POSITIONAL LOSS IN STRABISMIC AMBLYOPIA - INTERRELATIONSHIP OF ALIGNMENT THRESHOLD, BIAS, SPATIAL SCALE AND ECCENTRICITY

In order to understand the spatial loss in strabismic amblyopia and it s relationship to the contrast sensitivity deficit, we measured alignm ent performance for a three element vertical alignment task in which t he elements were equi-visible, spatial Gabors. We derived the threshol d and bias and compared these for stimuli of different spatial scale a nd eccentricity. Our results suggest that: (1) the deficits for alignm ent thresholds and bias are uncorrelated; (2) in the majority of strab ismic amblyopes, both deficits are scale invariant; (3) the form of th e regional distribution depends on the spatial measure used and the sc ale at which it is measured; and (4) there is a poor correlation betwe en the deficit for either spatial measure and the contrast sensitivity loss. Copyright (C) 1996 Elsevier Science Ltd.