TY - JOUR
T1 - Tactile perception in developmental dyslexia
T2 - A psychophysical study using gratings
AU - Grant, Arthur C.
AU - Zangaladze, Andro
AU - Thiagarajah, Mahesh C.
AU - Sathian, K.
N1 - Funding Information:
We are grateful to our subjects for volunteering. We are indebted to Dr Deborah Hyde of the Emory Disabilities Office, Dr Martha Burdette and Dr Wood Smethurst of Ben Franklin Academy, and Pam Helms of the Howard School (all in Atlanta, GA) for help with recruiting subjects. We thank Gad Geiger of the Research Laboratory of Electronics, Massachusetts Institute of Technology, Boston, MA, for allowing us to test some of his subjects and Dr David Friedes, Department of Psychology, Emory University for helpful comments on identification of dyslexic individuals. We also acknowledge the helpful suggestions of anonymous reviewers of this manuscript. This work was supported in part by grants to KS from the Orton Dyslexia Society and the NINDS.
PY - 1999/9
Y1 - 1999/9
N2 - Multiple sensory abnormalities have been reported in individuals with developmental dyslexia, especially in the visual and auditory systems. We used gratings of alternating ridges and grooves to investigate tactile perception in this disorder using two tasks: spatial acuity-dependent discrimination of grating orientation and discrimination of gratings varying in ridge width. Compared to age-matched normal subjects, dyslexics were significantly impaired on grating orientation discrimination, with mean thresholds that were nearly twice normal. Unlike normal subjects, their performance on this task was slightly but significantly worse on the dominant hand than on the non-dominant hand. Dyslexics also showed a substantial but non-significant trend for impairment on grating ridge width discrimination. A group of subjects with attention deficit disorder did not differ significantly from normal on any of these measures. These findings expand the range of perceptual deficits reported in developmental dyslexia. Possible explanations for the results, including difficulties with temporal processing, abnormal lateral masking or parietal lobe dysfunction are discussed. Copyright (C) 1999 Elsevier Science Ltd.
AB - Multiple sensory abnormalities have been reported in individuals with developmental dyslexia, especially in the visual and auditory systems. We used gratings of alternating ridges and grooves to investigate tactile perception in this disorder using two tasks: spatial acuity-dependent discrimination of grating orientation and discrimination of gratings varying in ridge width. Compared to age-matched normal subjects, dyslexics were significantly impaired on grating orientation discrimination, with mean thresholds that were nearly twice normal. Unlike normal subjects, their performance on this task was slightly but significantly worse on the dominant hand than on the non-dominant hand. Dyslexics also showed a substantial but non-significant trend for impairment on grating ridge width discrimination. A group of subjects with attention deficit disorder did not differ significantly from normal on any of these measures. These findings expand the range of perceptual deficits reported in developmental dyslexia. Possible explanations for the results, including difficulties with temporal processing, abnormal lateral masking or parietal lobe dysfunction are discussed. Copyright (C) 1999 Elsevier Science Ltd.
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U2 - 10.1016/S0028-3932(99)00013-5
DO - 10.1016/S0028-3932(99)00013-5
M3 - Article
C2 - 10509841
AN - SCOPUS:0032767603
SN - 0028-3932
VL - 37
SP - 1201
EP - 1211
JO - Neuropsychologia
JF - Neuropsychologia
IS - 10
ER -