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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We confirm previous evidence indicating that word length has a substantial effect on word recognition in the LVF but a much weaker effect in both the RVF and fovea. The nature of encoding in the LVF is not altered when the words are vertically displayed (Experiment 2), and the effect cannot therefore be entirely due to scanning artefact or acuity gradients in peripheral vision. We provide evidence that links the asymmetrical influence of word length directly to hemispheric specialization: left-handers, who as a group are much less consistently lateralized than right-handers are also less affected by word length in the LVF on the average (Experiment 3). This occurs because the asymmetry for certain left-handers is either very weak or, in some cases, is the complete reverse of the asymmetry observed in right-handers. Finally, we demonstrate that the length x field interaction is observed in lexical decisions (Experiment 4) which do not entail pronunciation of written words. There is some indication that concrete, high-imageable words produce a smaller effect of length in the LVF than abstract, low-imageable words, and we discuss this outcome in relation to the proposal that the right hemisphere can sometimes extract a lexical code from letter information. The concept of distinct modes of word recognition in the LVF and RVF clarifies a number of issues in laterality research, and suggests a new approach to evaluating group differences in half-field performance.
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PMID:Different modes of word recognition in the left and right visual fields. 334 18

Twenty undergraduate men participated in a short-term recognition memory experiment in which single words of four types, classified by high and low imagery value and high and low Thorndike-Lorge frequency, were each presented twice unilaterally to the right and left visual fields (RVF, LVF). Stimuli were projected either to the same or to the opposite visual field on successive presentations. Results showed that: (1) imagery value affected responses to initial presentations, but not to repetitions; and (2) the speed and accuracy of recognizing repetitions in the LVF were the same whether the stimuli had been presented initially to the LVF or the RVF, whereas speed and accuracy in the RVF were significantly poorer for words initially presented to the LVF than for words initially presented to the RVF. The latter findings are consistent with differential encoding or with asymmetrical storage of verbal information in the two hemispheres, but not with the hypothesis that the memory store for words is confined to the language-dominant hemisphere.
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PMID:Interhemispheric effects in short-term recognition memory for single words. 718 28

Investigations of the laterality of phonological working memory have not always yielded consistent results. The present experiment investigated working memory for letters and numbers in two memory load conditions. In the low load condition, working memory for letters and numbers was similar. However, in the high load condition, males were more accurate at the recall of letters. This effect was not observed with numbers, in which both sexes performed more poorly. Furthermore, we observed consistent RVF advantages for both tasks, although males were more asymmetrical for the recall of letters and females were more asymmetrical for the recall of numbers. This result indicates that laterality of working memory for letters and numbers differs, and these asymmetries depend upon the sex of the participant.
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PMID:Laterality of phonological working memory: dependence on type of stimulus, memory load, and sex. 1203 May 1

In our previous event-related potential (ERP) study [A. Nowicka, I. Szatkowska, Memory-induced modulation of event-related potentials in frontal cortex of human subjects: a divided visual field study, Neurosci. Lett. 359 (2004) 171-174], word repetition effects in right-handed males were observed only in case of the direct stimulation of the left (competent) hemisphere. Since the left-handedness and the factor of female gender may determine the lateralization of verbal functions, the goal of the present study was to test the sensitivity of the ERP repetition effects to the visual field of word presentation in the group of left- and right-handed women. ERPs were recorded from symmetrical sites over the left and right hemisphere. Target words were presented in the left (LVF) or right (RVF) visual hemifield. Subjects' were instructed to recognize the target word on a response card. A substantial portion of words was repeated twice. Words elicited different ERPs at frontal sites when presented the first and second times: ERPs were more positive to the repeated stimulus than to its first occurrence. However, in right-handed participants, repetition effects were only observed when target words were presented to the RVF whereas in left-handed participants, repetition effects were only observed when target words were presented to the LVF. These findings are indicative of the asymmetrical involvement of the two hemispheres in memory-induced modulation of brain activity related to verbal processing in left- and right-handed women.
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PMID:Lateralization of repetition effects in event-related potentials to words in left- and right-handed women. 1622 46

The well-established right visual field (RVF-lh) advantage in word recognition is commonly attributed to the typical left hemisphere dominance in language; words presented to the LVF-rh are processed less efficiently due to the need for transcallosal transfer from the right to left hemisphere. The exact stage for this hemispheric transfer is currently unsettled. Some studies suggest that transfer occurs at very early stages between primary visual regions, whereas other studies suggest that transfer occurs between the left visual word form area and its right hemisphere homolog. This study explores these conflicting accounts and finds evidence for both. Participants conducted a lateralized lexical decision task with both unilateral and bilateral display conditions. Connectivity analyses were conducted from magnetoencephalography signals that were localized to the left middle occipital gyrus (LMOG), right middle occipital gyrus (RMOG), left visual word form area (LVWFA), and right visual word form area (RVWA). Results from unilateral trials showed asymmetrical interhemispheric connectivity from the RMOG to LMOG and symmetrical interhemispheric connectivity between the LVWFA and RVWFA. Furthermore, bilateral presentations led to reduced interhemispheric connectivity between both homologous region of interest pairs. Together, these results suggest that lateralized word recognition involves multiple stages of interhemispheric interactions and that these interactions are reduced with bilateral displays.
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PMID:Interhemispheric connectivity during lateralized lexical decision. 3037 29