An analysis of latencies and prediction in the fusional vergence system.

ABSTRACT The latency of the fusional vergence or the disparity vergence system has been found to vary from 130 to 250 milliseconds for unpredictable inputs. It has also been established that there is a prediction operator in the system which seems most effective around the 0.5 Hz region. The experiments also indicate a hitherto unnoticed difference between the convergence and the divergence latencies, with the latter being shorter. Similarities between the accommodation and the fusional vergence systems in terms of their latency and prediction characteristics are indicated by the results, but further work is necessary to test these correlations.