316 research outputs found

    A direct comparison of attentional orienting to spatial and temporal positions in visual working memory

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    Different visual attributes effectively guide attention to specific items in visual working memory (VWM), ensuring that particularly important memory contents are readily available. Predictable temporal structures contribute to this efficient use of VWM: items are prospectively prioritized when they are expected to be needed. Occasionally, however, visual events only gain relevance through their timing after they have passed. We investigated retrospective attentional orienting based on temporal position by directly comparing it with orienting to spatial locations, which is typically considered the most powerful selection mechanism. In a colour-change-detection task, in which items appeared sequentially at different locations, symbolic number cues validly indicated the temporal or spatial location of the upcoming probe item either before encoding (precues; Experiment 1) or during maintenance (retrocues; Experiments 1–3). Temporal and spatial cues were physically identical and only differed in their mapping onto either temporal or spatial positions. Predictive cues yielded cueing benefits (i.e., higher accuracy and shorter reaction times) as compared with neutral cues, with larger benefits for precues than for retrocues. Importantly, spatial and temporal cueing benefits did not differ. Equivalent retrocueing benefits were also observed across different cue-probe intervals and irrespective of whether spatial or temporal position was used as retrieval cue, indicating that items were directly bound to temporal position and not prioritized via a space-based mechanism. These findings show that spatial and temporal properties can be used equally well to flexibly prioritise representations held in VWM and they highlight the functional similarities of space and time in VWM.Peer Reviewe

    Microsaccade-induced prolongation of saccade latencies depends on microsaccade amplitude

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    Fixations consist of small movements including microsaccades, i.e., rapid flicks in eye position that replace the retinal image by up to 1 degree of visual angle. Recently, we showed in a delayed-saccade task (1) that the rate of microsaccades decreased in the course of saccade preparation and (2) that microsaccades occurring around the time of a go signal were associated with prolonged saccade latencies (Rolfs et al., 2006). A re-analysis of the same data set revealed a strong dependence of these findings on microsaccade amplitude. First, microsaccade amplitude dropped to a minimum just before the generation of a saccade. Second, the delay of response saccades was a function of microsaccade amplitude: Microsaccades with larger amplitudes were followed by longer response latencies. These finding were predicted by a recently proposed model that attributes microsaccade generation to fixation-related activity in a saccadic motor map that is in competition with the generation of large saccades (Rolfs et al., 2008). We propose, therefore, that microsaccade statistics provide a behavioral correlate of fixation-related activity in the oculomotor system

    ScanDy: Simulating Realistic Human Scanpaths in Dynamic Real-World Scenes

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    Memory for action: a functional view of selection in visual working memory

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    Perception is shaped by actions, which determine the allocation of selective attention across the visual field. Here, we review evidence that maintenance in visual working memory is similarly influenced by actions (eye or hand movements), planned and executed well after encoding: Representations that are relevant for an upcoming action – because they spatially correspond to the action goal or because they are defined along action-related feature dimensions – are automatically prioritised over action-irrelevant representations and held in a stable state. We summarise what is known about specific characteristics and mechanisms of selection-for-action in working memory, such as its temporal dynamics and spatial specificity, and delineate open questions. This newly-burgeoning area of research promotes a more functional perspective on visual working memory that emphasizes its role in action control.Peer Reviewe

    A comparison of the temporal and spatial properties of trans-saccadic perceptual recalibration and saccadic adaptation

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    Repeated exposure to a consistent trans-saccadic step in the position of the saccadic target reliably produces a change of saccadic gain, a well-established trans-saccadic motor learning phenomenon known as saccadic adaptation. Trans-saccadic changes can also produce perceptual effects. Specifically, a systematic increase or decrease in the size of the object that is being foveated changes the perceptually equivalent size between fovea and periphery. Previous studies have shown that this recalibration of perceived size can be established within a few dozen trials, persists overnight, and generalizes across hemifields. In the current study, we use a novel adjustment paradigm to characterize both temporally and spatially the learning process that subtends this form of recalibration, and directly compare its properties to those of saccadic adaptation. We observed that sinusoidal oscillations in the amplitude of the trans-saccadic change produce sinusoidal oscillations in the reported peripheral size, with a lag of under 10 trials. This is qualitatively similar to what has been observed in the case of saccadic adaptation. We also tested whether learning is generalized to the mirror location on the opposite hemifield for both size recalibration and saccade adaptation. Here the results were markedly different, showing almost complete generalization for recalibration and no generalization for saccadic adaptation. We conclude that perceptual and visuomotor consequences of trans-saccadic changes rely on learning mechanisms that are distinct but develop on similar time scales

    Razgraničenje neizravne namjere i svjesnog nehaja

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    U radu se obrađuje razgraničenje neizravne namjere i svjesnog nehaja, koje već generacijama predstavlja jedno od najznačajnijih spornih pitanja kaznenopravne znanosti. U prvom dijelu rada analiziraju se konceptualne razlike u shvaćanju pojma krivnje te se izlažu temeljne odrednice različitih učenja o namjeri i nehaju. Slijedi kritički prikaz važnijih teorija razgraničenja u njemačkoj i austrijskoj kaznenopravnoj dogmatici, koji je upotpunjen izlaganjem pojedinih kontroverznih slučajeva iz njemačke sudske prakse. Završni dio rada bavi se razgraničenjem u hrvatskom pravu de lege lata, pri čemu se izlaže model tumačenja kojim se u postojeće pozitivnopravne okvire nastoje inkorporirati suvremeni teorijski dosezi. Primjenjivost predloženog modela potom se ispituje na recentnom predmetu iz domaće sudske prakse

    Забезпечення розвитку інноваційності промислових підприємств при активізації інтелектуального капіталу суспільства

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    Проаналізовано стан і умови інноваційної діяльності підприємств в Україні. Досліджено проблеми неефективності державної політики в економічній сфері щодо розвитку інноваційності промислових підприємств. Розроблено пропозиції з удосконалення структури і напрямів діяльності державної політики щодо розвитку інноваційності промислових підприємств при активізації інтелектуального капіталу суспільства.Проанализированы состояние и условия инновационной деятельности предприятий в Украине. Исследованы проблемы неэффективности государственной политики в экономической сфере относительно развития инновационности промышленных предприятий. Разработаны предложения по усовершенствованию структуры и направлений деятельности государственной политики относительно развития инновационности промышленных предприятий при активизации интеллектуального капитала.The state and terms of innovative activity of enterprises in Ukraine are analyzed. Problems of inefficiency of public policy are investigated in an economic sphere in relation to innovativeness development of industrial enterprises. Suggestions for the improvement of structure and directions public policy activity in relation to innovativeness development of the industrial enterprises during activation of the society intellectual capital are worked out

    Clinically relevant depressive symptoms in young stroke patients - results of the sifap1 study

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    BACKGROUND Although post-stroke depression is widely recognized, less is known about depressive symptoms in the acute stage of stroke and especially in young stroke patients. We thus investigated depressive symptoms and their determinants in such a cohort. METHODS The Stroke in Young Fabry Patients study (sifap1) prospectively recruited a large multinational European cohort (n = 5,023) of patients with a cerebrovascular event aged 18-55. For assessing clinically relevant depressive symptoms (CRDS, defined by a BDI-score ≥18) the self-reporting Beck Depression Inventory (BDI) was obtained on inclusion in the study. Associations with baseline parameters, stroke severity (National Institutes of Health Stroke Scale, NIHSS), and brain MRI findings were analyzed. RESULTS From the 2007 patients with BDI documentation, 202 (10.1%) had CRDS. CRDS were observed more frequently in women (12.6 vs. 8.2% in men, p < 0.001). Patients with CRDS more often had arterial hypertension, diabetes mellitus, and hyperlipidemia than patients without CRDS (hypertension: 58.0 vs. 47.1%, p = 0.017; diabetes mellitus: 17.9 vs. 8.9%, p < 0.001; hyperlipidemia: 40.5 vs. 32.3%, p = 0.012). In the subgroup of patients with ischemic stroke or TIA (n = 1,832) no significant associations between CRDS and cerebral MRI findings such as the presence of acute infarcts (68.1 vs. 65.8%, p = 0.666), old infarctions (63.4 vs. 62.1%, p = 0.725) or white matter hyper-intensities (51.6 vs. 53.7%, p = 0.520) were found. CONCLUSION Depressive symptoms were present in 10.1% of young stroke patients in the acute phase, and were related to risk factors but not to imaging findings
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