Dichoptic and physical information combination: a comparison.

Two experiments, in which information from two different kinds of degraded (low-pass filtered and regionally averaged or blocked) visual stimuli (aircraft silhouettes) was combined, are reported. In the first experiment, the degraded images were perceptually combined by being separately presented to each eye in a dichoptic viewing situation. Both stimuli in both presentations were masked by identical random visual interference. When the two stimuli were visually fused, performance in a discrimination task was enhanced over that in control situations in which only one of the two stimuli was presented. In the second experiment the two degraded stimuli were physically superimposed prior to binocular presentation, with a similar result. The results of this hybrid (masking/binocular summation) experiment suggest that true advantageous information pooling occurs when these two types of degraded stimuli are combined either physically or dichoptically.