Can Perceptual Learning Help the Learning of Multiple Family Resemblance Categories?

Researchers are interested in how humans and animals learn perceptual categories. Prior research has suggested that there is one system for category learning (e.g., Bruner et al., 1956; Hull, 1920), but recent research suggests there are multiple systems (e.g., Ashby & Maddox, 2005). Previous research shows that single-family resemblance categories can be learned through exposure and can be generalized to novel stimuli (Reed et al., 1999). One multiple systems theory, COVIS, predicts this ability is due to simple fluency (Ashby & Maddox, 2005). However, representational theories of perceptual learning, suggest that the learning reflects different parts of the stimulus are being unitized (Goldstone, 1999). If category learning from mere exposure reflects fluency, exposure should only aid learning in a single category task. If it reflects unitization, multiple category learning should be possible from exposure. We are testing to see if people can simultaneously learn two categories through mere exposure and generalize to novel stimuli. This study aims to investigate how mechanisms of perceptual learning may facilitate category learning. People completed a relevant and irrelevant task, each of which have an exposure and a test phase. During the exposure phases, two prototypes are created as well as different distortions levels of the prototypes. The participants were presented with level 3, 5, and 7 distortions (lower distortions are more similar to the prototype). The participant was asked if they would remember the shape if they saw it tomorrow. During the relevant test, the same two prototypes from the exposure phase were used to create Category A and B members. During the irrelevant test, two new prototypes were used to create category members. Therefore, what the participants were exposed to is irrelevant to the test phase. The participants were presented with Category A and B members as well as random shapes and asked if the shape was part of the A or B category or neither. Preliminary data suggests participants perform better in the categorization task after receiving relevant exposure. This suggests that people can learn two different categories and generalize to novel stimuli after mere exposure.