Wide and diffuse perceptual modes characterize dyslexics in vision and audition.
We examined the performance of dyslexic and typically reading children on two analogous recognition tasks: one visual and the other auditory. Both tasks required recognition of centrally and peripherally presented stimuli. Dyslexics recognized letters visually farther in the periphery and more diffuse near the center than typical readers did. Both groups performed comparably in recognizing centrally spoken stimuli presented without peripheral interference, but in the presence of a surrounding speech mask (the 'cocktail-party effect') dyslexics recognized the central stimuli significantly less well than typical readers. However, dyslexics had a higher ratio of the number of words recognized from the surrounding speech mask, relative to the ones from the center, than typical readers did. We suggest that the evidence of wide visual and auditory perceptual modes in dyslexics indicates wider multi-dimensional neural tuning of sensory processing interacting with wider spatial attention.
Geiger
Gadi
G
Centre for Biological and Computational Learning and the McGovern Institute for Brain Research-Brain and Cognitive Sciences, Massachusetts Institute of Technology, Room 46-5162, Cambridge, MA 02139, USA. gadi@ai.mit.edu
Cattaneo
Carmen
C
Galli
Raffaella
R
Pozzoli
Uberto
U
Lorusso
Maria Luisa
ML
Facoetti
Andrea
A
Molteni
Massimo
M
D000161:Acoustic Stimulation / Q000379:methods; D000293:Adolescent; D002648:Child; D004410:Dyslexia / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual; D010470:Perceptual Masking; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D011932:Reading; D013067:Speech Perception