Orientation variance discrimination in amblyopia.

Our previous results showed that while amblyopes can efficiently integrate visual signals, they are poor at segregating signals in noise. This could be either because integration detectors have broader bandwidths or because of a selective extrastriate segregation anomaly. One consequence of the former would be poorer variance discrimination. Using a two-alternative forced-choice paradigm, observers were asked to judge the orientational variance for arrays of 16 Gabors. All observers, be they normal or amblyopic, could perform the task similarly, although at high spatial frequencies, amblyopic eyes needed slightly more incremental variance than the normal eyes. We conclude that normals and amblyopes integrate signals in a similar way.