Abstract

An attempt was made to explore the limitations in the influences of cognitive processes on perceptual processes as indicated by the probability and transfer effects in the stimulus probability paradigm. Three levels of visual similarity between the high probability stimulus and one of the low probability stimuli were manipulated to examine the processing stage at which the probability effects occur: The global configuration, relational features, and specific features. Three models, schema, cascade, and route-specific, were tested in terms of their predications about the transfer as well as the probability effects in various stimulus conditions. There were rather significant transfer effects at the feature similarity level, which was well below those levels reported by previous studies. This result was interpreted as supporting the !lotion that cognitive processes closely tied to stimulus probability affects the feature extraction stage, i.e.. the early part of the encoding stage in the processing of the stimulus. Patterns of mean RTs among stimulus probability conditions moderately supported the schema model.