Translating From Perceptual to Cognitive Coding

Translating From Perceptual to Cognitive Coding Tyler Davis (thdavis@mail.utexas.edu) Bradley C. Love (brad_love@mail.utexas.edu) W. Todd Maddox (maddox@psy.utexas.edu) Department of Psychology, The University of Texas at Austin Austin, TX 78712 USA features typical to a certain class of objects or a particular individual (Gauthier & Tarr, 1997; Tanaka & Gauthier, 1997). While these representational changes have been shown to facilitate the learning of new similar classes or new individuals within a class (Gauthier, et al., 1998; Tanaka, Curran, & Sheinberg, 2005), they likely do not generalize beyond a given basic level category. Thus, perceptual expertise is extremely useful for developing an automatic, stable, and permanent reidentification capacity for a class or an individual object, but it is too slow and specific to subserve all of the occasions where people need to be able to engage in subordinate level identification. Another capacity, which may bootstrap reidentification performance while perceptual expertise is developing, is a process we will refer to as translation. Translation will be defined as the mapping of sensory information onto a compositional alphabet of symbols that refer to sensory qualities or featural characteristics of objects. As with perceptual expertise, we argue that many of these symbols are learned, but instead of being fused configural entities, they refer to independent features, and can be applied across a wider variety of domains. These symbols may be acquired from a variety of sources, most particularly through the learning of a language (e.g. Quine, 1960), explicit instruction (Experiment 2), or the learning of task specific invariants (e.g Schyns, Goldstone, & Thiabut, 1998). For these symbols to be useful for object reidentification, a person must be able to use them systematically, and productively. That is, if an individual possesses a set of feature labels that they are able to attach to one object, they should at the very least be able to identify those qualities in any of their combinations in any other object. Another further constraint on the success of translation in a given context is that the symbols must stand in a one to one relationship with the sensory qualities to which they refer. For example, the term green may be sufficient for identifying a particular object when the only colors in the environment are green or blue, but when the colors of the objects vary more continuously the term green will quickly lose its utility. Though we are treating translation and the development of expertise as distinct, in many cases they may be intertwined in a manner similar to the algorithmic and automatic processes that operate in tasks like mental math (e.g. Logan, 1988; see Figure 1 for summary of proposed pathways). To this end, translation may not only be well suited for bootstrapping reidentification during the early stages of perceptual expertise, but it might continue to operate Abstract An important question in cognitive science is how conceptual knowledge interacts with perception. For example, how does knowing that trucks have wheels and windshields impact a person's recognition of a truck? Through a series of categorization tasks, we explore two pathways by which humans can learn to identify objects. One pathway involves the acquisition of perceptual expertise through extensive task- relevant experience, and leads to the rapid identification of individual stimuli. A second pathway involves a translation process in which percepts of objects are encoded into symbolic descriptions. The use of this pathway results in a similar ability to identify individual stimuli, but requires more time to operate due to the demands of the online translation process. These results are discussed in terms of related work in categorization, perceptual expertise, and influence of language on thought. Keywords: expertise; object identification; symbolic coding; translation; categorization; language and thought Introduction One of the most fundamental psychological capacities is the ability to recognize sameness. In categorization and object recognition this capacity is typically studied in terms of the formation and use of equivalence classes, however there are numerous occasions where a person’s goals require going beyond category membership to the level of individual identity. Whether it be taking the right car home from work, or the right dog home from the dog park, many times getting things exact makes all of the difference. This ability to recognize that something is the same as or equivalent to something seen on a previous occasion, termed reidentification (cf. Millikan, 1998), is fundamental to our everyday survival. The present study investigates two capacities, perceptual expertise and translation that interact to allow humans to maximize their ability to track objects across time. Perceptual expertise refers to a variety of representational changes that occur due to experience with a particular object or within a particular domain. These changes alter the way in which people process the objects for which they have expertise such that they become as efficient at recognizing them and as knowledgeable about their unique characteristics at subordinate levels (e.g. as an individual or a species) as they are at naming and discussing them as members of a basic level category (Tanaka & Taylor, 1991). However, perceptual expertise is acquired rather slowly, with the representations formed being largely configural, and thus specific to the metric relationships between