Abstract
To fuse an autostereogram, the intersection of the viewer’s visual axes must occur in front of or behind the plane of the physical stereogram to attain the vergence angle necessary to place the left and right images on corresponding areas of the two retinas. Accommodation, however, should remain in the plane of the physical autostereogram for clearest perception of the disparity-defined form. The direction of decoupling of accommodation and convergence needed for autostereogram fusion is in the direction opposite that typically found with observers under normal viewing conditions. Our previous work compared common clinical indicators of vergence ability with subjects’ self-reported and measured autostereogram skills and found significant differences between those with poor versus good self-reported and measured autostereogram skill for vergence facility, near phoria, and TNO stereoacuity. The present study was undertaken to compare clinical indicators of accommodative function to self-rated and measured autostereogram skills. Our results show that subjects whose self-rated autosterogram skills were "poor" did not demonstrate statistically significantly poorer performance on any of the clinical tests of accommodative function. Subjects whose measured autostereogram skills were "poor" demonstrated statistically significantly poorer performance compared to subjects with "excellent" measured autostereogram skills only on amplitude-adjusted accommodative facility; however, the differences were not clinically significant. A statistically and clinically significant difference in symptom scores on the CISS manifested between the groups who self-rated "poor" versus "excellent" on autostereogram skills, but not between the groups who measured "poor" versus "excellent" on autostereogram skills. These results suggest that difficulty with fusing autostereograms is not likely due to an underlying accommodative dysfunction.
Meeting abstract presented at VSS 2012