Overcoming the effect of letter confusability in letter-by-letter reading: A rehabilitation study

Parafoveal letter identification in Russian: Confusion matrices based on error rates

In the present study, we introduce parafoveal letter confusion matrices for the Russian language, which uses the Cyrillic script. To ensure that our confusion rates reflect parafoveal processing and no other effects, we employed an adapted boundary paradigm (Rayner, 1975) that prevented the participants from directly fixating the letter stimuli. Additionally, we assessed confusability under isolated and word-like (crowded) conditions using two modern fonts, since previous research showed that letter recognition depended on crowding and font (Coates, 2015; Pelli et al., 2006). Our additional goal was to gain insight into what letter features or configurational patterns might be essential for letter recognition in Russian; thus, we conducted exploratory clustering analysis on visual confusion scores to identify groups of similar letters. To support this analysis, we conducted a comprehensive review of over 20 studies that proposed crucial properties of Latin letters relevant to character perception. The summary of this review is valuable not only for our current study but also for future research in the field.

The role of variation in phonological and semantic working memory capacities in sentence comprehension: neural evidence from healthy and brain-damaged individuals

Research on the role of working memory (WM) in language processing has typically focused on WM for phonological information. However, considerable behavioral evidence supports the existence of a separate semantic WM system that plays a greater role in language processing. We review the neural evidence that supports the distinction between phonological and semantic WM capacities and discuss how individual differences in these capacities relate to sentence processing. In terms of neural substrates, findings from multivariate functional MRI for healthy participants and voxel-based lesion-symptom mapping for brain-damaged participants imply that the left supramarginal gyrus supports phonological WM, whereas the left inferior frontal gyrus (LIFG) and angular gyrus support semantic WM. In sentence comprehension, individual variation in semantic but not phonological WM related to performance in resolving semantic information and the LIFG region implicated in semantic WM showed fMRI activation during the resolution of semantic interference. Moreover, variation for brain-damaged participants in the integrity of a fiber tract supporting semantic WM had a greater relation to the processing of complex sentences than did the integrity of fiber tracts supporting phonological WM. Overall, the neural findings provide converging evidence regarding the distinction of these two capacities and the greater contribution of individual differences in semantic than phonological WM capacity to sentence processing.

The Use of a Reading Lexicon to Aid Contextual Vocabulary Acquisition by EFL Arab Learners

This article investigates how the use of a deliberate approach of analyzing a given reading may predict differences in CVA effectiveness. Sixty Arab EFL learners were randomly assigned to an experimental group and a control group, thirty participants for each. The experimental group received training in the deliberate Clarke and Nation (System 8:211-220, 1980) CVA technique, whereas the control group were not guided through a training method. Then, both groups were asked to answer three vocabulary tests and then participate to finish a series of six readings adjusted using Nation's K-level reading lexicon to control the difficult words during readings. After treatments, the students took a post-test vocabulary session. Results show that the group that have used the deliberate CVA technique retained about twice as many new words as the other group did. That is the use of a deliberate-CVA methodology significantly improves learning. The experimental manipulation produced a learning effect that was 76.1% greater than that of the control group in terms of word context recognition and 128.0% greater than that of the control group in terms of word definition accuracy. Pedagogical implications, limitations and directions for further research are discussed.

Temporal grouping modulates ipsilateral capture in right visual neglect

The current study assessed the performance of a patient with right neglect (M.A.H.) across various manipulations of the flanker paradigm. When required to identify a central target in the presence of a unilateral flanker, M.A.H. responded to the flanking distractor on the left (ipsilesional) side as if it were the target, even when the flanker appeared at left peripheral locations. A right (contralesional) flanker did not affect central identification performance (Experiment 1). The "ipsilesional capture" effect persisted when pretrial location markers were introduced to make the flanker and target locations more clearly defined (Experiment 2). However, when the ipsilesional flanker appeared simultaneously with a contralesional flanker, central target detection improved to ceiling (Experiment 3). Interestingly, with these three-stimulus displays, congruency effects in reaction time only occurred in relation to the flanker on the contralesional side (Experiment 3), suggesting impaired response selectivity to ipsilesional stimuli. Congruency effects were produced on both sides only when the two flanking distractors grouped together (by both onset and offset, Experiment 4) and when the ipsilesional flanking distractor grouped with the target by onset (lone contra offset, Experiment 4). The results are attributed to ipsilesional capture in central target detection, which is offset by temporal grouping processes when another stimulus appears on the contralateral side.

What lies beneath: a comparison of reading aloud in pure alexia and semantic dementia

Exaggerated effects of word length upon reading-aloud performance define pure alexia, but have also been observed in semantic dementia. Some researchers have proposed a reading-specific account, whereby performance in these two disorders reflects the same cause: impaired orthographic processing. In contrast, according to the primary systems view of acquired reading disorders, pure alexia results from a basic visual processing deficit, whereas degraded semantic knowledge undermines reading performance in semantic dementia. To explore the source of reading deficits in these two disorders, we compared the reading performance of 10 pure alexic and 10 semantic dementia patients, matched in terms of overall severity of reading deficit. The results revealed comparable frequency effects on reading accuracy, but weaker effects of regularity in pure alexia than in semantic dementia. Analysis of error types revealed a higher rate of letter-based errors and a lower rate of regularization responses in pure alexia than in semantic dementia. Error responses were most often words in pure alexia but most often nonwords in semantic dementia. Although all patients made some letter substitution errors, these were characterized by visual similarity in pure alexia and phonological similarity in semantic dementia. Overall, the data indicate that the reading deficits in pure alexia and semantic dementia arise from impairments of visual processing and knowledge of word meaning, respectively. The locus and mechanisms of these impairments are placed within the context of current connectionist models of reading.