Automaticity in fusional vergence therapy

Fusional vergence therapy is typically performed under conditions that permit the patient to direct considerable attention and effort to the visual task. Unless visual function is sufficiently automatic as to require minimal attention and effort, attention directed toward visual function may detract from that available for cognitive processing. This report describes a method to develop greater automaticity of fusional vengence through the use of concurrent demands.

A retrospective pilot study of patient records was performed to assess the use of a concurrent motor demand (bouncing on a rebounder) to develop automaticity of fusional vergence.

In most cases, patients who achieved adequate fusional vergence without the concurrent motor demand demonstrated a decrease in fusional vergence ranges when the motor demand was added, and then improved with practice so that vergence ranges while bouncing on the rebounder approached those achieved while seated. This pattern was obtained in 75 percent of the base-out and 57.1 percent of the base-in protocols. Some patients who showed a decrement in performance with introduction of the concurrent demand failed to improve with practice; this pattern was observed in 28.6 percent of the base-in protocols, but in none of the base-out protocols. Some patients showed no decrease in performance when the concurrent distracting task was introduced (observed in 25 percent of the base-out protocols and 14.3 percent of the base-in protocols).

In most cases, maximum automaticity is not achieved when fusional vergence is trained under conditions that permit the patient to devote full attention to the vergence task. Introducing concurrent distractors may be desirable to automate performance and enable the patient to maintain fusional vergence even while attention is directed to the concurrent task. Heightened automaticity may reduce the effort and attention that must be directed toward binocular function, and hence maximize attentional capacity available for information-processing, comprehension, and performance on the task at hand.