Inquiry into the incidence of hyperlexia in a statewide population of children with pervasive developmental disorder

Measuring the Emergence of Specific Abilities in Young Children with Autism Spectrum Disorders: The Example of Early Hyperlexic Traits

The presence of a restricted interest in written materials, including an early ability to name and recognize letters and numbers, is regularly reported in preschoolers with autism spectrum disorders (ASDs). There is, however, scarce information on this early ability akin to emerging hyperlexic traits in preschoolers with ASD younger than 3 years old. Here, we defined a measure of early naming and recognition of letters and numbers in 155 preschoolers with ASD using a sliding window approach combined with a 90th percentile threshold criterion, and subsequently compared the profiles of children with ASD with and without early hyperlexic traits. Using this measure, we found that 9% of children with ASD showed early hyperlexic traits. The early ability to name and recognize letters and numbers was associated with a higher level of restricted and repetitive behaviors yet more social-oriented behaviors at baseline and with better expressive and written communication at baseline and one year later. This study contributes to a better definition of the profile of children with ASD with an early ability in letters and numbers akin to emerging hyperlexic traits, a skill that is associated with promising social strengths and language abilities in this subgroup of children.

Reading and math achievement profiles and longitudinal growth trajectories of children with an autism spectrum disorder

This study examined the reading and math achievement profiles and longitudinal growth trajectories of a nationally representative sample of children ages 6 through 9 with an autism spectrum disorder. Four distinct achievement profiles were identified: higher-achieving (39%), hyperlexia (9%), hypercalculia (20%) and lower-achieving (32%). Children with hypercalculia and lower-achieving profiles were more likely to be from low socioeconomic families and had lower functional cognitive skills than the higher-achieving profile. All four profiles lost ground in passage comprehension over time. Slower improvement occurred for the higher-achieving group on letter–word identification, the hyperlexia group on conversation abilities and the hypercalculia group on calculation and functional cognitive skills relative to the lower-achieving group.

A comparison of textual and echoic prompts on the acquisition of intraverbal behavior in a six-year-old boy with autism

A comparison of textual and echoic prompts was conducted to determine which form of prompts was more effective for teaching intraverbal behavior to a 6-year-old boy with autism. A multiple baseline design across three sets of questions measured (a) the number of full-sentence target answers, (b) partial answers that made sense, and (c) partial answers that did not make sense, or no response, to direct questions asked. A fading procedure using either scripted textual or scripted echoic prompts was employed to evoke the child's correct answers. Although both forms of prompts were effective, results indicated that textual prompts were much more effective. These findings suggest that textual prompts may be effective in teaching complex skills to children with autism.

Atypical neural specialization for social percepts in autism spectrum disorder

The social motivation hypothesis posits that aberrant neural response to human faces in autism is attributable to atypical social development and consequently reduced exposure to faces. The specificity of deficits in neural specialization remains unclear, and alternative theories suggest generalized processing difficulties. The current study contrasted neural specialization for social information versus nonsocial information in 36 individuals with autism and 18 typically developing individuals matched for age, race, sex, handedness, and cognitive ability. Event-related potentials elicited by faces, inverted faces, houses, letters, and pseudoletters were recorded. Groups were compared on an electrophysiological marker of neural specialization (N170), as well as behavioral performance on standardized measures of face recognition and word reading/decoding. Consistent with prior results, individuals with autism displayed slowed face processing and decreased sensitivity to face inversion; however, they showed comparable brain responses to letters, which were associated with behavioral performance in both groups. Results suggest that individuals with autism display atypical neural specialization for social information but intact specialization for nonsocial information. Findings concord with the notion of specific dysfunction in social brain systems rather than nonspecific information-processing difficulties in autism.

Enhanced visual functioning in autism: an ALE meta-analysis

Autistics often exhibit enhanced perceptual abilities when engaged in visual search, visual discrimination, and embedded figure detection. In similar fashion, while performing a range of perceptual or cognitive tasks, autistics display stronger physiological engagement of the visual system than do non-autistics. To account for these findings, the Enhanced Perceptual Functioning Model proposes that enhanced autistic performance in basic perceptual tasks results from stronger engagement of sensory processing mechanisms, a situation that may facilitate an atypically prominent role for perceptual mechanisms in supporting cognition. Using quantitative meta-analysis of published functional imaging studies from which Activation Likelihood Estimation maps were computed, we asked whether autism is associated with enhanced task-related activity for a broad range of visual tasks. To determine whether atypical engagement of visual processing is a general or domain-specific phenomenon, we examined three different visual processing domains: faces, objects, and words. Overall, we observed more activity in autistics compared to non-autistics in temporal, occipital, and parietal regions. In contrast, autistics exhibited less activity in frontal cortex. The spatial distribution of the observed differential between-group patterns varied across processing domains. Autism may be characterized by enhanced functional resource allocation in regions associated with visual processing and expertise. Atypical adult organizational patterns may reflect underlying differences in developmental neural plasticity that can result in aspects of the autistic phenotype, including enhanced visual skills, atypical face processing, and hyperlexia.

Myth and Reality of the Word Caller: The Relation Between Teacher Nominations and Prevalence Among Elementary School Children

The purpose of the study was to investigate (a) the prevalence of word callers in elementary school, (b) the accuracy of teachers' word caller nominations, and (c) teachers' conceptualization of reading fluency and reading comprehension. To this end, 2 cross-sectional studies of second- and third- (N = 868) and of third- and fifth-grade (N = 202) children were conducted. Our findings suggest that word callers occur infrequently in the primary grades but that they are more prevalent in late elementary school. Regardless of grade level, teachers often overnominated children as word callers. Furthermore, a great deal of ambiguity and inconsistency seems to exist regarding teachers' understanding and use of the term. These findings suggest that the term should be used relatively rarely and that reading educators should be cautious about their identification of word callers in early elementary school.

Orthographic and phonological pathways in hyperlexic readers with Autism Spectrum Disorders

Children with Autism Spectrum Disorders (ASD) often present poor text comprehension relative to their ability to read individual words. Some of them have been considered hyperlexic because of their oustanding word-reading abilities. Although it has been suggested that these children access word reading in an atypical way, there is conflicting evidence on their use of phonological and orthograhic pathways. Fourteen adolescents with ASD with word reading to text comprehension discrepancy and 12 typically developing children, all matched on word reading and chronological age, were administered different lexical and sublexical tasks exploring semantic, orthographic, and phonological word representations and processes. No differences were found on any of the tasks between the children with ASD and the typically developing group. The children with ASD were further subdivided into two groups matched on word reading, one with outstanding word reading rela0tive to verbal IQ and another with word reading consistent with verbal IQ. The first group outperformed the second on tasks involving lexical orthographic and phonological representation. However, they were no different on sub-lexical phonological processing, on rapid naming or working, and short-term memory tasks.

The Neural Basis of Hyperlexic Reading

Children with autism spectrum disorders in very rare cases display surprisingly advanced "hyperlexic" reading skills. Using functional magnetic resonance imaging (fMRI), we studied the neural basis of this precocious reading ability in a 9-year-old hyperlexic boy who reads 6 years in advance of his age. During covert reading, he demonstrated greater activity in the left inferior frontal and superior temporal cortices than both chronological age- and reading age-matched controls. Activity in the right inferior temporal sulcus was greater when compared to reading age-matched controls. These findings suggest that precocious reading is brought about by simultaneously drawing on both left hemisphere phonological and right hemisphere visual systems, reconciling the two prevailing, but seemingly contradictory, single hemisphere theories of hyperlexia. Hyperlexic reading is therefore associated with hyperactivation of the left superior temporal cortex, much in the same way as developmental dyslexia is associated with hypoactivation of this area.

Annotation: Hyperlexia: disability or superability?

BACKGROUND

Hyperlexia is the phenomenon of spontaneous and precocious mastery of single-word reading that has been of interest to clinicians and researchers since the beginning of the last century.

METHODS

An extensive search of publications on the subject of hyperlexia was undertaken and all available publications were reviewed.

RESULTS

The literature can be subdivided into discussions of the following issues: (1) whether hyperlexia is a phenomenon that is characteristic only of specific clinical populations (e.g., children with developmental delays) or whether it can also be observed in the general population; (2) whether hyperlexia is a distinct syndrome comorbid with a number of different disorders or whether it is a part of the spectrum of some other clinical condition(s); (3) whether hyperlexia should be defined through single-word reading superiority with regard to reading comprehension, vocabulary, general intelligence, any combination of the three, or all three characteristics; (4) whether there is a specific neuropsychological profile associated with hyperlexia; (5) whether hyperlexia is characterized by a particular developmental profile; and (6) whether hyperlexia should be viewed as a disability (deficit) or superability (talent).

CONCLUSIONS

We interpret the literature as supporting the view that hyperlexia is a superability demonstrated by a very specific group of individuals with developmental disorders (defined through unexpected single-word reading in the context of otherwise suppressed intellectual functioning) rather than as a disability exhibited by a portion of the general population (defined through a discrepancy between levels of single-word reading and comprehension). We simultaneously argue, however, that multifaceted and multi-methodological approaches to studying the phenomenon of hyperlexia, defined within the research framework of understanding single-word reading, are warranted and encouraged.

A descriptive study of hyperlexia in a clinically referred sample of children with developmental delays

In this study, we evaluated the incidence of hyperlexia in a clinically referred sample of 80 children with developmental delays. Based on hypotheses previously formulated in the literature, the study investigated the frequency of hyperlexia among boys and girls, the incidence of hyperlexia in children with Pervasive Developmental Disorders (PDD)-spectrum compared with non-PDD diagnoses, the range of IQ and of various cognitive skills in children with and without hyperlexia, and the developmental outcomes of children with and without hyperlexia. The results revealed no significant differences in the frequency of hyperlexia in girls compared with boys. However, the frequency of hyperlexia was significantly elevated among children with PDD compared with children with non-PDD diagnoses. The range of IQ and other cognitive skills and the developmental outcomes of children with hyperlexia were comparable to those of children without hyperlexia.

Familial pervasive development disorder, Tourette disorder and hyperlexia

Four children and one adult have been found to have Pervasive Developmental Disorder, Tourette disorder and hyperlexia in North Dakota, a state with a population of 204,161 children ages 0-18. Assuming that these are independent disorders the probability of these three disorders occurring by chance in one child is 3.39 x 10(-12). Two of these individuals are from the same family. This suggests evidence for genetic linkage among these three disorders.