Evidence for a differential interference of noise in sub-lexical and lexical reading routes in healthy participants and dyslexics.

The ineffective exclusion of surrounding noise has been proposed to underlie the reading deficits in developmental dyslexia. However, previous studies supporting this hypothesis focused on low-level visual tasks, providing only an indirect link of noise interference on reading processes. In this study, we investigated the effect of noise on regular, irregular, and pseudoword reading in 23 dyslexic children and 26 age- and IQ-matched controls, by applying the white noise displays typically used to validate this theory to a lexical decision task. Reading performance and eye movements were measured. Results showed that white noise did not consistently affect dyslexic readers more than typical readers. Noise affected more dyslexic than typical readers in terms of reading accuracy, but it affected more typical than dyslexic readers in terms of response time and eye movements (number of fixations and regressions). Furthermore, in typical readers, noise affected more the speed of reading of pseudowords than real words. These results suggest a particular impact of noise on the sub-lexical reading route where attention has to be deployed to individual letters. The use of a lexical route would reduce the effect of noise. A differential impact of noise between words and pseudowords may therefore not be evident in dyslexic children if they are not yet proficient in using the lexical route. These findings indicate that the type of reading stimuli and consequent reading strategies play an important role in determining the effects of noise interference in reading processing and should be taken into account by further studies.

What's in a game: Video game visual-spatial demand location exhibits a double dissociation with reading speed.

This research sought to clarify the nature of the relationship between video game experience, attention, and reading. Previous studies have suggested playing action video games can improve reading ability in children with dyslexia. Other research has linked video game experience with visual-spatial attention, and visual-spatial attention with reading. We hypothesized that the visual-spatial demands of video games may drive relationships with reading through attentional processing. In this experiment we used a hybrid attention/reading task to explore the relationship between video game visual-spatial demands, reading and attention. We also developed novel visual-spatial demand measures using participants' top five played video games for an individual-specific measure of visual demands. Peripheral visual demands in video games were associated with faster reading times, while central visual demands were associated with slower reading times for both phonetic decoding and lexical reading. In addition, video game experience in terms of hours spent playing video games each week interacted with the cueing effect size in the lexical reading condition, with experienced video game players exhibiting a larger cueing effect than participants with less video game experience. These results suggest that exposure to peripheral visual spatial demands in video games may be related to both lexical and sublexical reading processes in hybrid attentional reading tasks such as ours with skilled adult readers, which has implications not only for models of how ventral and dorsal stream reading and visual-spatial attention are integrated, but also for the development of dyslexia diagnostics and remediation.

Tracking reading skills and reading-related skills in dyslexia before (age 5) and after (ages 10-17) diagnosis.

This study had three goals: to examine the stability of deficits in the phonological and lexical routes in dyslexia (group study), to determine the prevalence of dyslexia profiles (multiple-case study), and to identify the prediction of phonemic segmentation and discrimination skills before reading acquisition on future reading level. Among a group of 373 non-readers seen at age 5, 38 students were subsequently diagnosed as either consistent dyslexic readers (18 DYS) or consistent typical readers (20 TR). Their phonological and lexical reading skills were assessed at ages 10 and 17 and their phonemic segmentation and discrimination skills at age 5. In comparison with TR of the same chronological age (CA-TR), individuals with dyslexia demonstrated an impairment of the two reading routes, especially of the phonological reading route. In the comparison with younger TR (age 10) of the same reading level (RL-TR), only a deficit of the phonological route is observed. In the multiple-case study, the comparisons with CA-TR showed a prevalence of mixed profiles and very few dissociated profiles, whereas the comparison with RL-TR resulted mostly in two profiles depending on the measure: a phonological profile when accuracy was used and a delayed profile when speed was used. In addition, the correlations between early phonemic segmentation and discrimination skills (age 5) and later reading skills (age 17) were significant, and in the group of individuals with dyslexia, early phonemic segmentation skills significantly predicted these later reading skills. Phonological reading deficits are persistent and mainly caused by early phonemic impairments.

Where words and space collide: The overlapping neural activation of lexical and sublexical reading with voluntary and reflexive spatial attention.

Recent research has shown a relationship between reading and attention, however the neuroanatomical overlap of these two processes has remained relatively unexplored. Therefore, we sought to investigate the overlapping neural mechanisms of spatial attention and reading using functional magnetic resonance imaging. Participants performed two attentional orienting tasks (reflexive and voluntary), and two overt word-reading tasks (lexical and sublexical). We hypothesized that there would be greater unique activation overlap of reflexive attention with lexical reading, and of voluntary attention with sublexical reading. Results indicated that lexical reading had greater overlapping activation in reflexive orienting areas compared to sublexical reading, suggesting that lexical reading may employ more automatic attentional mechanisms. In contrast, sublexical reading had greater overlapping activation with voluntary attention areas compared to lexical reading, suggesting that phonetic decoding may rely more heavily on voluntary attention. This research broadens our understanding of the neural overlap that underlies the relationship between reading and spatial attention.

How words and space collide: Lexical and sublexical reading are reliant on separable reflexive and voluntary attention regions in hybrid tasks.

Reading ability requires the coordination of many cognitive processes to be effective, including spatial attention. Recent functional magnetic resonance imaging (fMRI) evidence from Ekstrand et al. (2019) suggests that lexical reading is more associated with reflexive attentional orienting regions, whereas sublexical reading is more associated with voluntary attentional orienting regions. The current research sought to further examine the neuroanatomical relationship between reading and attention using a novel experimental design in fMRI. Participants performed four hybrid attentional orienting and reading-aloud tasks, where a reflexive or voluntary spatial cue preceded a lexical or sublexical target. Results indicated that lexical reading resulted in greater activation in the right temporoparietal junction, a reflexive orienting region. Sublexical reading resulted in greater activation in the left inferior frontal gyrus, left fusiform and inferior temporal gyrus, and right superior parietal lobule and intraparietal sulcus (voluntary orienting regions). Further, we found an interaction between reading and attention in the middle occipital gyrus. This study provides the most direct evidence to date that lexical and sublexical reading recruit differential attentional orienting regions during single-word reading in skilled readers. Implications for models of reading and attention, as well as for strategic remediation of their dysfunction, are discussed.

Recruitment of the left precentral gyrus in reading epilepsy: A multimodal neuroimaging study.

PURPOSE: In a previous study, we investigated a 42-year-old male patient with primary reading epilepsy using continuous video-electroencephalography (EEG). Reading tasks induced left parasagittal spikes with a higher spike frequency when the phonological reading pathway was recruited compared to the lexical one. Here, we seek to localize the epileptogenic focus in the same patient as a function of reading pathway using multimodal neuroimaging. METHODS AND RESULTS: The participant read irregular words and nonwords presented in a block-design paradigm during magnetoencephalography (MEG), functional near-infrared spectroscopy (fNIRS), and functional magnetic resonance imaging (fMRI) recordings, all combined with EEG. Spike analyses from MEG, fNIRS, and fMRI-EEGs data revealed an epileptic focus in the left precentral gyrus, and spike localization did not differ in lexical and phonological reading. CONCLUSION: This study is the first to investigate ictogenesis in reading epilepsy during both lexical and phonological reading while using three different multimodal neuroimaging techniques. The somatosensory and motor control functions of the left precentral gyrus that are congruently involved in lexical as well as phonological reading can explain the identical spike localization in both reading pathways. The concurrence between our findings in this study and those from our previous one supports the role of the left precentral gyrus in phonological output computation as well as seizure activity in a case of reading epilepsy.

Lexical and sub-lexical reading skills and their correlation to clinical symptoms in young Chinese patients with schizophrenia.

Patients with schizophrenia often experience severe reading deficits such as oral reading and reading comprehension deficits. However, it is not known whether different types of lexical or sub-lexical components in reading are also impaired. In order to address this issue, the present study had 22 young Chinese patients with schizophrenia and 22 young Chinese normal controls undergo a battery of reading tests, which specifically measures lexical and sub-lexical components of reading in Chinese. The schizophrenic group further underwent Brief Psychiatric Rating Scale (BPRS) in order to ascertain the severity of patients' clinical symptoms. The results showed that compared to the controls, (1) the schizophrenic patients performed significantly poorly in orthographic processing, orthography-phonology mapping, and orthography-semantic mapping tests and further that (2) their performances in orthographic processing, and orthography-semantic mapping skill tests negatively correlated with the BPRS score. Note however that their ability to access their mental lexicon was intact. There is thus a clear need for studies with a larger sample-size and neurobiological measures which would lead to our better understanding of the behavioral as well as the neural relationships between schizophrenic patients, and their reading processing impairments, thus developing effective reading intervention programs for the schizophrenic patients.

Functional near-infrared spectroscopy for the assessment of overt reading.

Functional near-infrared spectroscopy (fNIRS) has become increasingly established as a promising technique for monitoring functional brain activity. To our knowledge, no study has yet used fNIRS to investigate overt reading of irregular words and nonwords with a full coverage of the cerebral regions involved in reading processes. The aim of our study was to design and validate a protocol using fNIRS for the assessment of overt reading. Twelve healthy French-speaking adults underwent one session of fNIRS recording while performing an overt reading of 13 blocks of irregular words and nonwords. Reading blocks were separated by baseline periods during which participants were instructed to fixate a cross. Sources (n = 55) and detectors (n = 16) were placed bilaterally over frontal, temporal, parietal, and occipital regions. Two wavelengths were used: 690 nm, more sensitive to deoxyhemoglobin (HbR) concentration changes, and 830 nm, more sensitive to oxyhemoglobin (HbO) concentration changes. For all participants, total hemoglobin (HbT) concentrations (HbO + HbR) were significantly higher than baseline for both irregular word and nonword reading in the inferior frontal gyri, the middle and superior temporal gyri, and the occipital cortices bilaterally. In the temporal gyri, although the difference was not significant, [HbT] values were higher in the left hemisphere. In the bilateral inferior frontal gyri, higher [HbT] values were found in nonword than in irregular word reading. This activation could be related to the grapheme-to-phoneme conversion characterizing the phonological pathway of reading. Our findings confirm that fNIRS is an appropriate technique to assess the neural correlates of overt reading.