Binocular Integration of Perceptually Suppressed Visual Information in Amblyopia

Abstract

Purpose The purpose of this study was to assess whether motion information from suppressed amblyopic eyes can influence visual perception. Methods Participants with normal vision ( n = 20) and with amblyopia ( n = 20; 11 anisometropic and 9 strabismic/mixed) viewed dichoptic, orthogonal drifting gratings through a mirror stereoscope. Participants continuously reported form and motion percepts as gratings rivaled for 60 seconds. Responses were binned into categories ranging from binocular integration to complete suppression. Periods when the grating presented to the nondominant/amblyopic eye was suppressed were analyzed further to determine the extent of binocular integration of motion. Results Individuals with amblyopia experienced longer periods of non-preferred eye suppression than controls. When the non-preferred eye grating was suppressed, binocular integration of motion occurred 48.1 ± 6.2% and 31.2 ± 5.8% of the time in control and amblyopic participants, respectively. Periods of motion integration from the suppressed eye were significantly non-zero for both groups. Conclusions Visual information seen only by a suppressed amblyopic eye can be binocularly integrated and influence the overall visual percept. These findings reveal that visual information subjected to interocular suppression can still contribute to binocular vision and suggest the use of appropriate optical correction for the amblyopic eye to improve image quality for binocular combination.

Current Developments in the Management of Amblyopia with the Use of Perceptual Learning Techniques

“…Studies show that patients thought to be treated effectively, achieving normal VA, still exhibit significant impairment in contrast sensitivity and stereoacuity [62]. As already mentioned, the visual information from the amblyopic eye, though being suppressed, is still available for visual processing, contributing to binocular vision [18]. These observations suggest that amblyopia treatment should address the binocular dysfunction [13].…”

“…Suppression is marked across the whole amblyopic visual field, but it is stronger in the foveal region, creating a distinct functionally blind area called suppression scotoma [14,18,19]. Luminance and contrast sensitivity thresholds are elevated within that area, form and motion information are suppressed, and objects presented within the scotoma do not become consciously aware [14,18,19]. Recent studies show that the information from the amblyopic eye, though strongly suppressed from conscious perception, still remains available for binocular processing [18].…”

“…Luminance and contrast sensitivity thresholds are elevated within that area, form and motion information are suppressed, and objects presented within the scotoma do not become consciously aware [14,18,19]. Recent studies show that the information from the amblyopic eye, though strongly suppressed from conscious perception, still remains available for binocular processing [18].…”

Suppression in Amblyopia - Cause or Consequence?

“…But recent studies showed that visual information seen by the amblyopic eye, which is under suppression, can be binocularly integrated and influence the overall visual percept. According to the authors, visual information subjected to interocular suppression can still contribute to binocular vision and suggest an appropriate optical correction for the amblyopic eye to improve image quality for the binocular combination [37]. It means that suppressed visual information continues to be represented within the brain even when it is blocked by chronic pathological suppression.…”

Comparison of compliance among patients with pediatric amblyopia undergoing virtual reality-based and traditional patching method training

“…Amblyopia is a common eye disease in children associated with impairments in processing tactile, motion, and visual stimuli, resulting in abnormal visual development, low visual acuity, and binocular diplopia (1)(2)(3). Amblyopia was once considered a monocular disease; however, a growing body of evidence suggests the involvement of structural and functional abnormalities in both eyes (4). Pediatric amblyopia is associated with high financial and psychological burden to both children and parents.…”