Developmental dyslexics show altered allocation of attention in visual classification tasks.
OBJECTIVE
Event-related brain potentials (ERPs) were recorded to investigate allocation of attention in adult developmental dyslexics.


METHODS
Twelve adult developmental dyslexics and 12 matched normal controls performed three visual choice reaction tasks. In the passive oddball condition, subjects watched two different simple visual stimuli presented with 87.5 and 12.5% probability. In the active oddball condition, participants responded to the low-probability target stimulus. In the active 50/50-condition, both stimuli were presented with 50% probability and a response was required to the target stimulus only.


RESULTS
No group differences emerged for performance, P300 latency or laterality and for N200 amplitude, latency or laterality. An enhancement of P300 amplitude with a frontal distribution was found for NoGo (standard)-stimuli in both active conditions for the dyslexic sample.


CONCLUSIONS
Results are discussed in the context of deviances in allocation of attentional resources in dyslexic readers.
Rüsseler
J
J
Department of Neuropsychology, Otto-von-Guericke University, Magdeburg, Germany. jashca.russeler@nat.uni-magdeburg.de
Johannes
S
S
Kowalczuk
J
J
Wieringa
B M
BM
Münte
T F
TF
D000328:Adult; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology; D004193:Discrimination Learning / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D004410:Dyslexia / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009433:Neural Inhibition / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011337:Probability Learning; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology