Chaitra Rao

'Cost in transliteration': the neurocognitive processing of Romanized writing.

Romanized transliteration is widely used in internet communication and global commerce, yet we know little about its behavioural and neural processing. Here, we show that Romanized text imposes a significant neurocognitive load. Readers faced greater difficulty in identifying concrete words written in Romanized transliteration (Romanagari) compared to L1 and L2. Functional neuroimaging revealed that the neural cost of processing transliterations arose from significantly greater recruitment of language (left precentral gyrus, left inferior parietal lobule) and attention networks (left mid-cingulum). Additionally, transliterated text uniquely activated attention and control areas compared to both L1 (cerebellar vermis) and L2 (pre-supplementary motor area/pre-SMA). We attribute the neural effort of reading Romanized transliteration to (i) effortful phonological retrieval from unfamiliar orthographic forms and (ii) conflicting attentional demands imposed by mapping orthographic forms of one language to phonological-semantic representations in another. Finally, significant brain-behaviour correlation suggests that the left mid-cingulum modulates cognitive-linguistic conflict.

Reading in Devanagari: Insights from functional neuroimaging

Objectives: The current study used functional MRI (fMRI) to obtain a comprehensive understanding of the neural network underlying visual word recognition in Hindi/Devanagari, an alphasyllabic – partly alphabetic and partly syllabic Indian writing system on which little research has hitherto been carried out. Materials and Methods: Sixteen (5F, 11M) neurologically healthy, native Hindi/Devanagari readers aged 21 to 50 named aloud 240 Devanagari words which were either visually linear – had no diacritics or consonant ligatures above or below central plane of text, e.g. फल, वाहन, or nonlinear – had at least one diacritic and/or ligature, e.g. फूल, किरण, and which further included 120 words each of high and low frequency. Words were presented in alternating high and low frequency blocks of 10 words each at 2s/word in a block design, with linear and nonlinear words in separate runs. Word reading accuracy was manually coded, while fMRI images were acquired on a 3T scanner with an 8-channel head-coil, using a T2*-weighted EPI sequence (TR/TE = 2s/35ms). Results: After ensuring high word naming accuracy (M = 97.6%, SD = 2.3), fMRI data analyses (at FDR P < 0.005) revealed that reading Devanagari words elicited robust activations in bilateral occipito-temporal, inferior frontal and precentral regions as well as both cerebellar hemispheres. Other common areas of activation included left inferior parietal and right superior temporal cortices. Primary differences seen between nonlinear and linear word reading networks were in the right temporal areas and cerebellum. Conclusion: Distinct from alphabetic scripts, which are linear in their spatial organization, and recruit a primarily left-lateralized network for word reading, our results revealed a bilateral reading network for Devanagari. We attribute the additional activations in Devanagari to increased visual processing demands arising from the complex visuospatial arrangement of symbols in this ancient script.

A role for putamen in phonological processing in children

Bilingual children are required to successfully develop phonological skills in two languages, yet little is known about the neural correlates associated with them. We obtained structural imaging data from 30 Hindi–English children aged between 8 and 10 years and used voxel based morphometry to explore neuroanatomical correlates of behavioural measures of phonological awareness. Our results showed that phonological skills in English are predicted by grey matter volume of bilateral putamen, but solely by right putamen in Hindi. Post-hoc analysis revealed that English nonword reading correlates with grey matter volume in bilateral putamen while in Hindi nonword reading it correlates only with right putamen. These differences in putamen-based mechanisms indicate that syllable level awareness sufficiently supports early literacy in the transparent, alphasyllabic Hindi orthography whereas that in English requires both phonemic and syllabic level awareness. Our findings point towards a key role for putamen in mediating phonological and reading skills in children.

The case of the neglected alphasyllabary: Orthographic processing in Devanagari

We applaud Ram Frost for highlighting the need for multicultural perspectives while developing universal models of visual word recognition. We second Frosts proposal that factors like lexical morphology should be incorporated besides purely orthographic features in modeling word recognition. In support, we provide fresh evidence from Hindi (written in Devanagari), an example of hitherto under-represented alphasyllabic orthographies, in which flexible encoding of aksara (character) position is constrained by the morphological structure of words.

Morphology, orthography, and the two hemispheres: A divided visual field study with Hindi/Urdu biliterates

&NA; Although identical on the spoken level, Hindi and Urdu differ markedly on the written level in terms of reading/writing direction and orthographic depth, with discernible processing consequences. The present study used a divided field paradigm to study the impact of writing system characteristics of Hindi and Urdu on word naming latencies in skilled biliterate users of these languages. Hindi (read/written from left to right) was hypothesized to show a larger right field advantage than Urdu (read/written from right to left); Hindi words sharing form overlap with primes were expected to show a significant priming effect in the left visual field, but a significant right field effect for morphologically‐primed naming. Both these expectations were confirmed. An overall right field advantage was obtained for one syllable Hindi and Urdu words; two syllable Urdu words showed either no visual field differences or a left field advantage, and the right field advantage for Hindi was significantly greater for two syllable than one syllable words. Further, Hindi words showed significant form priming (relative to control stimuli) in the left visual field and significant morphological priming (relative to form priming) in the right visual field. By contrast, Urdu words showed no significant form priming in either visual field, and significantly greater morphological than form priming in the left visual field. These results are taken to suggest that visual field asymmetries in word naming are sensitive to differences in reading habit‐related scanning biases and to orthographic depth‐related differences in word recognition processes. HighlightsHindi words were named faster than Urdu and only Hindi showed form priming.Urdu two syllable words showed a left field naming advantage.Morphological priming was greater in Urdu than Hindi.Hindi form priming showed a left field advantage.Urdu morphological priming showed a left field advantage.