Abstract
This experiment was used to examine the process of visual integration using an uncertainty paradigm (Thomas & Olzak, 1996), in which observers' performance when they know the source of a cue is compared to performance when they do not have this information. Interpretations of results from this paradigm are used to determine how many sources of noise are present during a task. In the present study, observers' abilities to make judgments on a stimulus consisting of a sine wave grating surrounded by a similarly patterned annulus were examined. Data from these tasks were used to assess the contributions of either lateral inhibitory interaction or higher-level mechanisms that combine information over space. Results from the experiment were highly variable both within and between observers, and as such were inconclusive regarding the possible contributions of these mechanisms. However, significant asymmetries were found in the data; these asymmetries may be explained by varying cue salience or decision strategies. Additionally, observers in a related study were consistently poor at judging the location of the cue change, performing at a chance or near-chance level.
Supported by NIH grant EY13953 to LAO.