Rapidly changing environments in day-to-day activities, enriched with stimuli competing for attention, require a cognitive control mechanism to select relevant stimuli, ignore irrelevant stimuli, and shift attention between alternative features of the environment. Such attentional orchestration is essential to the acquisition of reading skills. In…

The aims of this study were to analyze the relationship between dyslexia and eye movements and to assess whether this method can be added to the workup of dyslexic patients. The sample was comprised of 11 children with a diagnosis of dyslexia and 11 normal between 8 and 13 years of age. All subjects underwent orthoptic evaluation, ophthalmological…

This study examined the differences in processing between regular and dyslexic readers in a lexical decision task in different visual field presentations (left, right, and center). The research utilized behavioral measures that provide information on accuracy and reaction time and electro-physiological measures that permit the examination of brain…

Functional transcranial Doppler ultrasound (fTCD) is a relatively new and non-invasive technique that assesses cerebral lateralisation through measurements of blood flow velocity in the middle cerebral arteries. In this study fTCD was used to compare functional asymmetry during a word generation task between a group of 30 dyslexic adults and a…

Temporal and spatial attentional deficits in dyslexia were investigated using a lateralized visual temporal order judgment (TOJ) paradigm that allowed both sensitivity to temporal order and spatial attentional bias to be measured. Findings indicate that adult participants with a positive screen for dyslexia were significantly less sensitive to the…

Studies have reported a right visual field (RVF) advantage for coherent motion detection by deaf and hearing signers but not non-signers. Yet two studies [Bosworth R. G., & Dobkins, K. R. (2002). Visual field asymmetries for motion processing in deaf and hearing signers. "Brain and Cognition," 49, 170-181; Samar, V. J., & Parasnis, I. (2005).…

In an effort to explore S. Orton's "intergrading" hypothesis, six developmental dyslexics (ages 16 to 47) and four good readers were tested on measures of interhemispheric coordination. Dyslexics showed reduced laterality bias and longer response latencies to bihemifield stimuli. (Author/DB)

Reports a study of the lateral preferences and left minus right hand movement time of 129 pupils attending a dyslexia clinic for remedial teaching, and the incidences of left handedness and developmental language problems in relatives. (RH)

Autopsy analysis of eight dyslexic brains found that the ordinary asymmetry in a language-relevant area of the temporal lobe was missing. The greater development of the right side may reflect an increase in the total number of neurons involved in language processing, resulting in changes in interhemispheric interactions. (JDD)

Twelve males (ages 8-12) with phonological dyslexia were compared to 12 age-matched good readers and 12 reading-matched students. Results showed that dyslexia is not related to incomplete lateralization or to a failure to inhibit verbal processing in the right hemisphere during reading and writing. (Author/JDD)

Notes that high-resolution magnetic resonance imaging allows in vivo quantification of the surface area of the cortex covering the planum temporale. Reviews the definition of planum asymmetry as it relates to structural accompaniments of disorders such as developmental dyslexia and to anatomic and functional lateralization. Finds support for the…

Five theories were tested relating to the suspected connection between organic brain dysfunction and poor reading, or dyslexia. Results failed to support the poor lateralization, right hemisphere, global, imbalance theories. Among juvenile offenders, poor reading appears to relate to left-hemisphere dysfunction. (Author)

Twenty-eight L-dyslexic and 26 P-dyslexic children (mean age of 9-10) received hemisphere-specific stimulation (HSS) by presentation of words to right and left fingers, respectively. Relative to controls, HSS-treated L-dyslexic subjects showed larger improvement of accuracy in text reading, whereas HSS-treated P-dyslexic subjects showed more…

Evaluates a substantially updated version of the "classical" idea of a significant relationship in dyslexic children between cerebral lateralization and their word decoding deficits. Finds further evidence that dyslexia is not related to incomplete lateralization. Suggests that dyslexics suffer from exuberant right hemisphere processing in…

Family histories of 12 hyperlexic (precocious word reading with little comprehension often associated with autism) children (5-10 years old) were investigated. Results suggested familial tendencies to disorders of language, reading, writing, and spelling in male relatives, along with a high incidence of nonright-handedness. (Author/DB)