This research concerns ways in which experience fine-tunes perception. Examples are the practiced worker's ability to detect subtle flaws in a product, or a person's ability to identify quickly a familiar face in a crowd. The research will follow two lines. The first concerns a relatively short-term effect called priming, seen when advance information about a stimulus leads to its more efficient detection. Experiments will determine the precise nature of such perceptual changes and will address the manner in which primed expectancies are learned. A second line of research concerns more permanent perceptual learning. Experiments will investigate what changes in perception occur with practice, how changes in one task may affect performance on others, and the possibility that perceptual learning involves costs as well as benefits. In order to study such learning it is necessary to control the subject's visual experience. The Bloughs' experiments use pigeons, whose excellent vision is well understood; pigeons and primates, including humans, process visual information in many similar ways. This work is unique in its focus on relations between perception and learning. The use of relatively simple stimuli combined with the tools of psychophysical anslysis will permit the Bloughs to distinguish among stimulus-based variables and several classes of experiential factors as determiners of what is seen.
