The contribution of phonological knowledge, memory, and language background to reading comprehension in deaf populations

Resolving syntactic-semantic conflicts: comprehension and processing patterns by deaf Chinese readers

The current study combined sentence plausibility judgment and self-paced reading tasks to examine the comprehension strategies and processing patterns of Chinese deaf individuals when comprehending written Chinese sentences with syntactic-semantic cue conflicts. Similar to findings from previous crosslinguistic studies on deaf readers, the Chinese deaf readers showed great variability in their comprehension strategies, with only 38% robustly relying on syntactic cues. Regardless of their overall comprehension preferences, the deaf readers all showed additional processing efforts as reflected by longer reading time at the verb regions when they relied on the syntactic cues. Those with less robust reliance on syntactic cues also showed longer reading time at the verb regions even when they relied on the semantic cues, suggesting sensitivity to the syntactic cues regardless of the comprehension strategy. These findings suggest that deaf readers in general endure more processing burden while resolving conflicting syntactic and semantic cues, likely due to their overall high reliance on semantic information during sentence comprehension. Increased processing burden thus may contribute to an overall tendency of over-reliance on semantic cues when comprehending sentences with cue conflicts.

Sensitivity to orthographic vs. phonological constraints on word recognition: An ERP study with deaf and hearing readers

The role of phonology in word recognition has previously been investigated using a masked lexical decision task and transposed letter (TL) nonwords that were either pronounceable (barve) or unpronounceable (brvae). We used event-related potentials (ERPs) to investigate these effects in skilled deaf readers, who may be more sensitive to orthotactic than phonotactic constraints, which are conflated in English. Twenty deaf and twenty hearing adults completed a masked lexical decision task while ERPs were recorded. The groups were matched in reading skill and IQ, but deaf readers had poorer phonological ability. Deaf readers were faster and more accurate at rejecting TL nonwords than hearing readers. Neither group exhibited an effect of nonword pronounceability in RTs or accuracy. For both groups, the N250 and N400 components were modulated by lexicality (more negative for nonwords). The N250 was not modulated by nonword pronounceability, but pronounceable nonwords elicited a larger amplitude N400 than unpronounceable nonwords. Because pronounceable nonwords are more word-like, they may incite activation that is unresolved when no lexical entry is found, leading to a larger N400 amplitude. Similar N400 pronounceability effects for deaf and hearing readers, despite differences in phonological sensitivity, suggest these TL effects arise from sensitivity to lexical-level orthotactic constraints. Deaf readers may have an advantage in processing TL nonwords because of enhanced early visual attention and/or tight orthographic-to-semantic connections, bypassing the phonologically mediated route to word recognition.

Electrophysiological patterns of visual word recognition in deaf and hearing readers: An ERP mega-study

Deaf and hearing readers have different access to spoken phonology which may affect the representation and recognition of written words. We used ERPs to investigate how a matched sample of deaf and hearing adults (total n = 90) responded to lexical characteristics of 480 English words in a go/no-go lexical decision task. Results from mixed effect regression models showed a) visual complexity produced small effects in opposing directions for deaf and hearing readers, b) similar frequency effects, but shifted earlier for deaf readers, c) more pronounced effects of orthographic neighborhood density for hearing readers, and d) more pronounced effects of concreteness for deaf readers. We suggest hearing readers have visual word representations that are more integrated with phonological representations, leading to larger lexically-mediated effects of neighborhood density. Conversely, deaf readers weight other sources of information more heavily, leading to larger semantically-mediated effects and altered responses to low-level visual variables.

Culture is not destiny, for reading: highlighting variable routes to literacy within writing systems

Cross-writing system research in psychology and cognitive neuroscience has yielded important findings regarding how a writing system's structure can influence the cognitive challenges of learning to read and the neural underpinnings of literacy. The current paper reviews these differences and extends the findings to demonstrate diversity in how skilled reading is accomplished within a single writing system, English. We argue that broad clusters of behavioral and neural patterns found across writing systems can also be found within subpopulations who display atypical routes to skilled English reading, subpopulations including Chinese-English bilinguals, deaf native signers, compensated readers, and distortion-sensitive readers. The patterns of interest include a tradeoff between the degree of reliance on phonological and morphological processing for skilled reading, a shift in attentional focus from smaller to larger orthographic units, and enhanced bilaterality of neural processing during word reading. Lastly, we consider how understanding atypical routes to reading may apply to other writing systems.

Predictors of Word and Text Reading Fluency of Deaf Children in Bilingual Deaf Education Programmes

Reading continues to be a challenging task for most deaf children. Bimodal bilingual education creates a supportive environment that stimulates deaf children’s learning through the use of sign language. However, it is still unclear how exposure to sign language might contribute to improving reading ability. Here, we investigate the relative contribution of several cognitive and linguistic variables to the development of word and text reading fluency in deaf children in bimodal bilingual education programmes. The participants of this study were 62 school-aged (8 to 10 years old at the start of the 3-year study) deaf children who took part in bilingual education (using Dutch and Sign Language of The Netherlands) and 40 age-matched hearing children. We assessed vocabulary knowledge in speech and sign, phonological awareness in speech and sign, receptive fingerspelling ability, and short-term memory at time 1 (T1). At times 2 (T2) and 3 (T3), we assessed word and text reading fluency. We found that (1) speech-based vocabulary strongly predicted word and text reading at T2 and T3, (2) fingerspelling ability was a strong predictor of word and text reading fluency at T2 and T3, (3) speech-based phonological awareness predicted word reading accuracy at T2 and T3 but did not predict text reading fluency, and (4) fingerspelling and STM predicted word reading latency at T2 while sign-based phonological awareness predicted this outcome measure at T3. These results suggest that fingerspelling may have an important function in facilitating the construction of orthographical/phonological representations of printed words for deaf children and strengthening word decoding and recognition abilities.

Simple View of Reading in Deaf and Hard-of-Hearing Adults

The present study investigated the relative contribution of the two components in the simple view of reading to the reading comprehension skills of deaf and hard-of-hearing (DHH) adults in the Netherlands. Eighty DHH adults, aged between 30 and 80 years old, were tested on word reading, reading fluency, vocabulary, and reading comprehension. Regression analyses showed that both decoding skills and vocabulary contributed to the reading comprehension skills of DHH adults, with vocabulary being the strongest predictor. For skilled decoders, the picture was somewhat different with only vocabulary being a predictor of reading comprehension. The results of this study show that the simple view of reading is applicable to DHH adults' reading comprehension skills: both decoding skills and vocabulary contribute to reading comprehension. Also, as in previous studies on the simple view of reading, as readers become more skilled in the decoding process, vocabulary becomes the only predictor of reading comprehension.

Manual and Spoken Cues in French Sign Language's Lexical Access: Evidence From Mouthing in a Sign-Picture Priming Paradigm

Although Sign Languages are gestural languages, the fact remains that some linguistic information can also be conveyed by spoken components as mouthing. Mouthing usually tend to reproduce the more relevant phonetic part of the equivalent spoken word matching with the manual sign. Therefore, one crucial issue in sign language is to understand whether mouthing is part of the signs themselves or not, and to which extent it contributes to the construction of signs meaning. Another question is to know whether mouthing patterns constitute a phonological or a semantic cue in the lexical sign entry. This study aimed to investigate the role of mouthing on the processing of lexical signs in French Sign Language (LSF), according the type of bilingualism (intramodal vs. bimodal). For this purpose, a behavioral sign-picture lexical decision experiment was designed. Intramodal signers (native deaf adults) and Bimodal signers (fluent hearing adults) have to decide as fast as possible whether a picture matched with the sign seen just before. Five experimental conditions in which the pair sign-mouthing were congruent or incongruent were created. Our results showed a strong interference effect when the sign-mouthing matching was incongruent, reflected by higher error rates and lengthened reaction times compared with the congruent condition. This finding suggests that both groups of signers use the available lexical information contained in mouthing during accessing the sign meaning. In addition, deaf intramodal signers were strongly interfered than hearing bimodal signers. Taken together, our data indicate that mouthing is a determining factor in LSF lexical access, specifically in deaf signers.

Masked ERP repetition priming in deaf and hearing readers

Deaf readers provide unique insights into how the reading circuit is modified by altered linguistic and sensory input. We investigated whether reading-matched deaf and hearing readers (n = 62) exhibit different ERP effects associated with orthographic to phonological mapping (N250) or lexico-semantic processes (N400). In a visual masked priming paradigm, participants performed a go/no-go categorization task; target words were preceded by repeated or unrelated primes. Prime duration and word frequency were manipulated. Hearing readers exhibited typical N250 and N400 priming effects with 50 ms primes (greater negativity for unrelated primes) and smaller effects with 100 ms primes. Deaf readers showed a surprising reversed priming effect with 50 ms primes (greater negativity for related primes), and more typical N250 and N400 effects with 100 ms primes. Correlation results suggested deaf readers with poorer phonological skills drove this effect. We suggest that weak phonological activation may create orthographic "repetition enhancement" or form/lexical competition in deaf readers.

The neurocognitive basis of skilled reading in prelingually and profoundly deaf adults

Deaf individuals have unique sensory and linguistic experiences that influence how they read and become skilled readers. This review presents our current understanding of the neurocognitive underpinnings of reading skill in deaf adults. Key behavioural and neuroimaging studies are integrated to build a profile of skilled adult deaf readers and to examine how changes in visual attention and reduced access to auditory input and phonology shape how they read both words and sentences. Crucially, the behaviours, processes, and neural circuity of deaf readers are compared to those of hearing readers with similar reading ability to help identify alternative pathways to reading success. Overall, sensitivity to orthographic and semantic information is comparable for skilled deaf and hearing readers, but deaf readers rely less on phonology and show greater engagement of the right hemisphere in visual word processing. During sentence reading, deaf readers process visual word forms more efficiently and may have a greater reliance on and altered connectivity to semantic information compared to their hearing peers. These findings highlight the plasticity of the reading system and point to alternative pathways to reading success.

Unmasking individual differences in adult reading procedures by disrupting holistic orthographic perception

Word identification is undeniably important for skilled reading and ultimately reading comprehension. Interestingly, both lexical and sublexical procedures can support word identification. Recent cross-linguistic comparisons have demonstrated that there are biases in orthographic coding (e.g., holistic vs. analytic) linked with differences in writing systems, such that holistic orthographic coding is correlated with lexical-level reading procedures and vice versa. The current study uses a measure of holistic visual processing used in the face processing literature, orientation sensitivity, to test individual differences in word identification within a native English population. Results revealed that greater orientation sensitivity (i.e., greater holistic processing) was associated with a reading profile that relies less on sublexical phonological measures and more on lexical-level characteristics within the skilled English readers. Parallels to Chinese procedures of reading and a proposed alternative route to skilled reading are discussed.

Spelling in Deaf, Hard of Hearing and Hearing Children With Sign Language Knowledge

What do spelling errors look like in children with sign language knowledge but with variation in hearing background, and what strategies do these children rely on when they learn how to spell in written language? Earlier research suggests that the spelling of children with hearing loss is different, because of their lack of hearing, which requires them to rely on other strategies. In this study, we examine whether, and how, different variables such as hearing degree, sign language knowledge and bilingualism may affect the spelling strategies of children with Swedish sign language, Svenskt teckenspråk, (STS) knowledge, and whether these variables can be mirrored in these children's spelling. The spelling process of nineteen children with STS knowledge (mean age: 10.9) with different hearing degrees, born into deaf families, is described and compared with a group of fourteen hearing children without STS knowledge (mean age: 10.9). Keystroke logging was used to investigate the participants' writing process. The spelling behavior of the children was further analyzed and categorized into different spelling error categories. The results indicate that many children showed exceptionally few spelling errors compared to earlier studies, that may derive from their early exposure of STS, enabling them to use the fingerspelling strategy. All of the children also demonstrated similar typing skills. The deaf children showed a tendency to rely on a visual strategy during spelling, which may result in incorrect, but visually similar, words, i.e., a type of spelling errors not found in texts by hearing children with STS knowledge. The deaf children also showed direct transfer from STS in their spelling. It was found that hard-of-hearing children together with hearing children of deaf adults (CODAs), both with STS knowledge, used a sounding strategy, rather than a visual strategy. Overall, this study suggests that the ability to hear and to use sign language, together and respectively, play a significant role for the spelling patterns and spelling strategies used by the children with and without hearing loss.

Modality and Interrelations Among Language, Reading, Spoken Phonological Awareness, and Fingerspelling

Better understanding of the mechanisms underlying early reading skills can lead to improved interventions. Hence, the purpose of this study was to examine multivariate associations among reading, language, spoken phonological awareness, and fingerspelling abilities for three groups of deaf and hard-of-hearing (DHH) beginning readers: those who were acquiring only spoken English (n = 101), those who were visual learners and acquiring sign (n = 131), and those who were acquiring both (n = 104). Children were enrolled in kindergarten, first, or second grade. Within-group and between-group confirmatory factor analysis showed that there were both similarities and differences in the abilities that underlie reading in these three groups. For all groups, reading abilities related to both language and the ability to manipulate the sublexical features of words. However, the groups differed on whether these constructs were based on visual or spoken language. Our results suggest that there are alternative means to learning to read. Whereas all DHH children learning to read rely on the same fundamental abilities of language and phonological processing, the modality, levels, and relations among these abilities differ.

ERP Evidence for Co-Activation of English Words during Recognition of American Sign Language Signs

Event-related potentials (ERPs) were used to investigate co-activation of English words during recognition of American Sign Language (ASL) signs. Deaf and hearing signers viewed pairs of ASL signs and judged their semantic relatedness. Half of the semantically unrelated signs had English translations that shared an orthographic and phonological rime (e.g., BAR-STAR) and half did not (e.g., NURSE-STAR). Classic N400 and behavioral semantic priming effects were observed in both groups. For hearing signers, targets in sign pairs with English rime translations elicited a smaller N400 compared to targets in pairs with unrelated English translations. In contrast, a reversed N400 effect was observed for deaf signers: target signs in English rime translation pairs elicited a larger N400 compared to targets in pairs with unrelated English translations. This reversed effect was overtaken by a later, more typical ERP priming effect for deaf signers who were aware of the manipulation. These findings provide evidence that implicit language co-activation in bimodal bilinguals is bidirectional. However, the distinct pattern of effects in deaf and hearing signers suggests that it may be modulated by differences in language proficiency and dominance as well as by asymmetric reliance on orthographic versus phonological representations.

The Role of Short Vowels in Arabic Listening Comprehension

The goal of the present study was to investigate the effect of short Arabic vowels on listening comprehension. It is well documented that short vowels affect reading and reading comprehension in Arabic literacy. Since reading comprehension and listening comprehension share many commonalities, it is assumed that short vowels will positively affect listening comprehension too. Two listening conditions were presented to students in three grade levels, 7th, 10th and 12th grades: a fully vowelized text and the second without short vowels (on ends of words). Students had to listen and answer multiple choice comprehension questions about the read aloud texts. Further, interviews were conducted with 10 volunteered students from each grade level to get their feedback about their experience. The results indicated significant differences between the two listening conditions in favor of the fully vowelized condition. The results are discussed in relation to different orthographies, reading comprehension, phonology, working memory and comprehension.

ERP effects of masked orthographic neighbour priming in deaf readers

In masked priming studies with hearing readers, neighbouring words (e.g., wine, vine) compete through lateral inhibition. Here, we asked whether lateral inhibition also characterizes visual word recognition in deaf readers and whether the neural signature of this competition is the same as for hearing readers. Only real words have lexical representations that engage in lateral inhibition. Therefore, we compared processing of target words following neighbouring prime words (e.g., wine-VINE) and pseudowords (e.g., bine-VINE). Targets following words elicited larger amplitude N400s and slower lexical decision responses than those following pseudowords, indicating more effortful processing due to lateral inhibition. Although these effects went in the same direction for hearing and deaf readers, the distribution of the N400 effect differed. We associate the more anterior effect in hearing readers with stronger co-activation of, and competition among, phonological representations. Thus, deaf readers use lexical competition to recognize visual words, but it is primarily restricted to orthographic representations.

Orthographic and phonological selectivity across the reading system in deaf skilled readers

People who are born deaf often have difficulty learning to read. Recently, several studies have examined the neural substrates involved in reading in deaf people and found a left lateralized reading system similar to hearing people involving temporo-parietal, inferior frontal, and ventral occipito-temporal cortices. Previous studies in typical hearing readers show that within this reading network there are separate regions that specialize in processing orthography and phonology. We used fMRI rapid adaptation in deaf adults who were skilled readers to examine neural selectivity in three functional ROIs in the left hemisphere: temporoparietal cortex (TPC), inferior frontal gyrus (IFG), and the visual word form area (VWFA). Results show that in deaf skilled readers, the left VWFA showed selectivity for orthography similar to what has been reported for hearing readers, the TPC showed less sensitivity to phonology than previously reported for hearing readers using the same paradigm, and the IFG showed selectivity to orthography, but not phonology (similar to what has been reported previously for hearing readers). These results provide evidence that while skilled deaf readers demonstrate coarsely tuned phonological representations in the TPC, they develop finely tuned representations for the orthography of written words in the VWFA and IFG. This result suggests that phonological tuning in the TPC may have little impact on the neural network associated with skilled reading for deaf adults.

Verbal Working Memory in Children With Cochlear Implants

PURPOSE

Verbal working memory in children with cochlear implants and children with normal hearing was examined.

PARTICIPANTS

Ninety-three fourth graders (47 with normal hearing, 46 with cochlear implants) participated, all of whom were in a longitudinal study and had working memory assessed 2 years earlier.

METHOD

A dual-component model of working memory was adopted, and a serial recall task measured storage and processing. Potential predictor variables were phonological awareness, vocabulary knowledge, nonverbal IQ, and several treatment variables. Potential dependent functions were literacy, expressive language, and speech-in-noise recognition.

RESULTS

Children with cochlear implants showed deficits in storage and processing, similar in size to those at second grade. Predictors of verbal working memory differed across groups: Phonological awareness explained the most variance in children with normal hearing; vocabulary explained the most variance in children with cochlear implants. Treatment variables explained little of the variance. Where potentially dependent functions were concerned, verbal working memory accounted for little variance once the variance explained by other predictors was removed.

CONCLUSIONS

The verbal working memory deficits of children with cochlear implants arise due to signal degradation, which limits their abilities to acquire phonological awareness. That hinders their abilities to store items using a phonological code.

The N170 ERP component differs in laterality, distribution, and association with continuous reading measures for deaf and hearing readers

The temporo-occipitally distributed N170 ERP component is hypothesized to reflect print-tuning in skilled readers. This study investigated whether skilled deaf and hearing readers (matched on reading ability, but not phonological awareness) exhibit similar N170 patterns, given their distinct experiences learning to read. Thirty-two deaf and 32 hearing adults viewed words and symbol strings in a familiarity judgment task. In the N170 epoch (120-240ms) hearing readers produced greater negativity for words than symbols at left hemisphere (LH) temporo-parietal and occipital sites, while deaf readers only showed this asymmetry at occipital sites. Linear mixed effects regression was used to examine the influence of continuous measures of reading, spelling, and phonological skills on the N170 (120-240ms). For deaf readers, better reading ability was associated with a larger N170 over the right hemisphere (RH), but for hearing readers better reading ability was associated with a smaller RH N170. Better spelling ability was related to larger occipital N170s in deaf readers, but this relationship was weak in hearing readers. Better phonological awareness was associated with smaller N170s in the LH for hearing readers, but this association was weaker and in the RH for deaf readers. The results support the phonological mapping hypothesis for a left-lateralized temporo-parietal N170 in hearing readers and indicate that skilled reading is characterized by distinct patterns of neural tuning to print in deaf and hearing adults.

Early use of phonological codes in deaf readers: An ERP study

Previous studies suggest that deaf readers use phonological information of words when it is explicitly demanded by the task itself. However, whether phonological encoding is automatic remains controversial. The present experiment examined whether adult congenitally deaf readers show evidence of automatic use of phonological information during visual word recognition. In an ERP masked priming lexical decision experiment, deaf participants responded to target words preceded by a pseudohomophone (koral - CORAL) or an orthographic control prime (toral - CORAL). Responses were faster for the pseudohomophone than for the orthographic control condition. The N250 and N400 amplitudes were reduced for the pseudohomophone when compared to the orthographic control condition. Furthermore, the magnitude of both the behavioral and the ERP pseudohomophone effects in deaf readers was similar to that of a group of well-matched hearing controls. These findings reveal that phonological encoding is available to deaf readers from the early stages of visual word recognition. Finally, the pattern of correlations of phonological priming with reading ability suggested that the amount of sub-lexical use of phonological information could be a main contributor to reading ability for hearing but not for deaf readers.

Computerized Sign Language-Based Literacy Training for Deaf and Hard-of-Hearing Children

Strengthening the connections between sign language and written language may improve reading skills in deaf and hard-of-hearing (DHH) signing children. The main aim of the present study was to investigate whether computerized sign language-based literacy training improves reading skills in DHH signing children who are learning to read. Further, longitudinal associations between sign language skills and developing reading skills were investigated. Participants were recruited from Swedish state special schools for DHH children, where pupils are taught in both sign language and spoken language. Reading skills were assessed at five occasions and the intervention was implemented in a cross-over design. Results indicated that reading skills improved over time and that development of word reading was predicted by the ability to imitate unfamiliar lexical signs, but there was only weak evidence that it was supported by the intervention. These results demonstrate for the first time a longitudinal link between sign-based abilities and word reading in DHH signing children who are learning to read. We suggest that the active construction of novel lexical forms may be a supramodal mechanism underlying word reading development.

Young Skilled Deaf Readers Have an Enhanced Perceptual Span in Reading

Recently, Bélanger, Slattery, Mayberry and Rayner (2012) showed, using the moving window paradigm, that profoundly deaf adults have a wider perceptual span during reading relative to hearing adults matched on reading level. This difference might be related to the fact that deaf adults allocate more visual attention to simple stimuli in the parafovea (Bavelier, Dye & Hauser, 2006). Importantly, this reorganization of visual attention in deaf individuals is already manifesting in deaf children (Dye, Hauser & Bavelier, 2009). This leads to questions about the time course of the emergence of an enhanced perceptual span (which is under attentional control; Rayner, 2014; Miellet, O'Donnell, & Sereno, 2009) in young deaf readers. The present research addressed this question by comparing the perceptual spans of young deaf readers (age 7-15) and young hearing children (age 7-15). Young deaf readers, like deaf adults, were found to have a wider perceptual span relative to their hearing peers matched on reading level, suggesting that strong and early reorganization of visual attention in deaf individuals goes beyond the processing of simple visual stimuli and emerges into more cognitively complex tasks, such as reading.

Fingerspelled and Printed Words Are Recoded into a Speech-based Code in Short-term Memory

We conducted three immediate serial recall experiments that manipulated type of stimulus presentation (printed or fingerspelled words) and word similarity (speech-based or manual). Matched deaf American Sign Language signers and hearing non-signers participated (mean reading age = 14-15 years). Speech-based similarity effects were found for both stimulus types indicating that deaf signers recoded both printed and fingerspelled words into a speech-based phonological code. A manual similarity effect was not observed for printed words indicating that print was not recoded into fingerspelling (FS). A manual similarity effect was observed for fingerspelled words when similarity was based on joint angles rather than on handshape compactness. However, a follow-up experiment suggested that the manual similarity effect was due to perceptual confusion at encoding. Overall, these findings suggest that FS is strongly linked to English phonology for deaf adult signers who are relatively skilled readers. This link between fingerspelled words and English phonology allows for the use of a more efficient speech-based code for retaining fingerspelled words in short-term memory and may strengthen the representation of English vocabulary.

The neural underpinnings of reading skill in deaf adults

We investigated word-level reading circuits in skilled deaf readers (N=14; mean reading age=19.5years) and less skilled deaf readers (N=14; mean reading age=12years) who were all highly proficient users of American Sign Language. During fMRI scanning, participants performed a semantic decision (concrete concept?), a phonological decision (two syllables?), and a false-font control task (string underlined?). No significant group differences were observed with the full participant set. However, an analysis with the 10 most and 10 least skilled readers revealed that for the semantic task (vs. control task), proficient deaf readers exhibited greater activation in left inferior frontal and middle temporal gyri than less proficient readers. No group differences were observed for the phonological task. Whole-brain correlation analyses (all participants) revealed that for the semantic task, reading ability correlated positively with neural activity in the right inferior frontal gyrus and in a region associated with the orthography-semantics interface, located anterior to the visual word form area. Reading ability did not correlate with neural activity during the phonological task. Accuracy on the semantic task correlated positively with neural activity in left anterior temporal lobe (a region linked to conceptual processing), while accuracy on the phonological task correlated positively with neural activity in left posterior inferior frontal gyrus (a region linked to syllabification processes during speech production). Finally, reading comprehension scores correlated positively with vocabulary and print exposure measures, but not with phonological awareness scores.