford University Press; all rights reserved.

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Collaborative working with the aid of computers is increasing rapidly due to the widespread use of computer networks, geographic mobility of people, and small powerful personal computers. For the past ten years research has been conducted into this use of computing technology from a wide variety of perspectives and for a wide range of uses. This thesis adds to that previous work by examining the area of collaborative writing amongst groups of people. The research brings together a number of disciplines, namely sociology for examining group dynamics, psychology for understanding individual writing and learning processes, and computer science for database, networking, and programming theory. The project initially looks at groups and how they form, communicate, and work together, progressing on to look at writing and the cognitive processes it entails for both composition and retrieval. The thesis then details a set of issues which need to be addressed in a collaborative writing system. These issues are then followed by developing a model for collaborative writing, detailing an iterative process of co-ordination, writing and annotation, consolidation, and negotiation, based on a structured but extensible document model. Implementation issues for a collaborative application are then described, along with various methods of overcoming them. Finally the design and implementation of a collaborative writing system, named Collaborwriter, is described in detail, which concludes with some preliminary results from initial user trials and testing.

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Despite abundant literature on human behaviour in the face of danger, much remains to be discovered. Some descriptive models of behaviour in the face of danger are reviewed in order to identify areas where documentation is lacking. It is argued that little is known about recognition and assessment of danger and yet, these are important aspects of cognitive processes. Speculative arguments about hazard assessment are reviewed and tested against the results of previous studies. Once hypotheses are formulated, the reason for retaining the reportory grid as the main research instrument are outlined, and the choice of data analysis techniques is described. Whilst all samples used repertory grids, the rating scales were different between samples; therefore, an analysis is performed of the way in which rating scales were used in the various samples and of some reasons why the scales were used differently. Then, individual grids are looked into and compared between respondents within each sample; consensus grids are also discussed. the major results from all samples are then contrasted and compared. It was hypothesized that hazard assessment would encompass three main dimensions, i.e. 'controllability', 'severity of consequences' and 'likelihood of occurrence', which would emerge in that order. the results suggest that these dimensions are but facets of two broader dimensions labelled 'scope of human intervention' and 'dangerousness'. It seems that these two dimensions encompass a number of more specific dimensions some of which can be further fragmented. Thus, hazard assessment appears to be a more complex process about which much remains to be discovered. Some of the ways in which further discovery might proceed are discussed.

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Although event-related potentials (ERPs) are widely used to study sensory, perceptual and cognitive processes, it remains unknown whether they are phase-locked signals superimposed upon the ongoing electroencephalogram (EEG) or result from phase-alignment of the EEG. Previous attempts to discriminate between these hypotheses have been unsuccessful but here a new test is presented based on the prediction that ERPs generated by phase-alignment will be associated with event-related changes in frequency whereas evoked-ERPs will not. Using empirical mode decomposition (EMD), which allows measurement of narrow-band changes in the EEG without predefining frequency bands, evidence was found for transient frequency slowing in recognition memory ERPs but not in simulated data derived from the evoked model. Furthermore, the timing of phase-alignment was frequency dependent with the earliest alignment occurring at high frequencies. Based on these findings, the Firefly model was developed, which proposes that both evoked and induced power changes derive from frequency-dependent phase-alignment of the ongoing EEG. Simulated data derived from the Firefly model provided a close match with empirical data and the model was able to account for i) the shape and timing of ERPs at different scalp sites, ii) the event-related desynchronization in alpha and synchronization in theta, and iii) changes in the power density spectrum from the pre-stimulus baseline to the post-stimulus period. The Firefly Model, therefore, provides not only a unifying account of event-related changes in the EEG but also a possible mechanism for cross-frequency information processing.

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Purpose – This paper aims to explore the antecedents of careerist orientations to work. Hypotheses are drawn from referent cognitions theory. First, it is proposed that trust mediates the relationship between an individual's perceptions of procedural justice and their careerist orientations to work. Second, perceptions of distributive justice, regarding the allocation of career development opportunities, will moderate the relationship between trust and careerist orientations to work. Design/methodology/approach – A total of 325 employees of a large UK financial institution completed a structured questionnaire. Regression analysis (using SPSS version 11) was used to test the presented hypotheses. Findings – All hypotheses were confirmed. However, the interaction effect observed was different from that hypothesised. It appears that trust only matters, in terms of the development of careerist orientations to work, when individuals feel that they are receiving equitable career development opportunities. Research limitations/implications – Much more research is required in different organisational contexts if one is to fully confirm and understand these relationships. However, these findings suggest that employers will only reduce the development of careerist attitudes in their workforce if they ensure the fair distribution of career development opportunities and engender trusting relations through the implementation of fair decision-making procedures. Originality/value – This paper adds much needed empirical research to the literature on new career realities and careerist orientations to work. Moreover, referent cognitions theory is presented as a new theoretical framework for understanding the cognitive processes involved in an individual's development of careerist attitudes.