J. S. H. Taylor

A longitudinal investigation of early reading and language skills in children with poor reading comprehension.

BACKGROUND Poor comprehenders have difficulty comprehending connected text, despite having age-appropriate levels of reading accuracy and fluency. We used a longitudinal design to examine earlier reading and language skills in children identified as poor comprehenders in mid-childhood. METHOD Two hundred and forty-two children began the study at age 5. Further assessments of language and reading skill were made at 5.5, 6, 7 and 8 years. At age 8, fifteen children met criteria for being a poor comprehender and were compared to 15 control children both concurrently and prospectively. RESULTS Poor comprehenders showed normal reading accuracy and fluency at all ages. Reading comprehension was poor at each time point and, notably, showed minimal increases in raw score between 6 and 8 years. Phonological skills were generally normal throughout, but mild impairments in expressive and receptive language, listening comprehension and grammatical understanding were seen at all ages. CONCLUSIONS Children identified as poor comprehenders at 8 years showed the same reading profile throughout earlier development. Their difficulties with the non-phonological aspects of oral language were present at school entry and persisted through childhood, showing that the oral language weaknesses seen in poor comprehenders in mid-childhood are not a simple consequence of their reading comprehension impairment.

Can cognitive models explain brain activation during word and pseudoword reading? A meta-analysis of 36 neuroimaging studies.

Reading in many alphabetic writing systems depends on both item-specific knowledge used to read irregular words (sew, yacht) and generative spelling-sound knowledge used to read pseudowords (tew, yash). Research into the neural basis of these abilities has been directed largely by cognitive accounts proposed by the dual-route cascaded and triangle models of reading. We develop a framework that enables predictions for neural activity to be derived from cognitive models of reading using 2 principles: (a) the extent to which a model component or brain region is engaged by a stimulus and (b) how much effort is exerted in processing that stimulus. To evaluate the derived predictions, we conducted a meta-analysis of 36 neuroimaging studies of reading using the quantitative activation likelihood estimation technique. Reliable clusters of activity are localized during word versus pseudoword and irregular versus regular word reading and demonstrate a great deal of convergence between the functional organization of the reading system put forward by cognitive models and the neural systems activated during reading tasks. Specifically, left-hemisphere activation clusters are revealed reflecting orthographic analysis (occipitotemporal cortex), lexical and/or semantic processing (anterior fusiform, middle temporal gyrus), spelling-sound conversion (inferior parietal cortex), and phonological output resolution (inferior frontal gyrus). Our framework and results establish that cognitive models of reading are relevant for interpreting neuroimaging studies and that neuroscientific studies can provide data relevant for advancing cognitive models. This article thus provides a firm empirical foundation from which to improve integration between cognitive and neural accounts of the reading process.

Interpreting response time effects in functional imaging studies

It has been suggested that differential neural activity in imaging studies is most informative if it is independent of response time (RT) differences. However, others view RT as a behavioural index of key cognitive processes, which is likely linked to underlying neural activity. Here, we reconcile these views using the effort and engagement framework developed by Taylor, Rastle, and Davis (2013) and data from the domain of reading aloud. We propose that differences in neural engagement should be independent of RT, whereas, differences in neural effort should co-vary with RT. We illustrate these different mechanisms using data from an fMRI study of neural activity during reading aloud of regular words, irregular words, and pseudowords. In line with our proposals, activation revealed by contrasts designed to tap differences in neural engagement (e.g., words are meaningful and therefore engage semantic representations more than pseudowords) survived correction for RT, whereas activation for contrasts designed to tap differences in neural effort (e.g., it is more difficult to generate the pronunciation of pseudowords than words) correlated with RT. However, even for contrasts designed to tap neural effort, activity remained after factoring out the RT–BOLD response correlation. This may reveal unpredicted differences in neural engagement (e.g., learning phonological forms for pseudowords > words) that could further the development of cognitive models of reading aloud. Our framework provides a theoretically well-grounded and easily implemented method for analysing and interpreting RT effects in neuroimaging studies of cognitive processes.

How Word Meaning Influences Word Reading

Understanding how we read is a fundamental question for psychology, with critical implications for education. Studies of word reading tend to focus on the mappings between the written and spoken forms of words. In this article, we review evidence from developmental, neuroimaging, neuropsychological, and computational studies that show that knowledge of word meanings is inextricably involved in word reading. Consequently, models of reading must better specify the role of meaning in skilled reading and its acquisition. Further, our review paves the way for educationally realistic research to confirm whether explicit teaching of oral vocabulary improves word reading.

Distinct neural specializations for learning to read words and name objects

Understanding the neural systems that underpin reading acquisition is key if neuroscientific findings are to inform educational practice. We provide a unique window into these systems by teaching 19 adults to read 24 novel words written in unfamiliar letters and to name 24 novel objects while in an MRI scanner. Behavioral performance on trained items was equivalent for the two stimulus types. However, componential letter-sound associations were extracted when learning to read, as shown by correct reading of untrained words, whereas object–name associations were holistic and arbitrary. Activity in bilateral anterior fusiform gyri was greater during object name learning than learning to read, and ROI analyses indicated that left mid-fusiform activity was predictive of success in object name learning but not in learning to read. In contrast, activity in bilateral parietal cortices was predictive of success for both stimulus types but was greater during learning and recall of written word pronunciations relative to object names. We argue that mid-to-anterior fusiform gyri preferentially process whole items and contribute to learning their spoken form associations, processes that are required for skilled reading. In contrast, parietal cortices preferentially process componential visual–verbal mappings, a process that is crucial for early reading development.

Comparing and validating methods of reading instruction using behavioural and neural findings in an artificial orthography

There is strong scientific consensus that emphasizing print-to-sound relationships is critical when learning to read alphabetic languages. Nevertheless, reading instruction varies across English-speaking countries, from intensive phonic training to multicuing environments that teach sound- and meaning-based strategies. We sought to understand the behavioral and neural consequences of these differences in relative emphasis. We taught 24 English-speaking adults to read 2 sets of 24 novel words (e.g., /buv/, /sig/), written in 2 different unfamiliar orthographies. Following pretraining on oral vocabulary, participants learned to read the novel words over 8 days. Training in 1 language was biased toward print-to-sound mappings while training in the other language was biased toward print-to-meaning mappings. Results showed striking benefits of print–sound training on reading aloud, generalization, and comprehension of single words. Univariate analyses of fMRI data collected at the end of training showed that print–meaning relative to print–sound relative training increased neural effort in dorsal pathway regions involved in reading aloud. Conversely, activity in ventral pathway brain regions involved in reading comprehension was no different following print–meaning versus print–sound training. Multivariate analyses validated our artificial language approach, showing high similarity between the spatial distribution of fMRI activity during artificial and English word reading. Our results suggest that early literacy education should focus on the systematicities present in print-to-sound relationships in alphabetic languages, rather than teaching meaning-based strategies, in order to enhance both reading aloud and comprehension of written words.

Evaluating cognitive models of visual word recognition using fMRI: Effects of lexical and sublexical variables

In this study predictions of the dual-route cascaded (DRC) model of word reading were tested using fMRI. Specifically, patterns of co-localization were investigated: (a) between pseudoword length effects and a pseudowords vs. fixation contrast, to reveal the sublexical grapho-phonemic conversion (GPC) system; and (b) between word frequency effects and a words vs. pseudowords contrast, to reveal the orthographic and phonological lexicon. Forty four native speakers of Greek were scanned at 3T in an event-related lexical decision task with three event types: (a) 150 words in which frequency, length, bigram and syllable frequency, neighborhood, and orthographic consistency were decorrelated; (b) 150 matched pseudowords; and (c) fixation. Whole-brain analysis failed to reveal the predicted co-localizations. Further analysis with participant-specific regions of interest defined within masks from the group contrasts revealed length effects in left inferior parietal cortex and frequency effects in the left middle temporal gyrus. These findings could be interpreted as partially consistent with the existence of the GPC system and phonological lexicon of the model, respectively. However, there was no evidence in support of an orthographic lexicon, weakening overall support for the model. The results are discussed with respect to the prospect of using neuroimaging in cognitive model evaluation.

Structural properties of the ventral reading pathways are associated with morphological processing in adult English readers

Morphological processing, the ability to extract information about word structure, is an essential component of reading. Functional MRI studies have identified several cortical regions involved in morphological processing, but the white matter pathways that support this skill remain unknown. Here, we examine the relationship between behavioral measures of morphological processing and microstructural properties of white matter pathways. Using diffusion MRI (dMRI), we identified the major ventral and dorsal reading pathways in a group of 45 adult English readers. The same participants completed a behavioral battery that included a morphological task and measures of phonological and orthographic processing. We found significant correlations between morphological processing skill and microstructural properties of the ventral, but not dorsal, pathways. These correlations were detected primarily in the left hemisphere, and remained significant after controlling for phonological or orthographic measures, suggesting some level of cognitive specificity. Morphological processing of written words thus appears to rely on ventral pathways, primarily in the left hemisphere. This finding supports the contribution of morphological processing to lexical access and comprehension of complex English words.

Semantic and phonological schema influence spoken word learning and overnight consolidation

We studied the initial acquisition and overnight consolidation of new spoken words that resemble words in the native language (L1) or in an unfamiliar, non-native language (L2). Spanish-speaking participants learned the spoken forms of novel words in their native language (Spanish) or in a different language (Hungarian), which were paired with pictures of familiar or unfamiliar objects, or no picture. We thereby assessed, in a factorial way, the impact of existing knowledge (schema) on word learning by manipulating both semantic (familiar vs unfamiliar objects) and phonological (L1- vs L2-like novel words) familiarity. Participants were trained and tested with a 12-hr intervening period that included overnight sleep or daytime awake. Our results showed (1) benefits of sleep to recognition memory that were greater for words with L2-like phonology and (2) that learned associations with familiar but not unfamiliar pictures enhanced recognition memory for novel words. Implications for complementary systems accounts of word learning are discussed.

Print-sound regularities are more important than print-meaning regularities in the initial stages of learning to read: Response to Bowers & Bowers (2018):

We previously reported an artificial language learning study designed to compare methods of reading instruction that emphasise learning the relationship between spelling and sound versus learning the relationship between spelling and meaning. Behavioural and neural data supported emphasis on spelling-sound knowledge, and we therefore advocated use of phonics in the initial stages of learning to read. Bowers and Bowers argue that these conclusions are not justified because we (a) mischaracterised the English writing system and (b) mischaracterised the meaning-based instruction used in schools. In this article, we respond to the first point by showing that the novel words used previously were a good approximation to the types of written words that children are exposed to in the first year of reading instruction. We respond to the second point by showing that while enhancements to meaning-based instruction can assist pupils to infer the meanings of unfamiliar words, these methods actually disadvantage long-term learning of those words. We conclude by suggesting that reading instruction should be based on an understanding of the writing system, properly characterised across the trajectory of learning. This means emphasis on spelling-sound regularities in the initial stage of learning to read and increasing emphasis on spelling-meaning regularities as children gain greater experience with text.