Dynamic interactions between accommodation and convergence

Frequency-domain equations are derived for the current dual-interaction model of accommodation and convergence control, and its adaptive behavior is related to the system´s parameters. Contrary to predictions based on the steady-state performance of the model, dynamic analysis shows that the AC/A is sensitive to the method of measurement, and a procedure is established for its reliable determination. The results provide theoretical support for the empirical finding that low AC/A and CA/C ratios are associated with high accommodative and convergence adaption, respectively. The derived equations should help future studies relate the physiological behavior of accommodative and convergence to specific model parameters.