Visual-ocular control of normal and learning-disabled children.
Much of the data typically presented to support the vestibular dysfunction hypothesis among learning-disabled children is based on a measure of vestibular function that is confounded by visual input. Thus these data may provide evidence of deficits in visual-ocular function in this population. To explore this possibility the authors investigated the differences in visual-ocular function, in particular optokinetic nystagmus (OKN), between normal and learning-disabled children. Children were tested for refixation saccades, smooth ocular pursuit, spontaneous nystagmus, gaze nystagmus and OKN. The testers were blind to the group to which the children belonged. No significant differences were found between the groups on any of the variables. It is concluded that there is no difference in nystagmic behaviour between normal and learning-disabled children, and that the differences in eye movements reported among learning-disabled children should not be attributed to the visual-ocular control functions investigated here.
Polatajko
H J
HJ
Department of Occupational Therapy, University of Western Ontario, Faculty of Applied Health Sciences, London, Canada.
D002648:Child; D005133:Eye Movements; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007859:Learning Disabilities / Q000503:physiopathology*; D008297:Male; D009801:Oculomotor Muscles / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*; D011698:Pursuit, Smooth; D012438:Saccades