340 research outputs found

    Tachistoscopic presentation of verbal stimuli for assessing cerebral dominance: Reliability data and some practical recommendations.

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    Reliability data point to rather high test-retest correlations (>.65) for VHF data with four- and live-letter words as stimuli, but replicate previous findings that the first test score correlates poorly with later test scores. The same results are obtained for accuracy and latency data, though small differences exist. All laterality indices lead to the same conclusions and have high intercorrelations. The point-biserial correlation coefficient is, however, a slightly more reliable index of naming latency than the mere difference between LVF and RVF. No such superiority is found for the indices based on accuracy data. The results also point to the need to present a sufficient number of stimuli before firm conclusions can be drawn

    Individual analysis of laterality data

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    Graphical and statistical analyses are presented that allow one to check for an individual subject whether the performance during a session is stable. whether the difference between the left and the right visual half-field is significant. and whether the performance is uniform over different sessions. Analyses are given for accuracy data and for latency data. Though the analyses are described for a visual half-field experiment, they can easily be adapted for other laterality tasks

    Age and interhemispheric transfer time: A failure to replicate.

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    In a recent study with the Poffenberger paradigm, Brizzolara et al. reported longer estimates of interhemispheric transfer time (IHTT) for children aged 7 years than for adults. They interpreted this finding as evidence for incomplete functional maturity of the corpus callosum in young children. The present study was we were unable to replicate the age effect reported by Brizzolara et al. A closer look at the original study revealed that only 80 observations per child had been collected, which makes it probable that the larger IHTTs in 7-year-olds were caused by stimulus-response compatibility rather than by the lower efficiency of the corpus callosum during childhood years

    Eye movement control during reading: foveal load and parafoveal processing.

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    We tested theories of eye movement control in reading by looking at parafoveal processing. According to attention-processing theories, attention shifts towards word n+ 1 only when processing of the fixated word n is finished, so that attended parafoveal processing does not start until the programming of the saccade programming to word n+ 1 is initiated (Henderson &amp; Ferreira, 1990; Morrison, 1984), or even later when the processing of word n takes too long (Henderson &amp; Ferreira, 1990). Parafoveal preview benefit should be constant whatever the foveal processing load (Morrison, 1984), or should decrease when processing word n outlasts an eye movement programming deadline (Henderson &amp; Ferreira, 1990). By manipulating the frequency and length of the foveal word n and the visibility of the parafoveal word n+ 1, we replicated the finding that the parafoveal preview benefit is smaller with a low-frequency word in foveal vision. Detailed analyses, however, showed that the eye movement programming deadline hypothesis could not account for this finding which was due not to cases where the low-frequency words n had received a long fixation, but to cases of a short fixations less than 240 msec. In addition, there was a spill-over effect of word n to word n+ 1, and there was an element of parallel processing of both words. The results are more in line with parallel processing limited by the extent to which the parafoveal word processing on fixation n can be combined with the foveal word processing on fixation n+ 1. </jats:p

    Norms of age of acquisition and concreteness for 30,000 Dutch words

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    Abstract not availableMarc Brysbaert, Michaël Stevens, Simon De Deyne, Wouter Voorspoels, Gert Storm

    Towards a unified understanding of lateralized vision:A large-scale study investigating principles governing patterns of lateralization using a heterogeneous sample

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    While functional lateralization of the human brain has been a widely studied topic in the past decades, few studies to date have gone further than investigating lateralization of single, isolated processes. With the present study, we aimed to arrive at a more unified view by investigating lateralization patterns in face and word processing, and associated lower-level visual processing. We tested a large and heterogeneous participant group, and used a number of tasks that had been shown to produce replicable indices of lateralized processing of visual information of different types and complexity. Following Bayesian statistics, group-level analyses showed the expected right hemisphere (RH) lateralization for face, global form, low spatial frequency processing, and spatial attention, and left hemisphere (LH) lateralization for visual word and local feature processing. Compared to right-handed individuals, lateralization patterns of left-handed and especially those who are RH-dominant for language deviated from this 'typical' pattern. Our results support the notion that face and word processes come to be lateralized to homologue areas of the two hemispheres, under influence of the RHand LH-specializations in global form, local feature, and low and high spatial frequency processing. As such, we present a more unified understanding of lateralized vision, providing evidence for the input asymmetry and causal complementarity principles of lateralized visual information processing. The absence of correlations between spatial attention and lateralization of the other processes supports the notion of their independent lateralization, conform the statistical complementarity principle. (C) 2020 The Author(s). Published by Elsevier Ltd

    Structural Invariants in Individuals Language Use: The "Ego Network" of Words

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    The cognitive constraints that humans exhibit in their social interactions have been extensively studied by anthropologists, who have highlighted their regularities across different types of social networks. We postulate that similar regularities can be found in other cognitive processes, such as those involving language production. In order to provide preliminary evidence for this claim, we analyse a dataset containing tweets of a heterogeneous group of Twitter users (regular users and professional writers). Leveraging a methodology similar to the one used to uncover the well-established social cognitive constraints, we find that a concentric layered structure (which we call ego network of words, in analogy to the ego network of social relationships) very well captures how individuals organise the words they use. The size of the layers in this structure regularly grows (approximately 2–3 times with respect to the previous one) when moving outwards, and the two penultimate external layers consistently account for approximately 60% and 30% of the used words (the outermost layer contains 100% of the words), irrespective of the number of the total number of layers of the user
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