LASCER Bode plots for normal, amblyopic, and stereoanomalous observers

Indices of laterality, interocular response latency difference, and binocular summation derived from Bode plots (amplitude-versus-temporal frequency and phase lag-versus-temporal frequency) of cortical responses evoked by laser speckle (LASCER) are correlated with common tests used in clinical refraction. We evaluated eight normal observers and eleven observers with histories of amblyopia and/or stereoanomalies. We find that: (1) LASCER amplitude is reduced in the amblyopic eyes relative to the unaffected fellow eyes, (2) LASCER response latency is increased in the amblyopic eyes relative to the unaffected fellow eyes, and (3) binocular LASCER summation is reduced in stereoanomalous observers. The phenomenal appearance of laser speckle is different for amblyopic eyes than unaffected fellow eyes. Neural disturbances in pattern perception may account for these results.