THE INFLUENCE OF ATTENTION ON THE DICHOTIC REA WITH NORMAL AND LEARNING-DISABLED CHILDREN

Recently, MONDOR and BRYDEN (Neuropsychologia, 29, 1179-1190, 1991; Pe rcept. Psychophys. 52, 393-402, 1992) developed a lateralized cueing t echnique Which appears to be a more powerful method than is the forced -attention technique (Bryden, 1978) of controlling the contribution of attentional biases to auditory perceptual asymmetries. This lateraliz ed cueing technique was used to determine the influence of attentional biases on perceptual asymmetries obtained for normal and specific lea rning disabled (LD) children. Subjects were instructed to attend to, a nd report from, only the ear in which the cue sounded. The interval be tween the onset of the cue and the onset of the dichotic trial is vari ed so as to control the amount of time available to subjects to alloca te attention to the cued ear. Results indicated that, for normal child ren capable of performing the task at a better than chance level, a la rge REA apparent at 150 msec Stimulus Onset Asynchromy (SOA) was atten uated at longer cueing intervals (450 and 750 msec SOA). For LD childr en, the magnitude of the initial REA appeared to be attenuated at 450 msec SOA. Thus, these data demonstrate that for normal children as wel l as for children with specific learning disabilities, attentional fac tors may contribute to the magnitude of the REA.