Purchase this article with an account.
Gadi Geiger, Carmen Cattaneo, Raffaella Galli, Uberto Pozzoli, Maria Luisa Lorusso, Andrea Facoetti, Silvia Pesenti, Massimo Molteni; A common generalized perceptual strategy? The evidence from dyslexics. Journal of Vision 2002;2(7):671. doi: 10.1167/2.7.671.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Sensory information processing is considered modality specific with limited cross interactions. This is clear in the early input levels. However, for the performance of a task, which involves multi-sensory-modalities, is there a common generalized perceptual strategy, which governs the processing in each modality or, is the strategy modality specific with cross interactions?
Previously it was shown that the extent of visual letter-recognition is larger for dyslexics than for ordinary readers (OR). That is, OR demonstrate focal attention while dyslexics a wide spread attention (e.g. Geiger et al. 1992). This difference was also shown in the tactile domain (Grant et al. 1999).
To determine if childen who are dyslexic or OR have analogous differences in auditory perception we tested both groups in recognition of centrally located spoken stimuli. Our tests had five conditions: 1. recognizing the central stimuli alone, 2. recognizing it in the presence of conversation-background in the periphery, 3. in the presence of chopped-speech background, 4. in the presence of white noise background and 5. repeat of condition 2 while also counting the words perceived from the background.
The results show larger drop of stimuli recognition in the presence of conversation-background for dyslexics than for OR. However, dyslexics perceived more words from the background than OR did. This suggests a wide spread auditory attention for dyslexics and a focal one for OR. Additional testing with the same subjects have shown wide visual attention for dyslexics and narrow one for OR, similar to previous results and analogous to the results on auditory perception above.
Overall, our data suggest a common perceptual strategy, which govern these sensory-modalities.
This PDF is available to Subscribers Only