CONTOUR INTEGRATION IN STRABISMIC AMBLYOPIA - THE SUFFICIENCY OF AN EXPLANATION-BASED ON POSITIONAL UNCERTAINTY

Contour integration was measured in a group of strabismic amblyopes to determine if an explanation based solely on positional uncertainty wa s sufficient to explain performance, The task involved the detection o f paths composed of micropatterns with correlated carrier orientations embedded in a field of similar micropatterns of random position and o rientation (Field ct al. Contour integration by the human visual syste m; Evidence for a local ''association field'', Vision Research, 33, 17 3-193, 1993), The intrinsic positional uncertainty for each amblyopic eye was measured with the same stimulus and it was found that in 10 ou t of our 11 amblyopic subjects, the reduced performance of the amblyop ic eye could be modelled by the normal eye with an equivalent amount o f positional uncertainty added to the stimulus, We conclude that the r ules by which cellular outputs are combined, at least as reflected by this task, are normal in amblyopia. (C) 1997 Elsevier Science Ltd.