Letter-by-letter readers identify each letter of the word they are reading serially in left to right order before recognizing the word. When their letter naming is also impaired, letter-by-letter reading is inaccurate and can render even single word reading very poor. Tactile and/or kinesthetic strategies have been reported to improve reading in these patients, but only under certain conditions or for a limited set of stimuli.
The primary aim of the current study was to determine whether a tactile/kinesthetic treatment could significantly improve reading specifically under normal reading conditions, i.e. reading untrained words presented in free vision and read without overt use of the strategy.
Methods & Procedures
Three chronic letter-by-letter readers participated in a tactile/kinesthetic treatment aimed at first improving letter naming accuracy (phase 1) and then letter-by-letter reading speed (phase 2). In a multiple case series design, accuracy and speed of reading untrained words without overt use of the trained tactile/kinesthetic strategy was assessed before phase 1, after phase 1 and again after phase 2.
Outcomes & Results
All three patients significantly improved both their speed and accuracy reading untrained words without overt use of the trained tactile/kinesthetic strategy. All three patients required the additional practice in phase 2 to achieve significant improvement. Treatment did not target sentence level reading, yet two of the three patients became so adept that they could read entire sentences.
This study replicates previous findings on the efficacy of tactile/kinesthetic treatment for letter-by-letter readers with poor letter naming. It further demonstrates that this treatment can alter cognitive processing such that words never specifically trained can be read in free vision without overtly using the trained strategy. The data suggest that an important element in achieving this level of generalization is continuing training beyond the point of initial mastery (i.e. accurate letter naming).
aphasia; cognitive rehabilitation; Speech-Language Pathology; pure alexia; letter-by-letter reading; generalization
To develop and validate 28 short Italian sentences for the construction of the Italian version of the Radner Reading Chart to simultaneously measure near visual acuity and reading speed.
41 sentences were constructed in Italian language, following the procedure defined by Radner, to obtain “sentence optotypes” with comparable structure and with the same lexical and grammatical difficulty. Sentences were statistically selected and used in 211 normal, non-presbyopic, native Italian-speaking persons. The most equally matched sentences in terms of reading speed and number of reading errors were selected. To assess the validity of the reading speed results obtained with the 28 selected short sentences, we compared the reading speed and reading errors with the average obtained by reading two long 4th-grade paragraphs (97 and 90 words) under the same conditions.
The overall mean reading speed of the tested persons was 189 ± 26 wpm. The 28 sentences more similar in terms of reading times were selected, achieving a coefficient of variation (the relative SD) of 2.2%. The reliability analyses yielded an overall Cronbach's alpha coefficient of 0.98. The correlation between the short sentences and the long paragraph was high (r = 0.85, P < 0.0001).
The 28 short single Italian sentences optotypes were highly comparable in syntactical structure, number, position, and length of words, lexical difficulty, and reading length. The resulting Italian Radner Reading Chart is precise (high consistency) and practical (short sentences) and therefore useful for research and clinical practice to simultaneously measure near reading acuity and reading speed.
Near vision; Reading acuity; Reading speed; Visual acuity; Visión cercana; Agudeza lectora; Velocidad lectora; Agudeza visual
Although the neural systems supporting single word reading are well studied, there are limited direct comparisons between typical and dyslexic readers of the neural correlates of reading fluency. Reading fluency deficits are a persistent behavioral marker of dyslexia into adulthood. The current study identified the neural correlates of fluent reading in typical and dyslexic adult readers, using sentences presented in a word-by-word format in which single words were presented sequentially at fixed rates. Sentences were presented at slow, medium, and fast rates, and participants were asked to decide whether each sentence did or did not make sense semantically. As presentation rates increased, participants became less accurate and slower at making judgments, with comprehension accuracy decreasing disproportionately for dyslexic readers. In-scanner performance on the sentence task correlated significantly with standardized clinical measures of both reading fluency and phonological awareness. Both typical readers and readers with dyslexia exhibited widespread, bilateral increases in activation that corresponded to increases in presentation rate. Typical readers exhibited significantly larger gains in activation as a function of faster presentation rates than readers with dyslexia in several areas, including left prefrontal and left superior temporal regions associated with semantic retrieval and semantic and phonological representations. Group differences were more extensive when behavioral differences between conditions were equated across groups. These findings suggest a brain basis for impaired reading fluency in dyslexia, specifically a failure of brain regions involved in semantic retrieval and semantic and phonological representations to become fully engaged for comprehension at rapid reading rates.
The present study examined how word-initial letters influence lexical access during reading. Eye movements were monitored as participants read sentences containing target words. Three factors were independently manipulated. First, target words had either high or low constraining word-initial letter sequences (e.g., dwarf or clown, respectively). Second, targets were either high or low in frequency of occurrence (e.g., train or stain, respectively). Third, targets were embedded in either biasing or neutral contexts (i.e., targets were high or low in their predictability). This 2 (constraint) × 2 (frequency) × 2 (context) design allowed us to examine the conditions under which a word’s initial letter sequence could facilitate processing. Analyses of fixation duration data revealed significant main effects of constraint, frequency, and context. Moreover, in measures taken to reflect “early” lexical processing (i.e., first and single fixation duration), there was a significant interaction between constraint and context. The overall pattern of findings suggests lexical access is facilitated by highly constraining word-initial letters. Results are discussed in comparison to recent studies of lexical features involved in word recognition during reading.
reading; eye movements; word-initial letter constraint; word frequency; contextual predictability
People with central vision loss often prefer boldface print over normal print for reading. However, little is known about how reading speed is influenced by the letter-stroke boldness of font. In this study, we examined the reliance of reading speed on stroke boldness, and determined whether this reliance differs between the normal central and peripheral vision. Reading speed was measured using the rapid serial visual presentation paradigm, where observers with normal vision read aloud short single sentences presented on a computer monitor, one word at a time. Text was rendered in Courier at six levels of boldness, defined as the stroke-width normalized to that of the standard Courier font: 0.27, 0.72, 1, 1.48, 1.89 and 3.04× the standard. Testings were conducted at the fovea and 10° in the inferior visual field. Print sizes used were 0.8× and 1.4× the critical print size (smallest print size that can be read at the maximum reading speed). At the fovea, reading speed was invariant for the middle four levels of boldness, but dropped by 23.3% for the least and the most bold text. At 10° eccentricity, reading speed was virtually the same for all boldness <1, but showed a poorer tolerance to bolder text, dropping by 21.5% for 1.89x boldness and 51% for the most bold (3.04x) text. These results could not be accounted for by the changes in print size or the RMS contrast of text associated with changes in stroke boldness. Our results suggest that contrary to the popular belief, reading speed does not benefit from bold text in the normal fovea and periphery. Excessive increase in stroke boldness may even impair reading speed, especially in the periphery.
Reading; stroke boldness; peripheral vision
Phonologic text alexia (PhTA) is a reading disorder in which reading of pseudowords is impaired, but reading of real words is impaired only when reading text. Oral reading accuracy remains well preserved when words are presented individually, but when presented in text the part-of-speech effect that is often seen in phonologic alexia (PhA) emerges.
To determine whether repetition priming could strengthen and/or maintain the activation of words during text reading.
Methods & Procedures
We trained NYR, a patient with PhTA, to use a strategy, Sentence Building, designed to improve accuracy of reading words in text. The strategy required NYR to first read the initial word, and then build up the sentence by adding on sequential words, in a step-wise manner, utilizing the benefits of repetition priming to enhance accuracy.
Outcomes & Results
When using the strategy, NYR displayed improved accuracy not only for sentences she practiced using the strategy, but unpracticed sentences as well. Additionally, NYR performed better on a test of comprehension when using the strategy, as compared to without the strategy.
In light of research linking repetition priming to increased neural processing efficiency, our results suggest that use of this compensatory strategy improves reading accuracy and comprehension by temporarily boosting phonologic activation levels.
phonologic text alexia; repetition priming; aphasia; alexia; rehabilitation
Previous studies used a text-fading procedure as a training tool with the goal to increase silent reading fluency (i.e., proficient reading rate and comprehension). In recently published studies, this procedure resulted in lasting reading enhancements for adult and adolescent research samples. However, studies working with children reported mixed results. While reading rate improvements were observable for Dutch reading children in a text-fading training study, reading fluency improvements in standardized reading tests post-training attributable to the fading manipulation were not detectable. These results raise the question of whether text-fading training is not effective for children or whether research design issues have concealed possible transfer effects. Hence, the present study sought to investigate possible transfer effects resulting from a text-fading based reading training program, using a modified research design. Over a period of 3 weeks, two groups of German third-graders read sentences either with an adaptive text-fading procedure or at their self-paced reading rate. A standardized test measuring reading fluency at the word, sentence, and text level was conducted pre- and post-training. Text level reading fluency improved for both groups equally. Post-training gains at the word level were found for the text-fading group, however, no significant interaction between groups was revealed for word reading fluency. Sentence level reading fluency gains were found for the text-fading group, which significantly differed from the group of children reading at their self-paced reading routine. These findings provide evidence for the efficacy of text-fading as a training method for sentence reading fluency improvement also for children.
reading rate; reading comprehension; training; transfer; intervention
Crowding, the difficulty in recognizing a letter in close proximity with other letters, has been suggested as an explanation for slow reading in people with central vision loss. The goals of this study were (1) to examine whether increased letter spacing in words, which presumably reduces crowding among letters, would benefit reading for people with central vision loss; and (2) to relate our finding to the current account of faulty feature integration of crowding.
Fourteen observers with central vision loss read aloud single sentences, one word at a time, using rapid serial visual presentation (RSVP). Reading speeds were calculated based on the RSVP exposure durations yielding 80% accuracy. Letters were rendered in Courier, a fixed-width font. Observers were tested at 1.4× the critical print size (CPS), three were also tested at 0.8× CPS. Reading speed was measured for five center-to-center letter spacings (range: 0.5–2× the standard spacing). The preferred retinal locus (PRL) for fixation was determined for nine of the observers, from which we calculated the horizontal dimension of the integration field for crowding.
All observers showed increased reading speed with letter spacing for small spacings, until an optimal spacing, beyond which reading speed either showed a plateau, or dropped as letter spacing further increased. The optimal spacing averaged 0.95±0.06× [±95%CI] the standard spacing for 1.4× CPS (similar for 0.8× CPS), which was not different from the standard. When converted to angular size, the measured values of the optimal letter spacing for reading show a good relationship with the calculated horizontal dimension of the integration field.
Increased letter spacing beyond the standard size, which presumably reduces crowding among letters in text, does not improve reading speed for people with central vision loss. The optimal letter spacing for reading can be predicted based on the PRL.
reading; crowding; central vision loss; low vision; age-related macular degeneration
We evaluated the impact of glaucoma on out-loud and silent reading.
Glaucoma patients with bilateral visual field (VF) loss and normally-sighted controls had the following parameters measured: speed reading an International Reading Speed Text (IReST) passage out loud, maximum out-loud MNRead chart reading speed, sustained (30 minutes) silent reading speed, and change in reading speed during sustained silent reading.
Glaucoma subjects read slower than controls on the IReST (147 vs. 163 words per minute [wpm], P < 0.001), MNRead (172 vs. 186 wpm, P < 0.001), and sustained silent (179 vs. 218 wpm, P < 0.001) tests. In multivariable analyses adjusting for age, race, sex, education, employment, and cognition, IReST and MNRead reading speeds were 12 wpm (6%–7%) slower among glaucoma subjects compared to controls (P < 0.01 for both), while sustained silent reading speed was 16% slower (95% confidence interval [CI] = −24 to −6%, P = 0.002). Each 5 decibel (dB) decrement in better-eye VF mean deviation was associated with 6 wpm slower IReST reading (95% CI = −9 to −3%, P < 0.001), 5 wpm slower MNRead reading (95% CI = −7 to −2%, P < 0.001), and 9% slower sustained silent reading (95% CI = −13 to −6%, P < 0.001). A reading speed decline of 0.5 wpm/min or more over the sustained silent reading period was more common among glaucoma subjects than controls (odds ratio [OR] = 2.2, 95% CI = 1.0–4.9, P < 0.05).
Reading speed is slower among glaucoma patients with bilateral VF loss, with the greatest impact present during sustained silent reading. Persons with glaucoma fatigue during silent reading, resulting in slower reading over time.
Bilateral visual field loss from glaucoma is associated with slower reading speed and decline of reading speed during prolonged silent reading. Silent reading speed over prolonged durations is more affected by glaucomatous visual field loss than reading out loud for short durations.
We explored morphological decomposition in reading, the locus in the reading process in which it takes place and its nature, comparing different types of morphemes. We assessed these questions through the analysis of letter position errors in readers with letter position dyslexia (LPD). LPD is a selective impairment to letter position encoding in the early stage of word reading, which results in letter migrations (such as reading “cloud” for “could”). We used the fact that migrations in LPD occur mainly in word-interior letters, whereas exterior letters rarely migrate. The rationale was that if morphological decomposition occurs prior to letter position encoding and strips off affixes, word-interior letters adjacent to an affix (e.g., signs-signs) would become exterior following affix-stripping and hence exhibit fewer migrations. We tested 11 Hebrew readers with developmental LPD and 1 with acquired LPD in 6 experiments of reading aloud, lexical decision, and comprehension, at the single word and sentence levels (compared with 25 age-matched control participants). The LPD participants read a total of 12,496 migratable words. We examined migrations next to inflectional, derivational, or bound function morphemes compared with migrations of exterior letters. The results were that root letters adjacent to inflectional and derivational morphemes were treated like middle letters, and migrated frequently, whereas root letters adjacent to bound function morphemes patterned with exterior letters, and almost never migrated. Given that LPD is a pre-lexical deficit, these results indicate that morphological decomposition takes place in an early, pre-lexical stage. The finding that morphologically complex nonwords showed the same patterns indicates that this decomposition is structurally, rather than lexically, driven. We suggest that letter position encoding takes place before morphological analysis, but in some cases, as with bound function morphemes, the complex word is re-analyzed as two separate words. In this reanalysis, letter positions in each constituent word are encoded separately, and hence the exterior letters of the root are treated as exterior and do not migrate.
morphological decomposition; Hebrew; letter position; inflection; derivation; letter position dyslexia; acquired dyslexia; developmental dyslexia
Pattern-related visual stress (PRVS) is a form of sensory hypersensitivity that some people experience when viewing high contrast repeating patterns, notably alternating dark and light stripes. Those susceptible to PRVS typically have a strong aversion to such stimuli, and this is often accompanied by experiences of visual discomfort and disturbance. The patterns most likely to elicit symptoms of PRVS have a square-wave grating configuration of spatial frequency ~3 cycles/degree. Such stimuli are characteristic of printed text in which lines of words and the spaces between them present a high contrast grating-like stimulus. Consequently, much printed reading material has the potential to elicit PRVS that may impair reading performance, and this problem appears to be common in individuals with reading difficulties including dyslexia. However, the manner in which PRVS affects reading ability is unknown. One possibility is that the early sensory visual stress may interfere with the later cognitive word recognition stage of the reading process, resulting in reading performance that is slower and/or less accurate. To explore the association of PRVS with word recognition ability, lexical decision performance (speed and accuracy) to words and pronounceable non-words was measured in two groups of adults, having low and high susceptibility to PRVS. Results showed that lexical decisions were generally faster but less accurate in high-PRVS, and also that high-PRVS participants made decisions significantly faster for words than for non-words, revealing a strong lexicality effect that was not present in low-PRVS. These findings are novel and, as yet, unconfirmed by other studies.
vision; reading; visual stress; word recognition; lexical decision
It is well known that people with aphasia have sentence comprehension impairments. The present study investigated whether lexical factors contribute to sentence comprehension impairments in both the auditory and written modalities using on-line measures of sentence processing.
People with aphasia and non-brain-damaged controls participated in the experiment (n=8 per group). Twenty-one sentence pairs containing high and low frequency words were presented in self-paced listening and reading tasks. The sentences were syntactically simple and differed only in the critical words. The dependent variables were response times for critical segments of the sentence and accuracy on the comprehension questions.
The results showed that word frequency influences performance on measures of sentence comprehension in people with aphasia. The accuracy data on the comprehension questions suggested that people with aphasia have more difficulty understanding sentences containing low frequency words in the written compared to auditory modality. Both group and single case analyses of the response time data also pointed to more difficulty with reading than listening.
The results show that sentence comprehension in people with aphasia is influenced by word frequency and presentation modality.
We investigated word learning in university and college students with a diagnosis of dyslexia and in typically-reading controls. Participants read aloud short (4-letter) and longer (7-letter) nonwords as quickly as possible. The nonwords were repeated across 10 blocks, using a different random order in each block. Participants returned 7 days later and repeated the experiment. Accuracy was high in both groups. The dyslexics were substantially slower than the controls at reading the nonwords throughout the experiment. They also showed a larger length effect, indicating less effective decoding skills. Learning was demonstrated by faster reading of the nonwords across repeated presentations and by a reduction in the difference in reading speeds between shorter and longer nonwords. The dyslexics required more presentations of the nonwords before the length effect became non-significant, only showing convergence in reaction times between shorter and longer items in the second testing session where controls achieved convergence part-way through the first session. Participants also completed a psychological test battery assessing reading and spelling, vocabulary, phonological awareness, working memory, nonverbal ability and motor speed. The dyslexics performed at a similar level to the controls on nonverbal ability but significantly less well on all the other measures. Regression analyses found that decoding ability, measured as the speed of reading aloud nonwords when they were presented for the first time, was predicted by a composite of word reading and spelling scores (“literacy”). Word learning was assessed in terms of the improvement in naming speeds over 10 blocks of training. Learning was predicted by vocabulary and working memory scores, but not by literacy, phonological awareness, nonverbal ability or motor speed. The results show that young dyslexic adults have problems both in pronouncing novel words and in learning new written words.
word learning; reading; dyslexia; word length; repetition; working memory; phonological awareness
Fourth graders whose silent word reading and/or sentence reading rate was, on average, two-thirds standard deviation below their oral reading of real and pseudowords and reading comprehension accuracy were randomly assigned to treatment (n=7) or wait-listed (n=7) control groups. Following nine sessions combining computerized rapid accelerated-reading program (RAP), which individually tailors rate of written text presentation to comprehension criterion (80%), and self-regulated strategies for attending and engaging, the treated group significantly outperformed the wait-listed group before treatment on (a) a grade-normed, silent sentence reading rate task requiring lexical- and syntactic level processing to decide which of three sentences makes sense; and (b) RAP presentation rates yoked to comprehension accuracy level. Each group improved significantly on these same outcomes from before to after instruction. Attention ratings and working memory for written words predicted post-treatment accuracy, which correlated significantly with the silent sentence reading rate score. Implications are discussed for (a) preventing silent reading disabilities during the transition to increasing emphasis on silent reading, (b) evidence-based approaches for making accommodation of extra time on timed tests requiring silent reading, and (c) combining computerized instruction with strategies for self-regulation during silent reading.
Reading familiar words differs from reading unfamiliar non-words in two ways. First, word reading is faster and more accurate than reading of unfamiliar non-words. Second, effects of letter length are reduced for words, particularly when they are presented in the right visual field in familiar formats. Two experiments are reported in which right-handed participants read aloud non-words presented briefly in their left and right visual fields before and after training on those items. The non-words were interleaved with familiar words in the naming tests. Before training, naming was slow and error prone, with marked effects of length in both visual fields. After training, fewer errors were made, naming was faster, and the effect of length was much reduced in the right visual field compared with the left. We propose that word learning creates orthographic word forms in the mid-fusiform gyrus of the left cerebral hemisphere. Those word forms allow words to access their phonological and semantic representations on a lexical basis. But orthographic word forms also interact with more posterior letter recognition systems in the middle/inferior occipital gyri, inducing more parallel processing of right visual field words than is possible for any left visual field stimulus, or for unfamiliar non-words presented in the right visual field.
word learning; reading; hemispheres; visual fields; word length; case alternation
Following a multi-talker conversation relies on the ability to rapidly and efficiently shift the focus of spatial attention from one talker to another. The current study investigated the listening costs associated with shifts in spatial attention during conversational turn-taking in 16 normally-hearing listeners using a novel sentence recall task. Three pairs of syntactically fixed but semantically unpredictable matrix sentences, recorded from a single male talker, were presented concurrently through an array of three loudspeakers (directly ahead and +/−30° azimuth). Subjects attended to one spatial location, cued by a tone, and followed the target conversation from one sentence to the next using the call-sign at the beginning of each sentence. Subjects were required to report the last three words of each sentence (speech recall task) or answer multiple choice questions related to the target material (speech comprehension task). The reading span test, attention network test, and trail making test were also administered to assess working memory, attentional control, and executive function. There was a 10.7 ± 1.3% decrease in word recall, a pronounced primacy effect, and a rise in masker confusion errors and word omissions when the target switched location between sentences. Switching costs were independent of the location, direction, and angular size of the spatial shift but did appear to be load dependent and only significant for complex questions requiring multiple cognitive operations. Reading span scores were positively correlated with total words recalled, and negatively correlated with switching costs and word omissions. Task switching speed (Trail-B time) was also significantly correlated with recall accuracy. Overall, this study highlights (i) the listening costs associated with shifts in spatial attention and (ii) the important role of working memory in maintaining goal relevant information and extracting meaning from dynamic multi-talker conversations.
spatial attention; speech; cocktail party; switch costs; working memory; cognitive load
Many children with reading difficulties display phonological deficits and struggle to acquire non-lexical reading skills. However, not all children with reading difficulties have these problems, such as children with selective letter position dyslexia (LPD), who make excessive migration errors (such as reading slime as “smile”). Previous research has explored three possible loci for the deficit – the phonological output buffer, the orthographic input lexicon, and the orthographic-visual analysis stage of reading. While there is compelling evidence against a phonological output buffer and orthographic input lexicon deficit account of English LPD, the evidence in support of an orthographic-visual analysis deficit is currently limited. In this multiple single-case study with three English-speaking children with developmental LPD, we aimed to both replicate and extend previous findings regarding the locus of impairment in English LPD. First, we ruled out a phonological output buffer and an orthographic input lexicon deficit by administering tasks that directly assess phonological processing and lexical guessing. We then went on to directly assess whether or not children with LPD have an orthographic-visual analysis deficit by modifying two tasks that have previously been used to localize processing at this level: a same-different decision task and a non-word reading task. The results from these tasks indicate that LPD is most likely caused by a deficit specific to the coding of letter positions at the orthographic-visual analysis stage of reading. These findings provide further evidence for the heterogeneity of dyslexia and its underlying causes.
phonological output deficit; orthographic input lexicon deficit; orthographic-visual analysis deficit; migration errors; substitution errors; developmental dyslexia
To construct and validate a test of sustained silent reading.
Standardized 7300 and 7600 word passages were written to evaluate sustained silent reading. Two hundred forty subjects validated whether comprehension questions could discriminate subjects who did and did not read the passage. To evaluate test–retest properties, 49 subjects silently read the standardized passages on separate days. Sixty glaucoma suspect controls and 64 glaucoma subjects had their out loud reading evaluated with the MNRead card and an International Reading Speed Texts (IReST) passage, and their silent reading measured using the 7300 word passage. Sustained silent reading parameters included reading speed and reading speed slope over time.
Comprehension questions distinguished individuals who had and had not read passage materials. Bland-Altman analyses of intersession sustained reading speed and reading speed slope demonstrated 95% coefficients of repeatability of 57 words per minute (wpm) and 2.76 wpm/minute. Sustained silent reading speed was less correlated with MNRead (r = 0.59) or IReST passage (r = 0.68) reading speeds than the correlation of these two measures of out loud reading speed with each other (r = 0.72). Sustained silent reading speed was more likely to differ from IReST reading speed by more than 50% in rapid silent readers (odds ratio [OR] = 29, 95% confidence interval [CI] = 10–87), and comparisons of sustained and out loud reading speeds demonstrated proportional error in Bland-Altman analyses.
Tests of out loud reading do not accurately reflect silent reading speed in individuals with normal vision or glaucoma. The described test offers a standardized way to evaluate the impact of eye disease and/or visual rehabilitation on sustained silent reading.
Sustained silent reading is not captured well by traditional tests of out loud reading, suggesting fundamental differences between these types of reading. A test to evaluate sustained silent reading is described here, and may be useful in assessing the relationship between reading and vision.
The ability to identify letters and encode their position is a crucial step of the word recognition process. However and despite their word identification problem, the ability of dyslexic children to encode letter identity and letter-position within strings was not systematically investigated. This study aimed at filling this gap and further explored how letter identity and letter-position encoding is modulated by letter context in developmental dyslexia. For this purpose, a letter-string comparison task was administered to French dyslexic children and two chronological age (CA) and reading age (RA)-matched control groups. Children had to judge whether two successively and briefly presented four-letter strings were identical or different. Letter-position and letter identity were manipulated through the transposition (e.g., RTGM vs. RMGT) or substitution of two letters (e.g., TSHF vs. TGHD). Non-words, pseudo-words, and words were used as stimuli to investigate sub-lexical and lexical effects on letter encoding. Dyslexic children showed both substitution and transposition detection problems relative to CA-controls. A substitution advantage over transpositions was only found for words in dyslexic children whereas it extended to pseudo-words in RA-controls and to all type of items in CA-controls. Letters were better identified in the dyslexic group when belonging to orthographically familiar strings. Letter-position encoding was very impaired in dyslexic children who did not show any word context effect in contrast to CA-controls. Overall, the current findings point to a strong letter identity and letter-position encoding disorder in developmental dyslexia.
letter-string processing; letter-position encoding; letter-identity encoding; letter transposition; letter substitution; reading acquisition; dyslexic children
The locus of the deficit of children with dyslexia in dealing with strings of letters may be a deficit at a pre-lexical graphemic level or an inability to bind orthographic and phonological information. We evaluate these alternative hypotheses in two experiments by examining the role of stimulus pronounceability in a lexical decision task (LDT) and in a forced-choice letter discrimination task (Reicher–Wheeler paradigm). Seventeen fourth grade children with dyslexia and 24 peer control readers participated to two experiments. In the LDT children were presented with high-, low-frequency words, pronounceable pseudowords (such as DASU) and unpronounceable non-words (such as RNGM) of 4-, 5-, or 6- letters. No sign of group by pronounceability interaction was found when over-additivity was taken into account. Children with dyslexia were impaired when they had to process strings, not only of pronounceable stimuli but also of unpronounceable stimuli, a deficit well accounted for by a single global factor. Complementary results were obtained with the Reicher–Wheeler paradigm: both groups of children gained in accuracy in letter discrimination in the context of pronounceable primes (words and pseudowords) compared to unpronounceable primes (non-words). No global factor was detected in this task which requires the discrimination between a target letter and a competitor but does not involve simultaneous letter string processing. Overall, children with dyslexia show a selective difficulty in simultaneously processing a letter string as a whole, independent of its pronounceability; however, when the task involves isolated letter processing, also these children can make use of the ortho-phono-tactic information derived from a previously seen letter string. This pattern of findings is in keeping with the idea that an impairment in pre-lexical graphemic analysis may be a core deficit in developmental dyslexia.
developmental dyslexia; lexical decision; Reicher–Wheeler paradigm; pronounceability; global factor; letter string
There is an increasing use of electronic health records in hospitals across the United States. The speed and accuracy of residents in documenting electronic health records has been insufficiently addressed.
We studied resident typing skills at New York Methodist Hospital. Participating residents typed a standard 100-word alphanumerical paragraph of a patient's medical history. Typing skills were assessed by calculating the net words per minute (WPM). Typing skills were categorized as follows: (1) fewer than 26 net WPM as very slow; (2) 26 to 35 net WPM as slow; (3) 35 to 45 net WPM as intermediate; and (4) greater than 45 net WPM as fast. Residents were further categorized into (1) American medical graduates; (2) American international medical graduates; and (3) non-American international medical graduates.
A total of 104 of 280 residents (37%) participated in the study. There was equal representation from various specialties, backgrounds, and all postgraduate levels of training. The median typing speed was 30.4 net WPM. Typing skills were very slow (34 of 104, 33%), slow (28 of 104, 27%), intermediate (29 of 104, 28%), and fast (13 of 104, 12%) among the residents. Typing skills of non-American international medical graduates (mean net WPM of 25.9) were significantly slower than those of American medical graduates (mean net WPM of 35.9) and American international medical graduates (mean net WPM of 33.5).
Most residents (60%, 62 of 104) who participated in the study at our institute lacked typing skills. As the use of electronic health records increases, a lack of typing skills may impact residents' time for learning and patient care.
During natural reading, parafoveal information is processed to some degree. Although isolated words can be fully processed in the parafovea, not all sentence reading experiments have found evidence of semantic processing in the parafovea. We suggest a possible reconciliation for these mixed results via two ERP studies in which volunteers read sentences presented word by word at fixation, flanked bilaterally by the next word to its right and the previous word to its left. Half the words in the right parafovea of critical triads and in the fovea for the subsequent triad were semantically incongruent. The conditions under which parafoveal words elicit canonical visual N400 congruity effects suggest that they are processed in parallel with foveal words, but that the extraction of semantic information parafoveally is a function of contextual constraint and presentation rate, most likely under high contextual constraint and at slower rates.
Reading; parafovea; parafoveal-on-foveal effect; preview benefit; ERPs; N400
To examine multimodal spoken word-in-sentence recognition in children.
Two experiments were undertaken. In Experiment I, the youngest age with which the multimodal sentence recognition materials could be used was evaluated. In Experiment II, lexical difficulty and presentation modality effects were examined, along with test-retest reliability and validity in normal-hearing children and those with cochlear implants.
Normal-hearing children as young as 3.25 years and those with cochlear implants just under 4 years who have used their device for at least 1 year were able to complete the multimodal sentence testing. Both groups identified lexically easy words in sentences more accurately than lexically hard words across modalities, although the largest effects occurred in the auditory-only modality. Both groups displayed audiovisual integration with the highest scores achieved in the audiovisual modality, followed sequentially by auditory-only and visual-only modalities. Recognition of words in sentences was correlated with recognition of words in isolation. Preliminary results suggest fair to good test-retest reliability.
The results suggest that children’s audiovisual word-in-sentence recognition can be assessed using the materials developed for this investigation. With further development, the materials hold promise for becoming a test of multimodal sentence recognition for children with hearing loss.
Letter recognition is the foundation of the human reading system. Despite this, it tends to receive little attention in computational modelling of single word reading. Here we present a model that can be trained to recognise letters in various spatial transformations. When presented with degraded stimuli the model makes letter confusion errors that correlate with human confusability data. Analyses of the internal representations of the model suggest that a small set of learned visual feature detectors support the recognition of both upper case and lower case letters in various fonts and transformations. We postulated that a damaged version of the model might be expected to act in a similar manner to patients suffering from pure alexia. Summed error score generated from the model was found to be a very good predictor of the reading times of pure alexic patients, outperforming simple word length, and accounting for 47% of the variance. These findings are consistent with a hypothesis suggesting that impaired visual processing is a key to understanding the strong word-length effects found in pure alexic patients.
► We develop a connectionist letter recognition model which provides the link between visual input and letter recognition. ► The model can deal with the invariance problem and generalise to previously unseen letters. ► The model can extract key features for letter recognition. ► We demonstrate the model can simulate confusability effects in normal readers and predict PA patients' RTs. ► Impaired visual processing is a key to understanding the strong word-length effects found in PA patients.
Letter recognition; Letter confusability; Pure alexia; Computational modelling
We report (1) the quantitative investigation of text reading in posterior cortical atrophy (PCA), and (2) the effects of 2 novel software-based reading aids that result in dramatic improvements in the reading ability of patients with PCA.
Reading performance, eye movements, and fixations were assessed in patients with PCA and typical Alzheimer disease and in healthy controls (experiment 1). Two reading aids (single- and double-word) were evaluated based on the notion that reducing the spatial and oculomotor demands of text reading might support reading in PCA (experiment 2).
Mean reading accuracy in patients with PCA was significantly worse (57%) compared with both patients with typical Alzheimer disease (98%) and healthy controls (99%); spatial aspects of passages were the primary determinants of text reading ability in PCA. Both aids led to considerable gains in reading accuracy (PCA mean reading accuracy: single-word reading aid = 96%; individual patient improvement range: 6%–270%) and self-rated measures of reading. Data suggest a greater efficiency of fixations and eye movements under the single-word reading aid in patients with PCA.
These findings demonstrate how neurologic characterization of a neurodegenerative syndrome (PCA) and detailed cognitive analysis of an important everyday skill (reading) can combine to yield aids capable of supporting important everyday functional abilities.
Classification of evidence:
This study provides Class III evidence that for patients with PCA, 2 software-based reading aids (single-word and double-word) improve reading accuracy.