Accommodative responses stimulated from the Maddox components of vergence in participants with normal binocular...

Understanding the interplay of responses to stimulated accommodative blur (B), disparity (D), proximal (P), and diminished blur (-b), disparity (-d), and proximal (-p) cueing within binocularly normal participants is important for comparisons to patient populations. Recordings from 31 participants enrolled in the Convergence Insufficiency Neuro-mechanism Adult Population Study (NCT03593031) were collected. After artifact removal, analyses were performed on 20 BDP, 22 BD(-p), 27 BP(-d), 29 DP(-b), 24 B(-dp), 31 D(-bp), and 29 P(-bd) participant-level response datasets. Group-level statistics were assessed to evaluate the main effect of cue conditions on peak velocity (diopters/second) and final amplitude (diopters). Peak velocity assesses the preprogrammed portion of accommodation, whereas final amplitude assesses the feedback portion of accommodation. Post hoc pairwise comparisons were used to determine cue-to-cue significance. Significant main effects were found for final amplitude and peak velocity metrics (p < 0.05), indicating differences across cue conditions. Responses evoked by blur and disparity were comparable to those responses with all cues (BDP) for both far-to-near and near-to-far transitions. Responses evoked by blur or disparity cues elicited a reduced accommodative response, as indicated by peak velocity and final amplitude, compared to responses from blur and disparity cues. Blur and disparity cues can stimulate accommodative responses through the convergence accommodative/convergence crosslink. Results support significant contributions from blur and disparity cueing to accommodative responses compared with the proximal cue. This research forms the foundation for comparing accommodative responses in individuals with binocular vision dysfunctions.