June 2007
Volume 7, Issue 9
Free
Vision Sciences Society Annual Meeting Abstract  |   June 2007
Effects of experience and task type on unsupervised categorization of novel, 3D objects
Author Affiliations
  • Theresa Cooke
    Department of Cognitive and Computational Psychophysics, Max Planck Institute for Biological Cybernetics
  • Christian Wallraven
    Department of Cognitive and Computational Psychophysics, Max Planck Institute for Biological Cybernetics
  • Heinrich Buelthoff
    Department of Cognitive and Computational Psychophysics, Max Planck Institute for Biological Cybernetics
Journal of Vision June 2007, Vol.7, 464. doi:10.1167/7.9.464
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Theresa Cooke, Christian Wallraven, Heinrich Buelthoff; Effects of experience and task type on unsupervised categorization of novel, 3D objects. Journal of Vision 2007;7(9):464. doi: 10.1167/7.9.464.

      Download citation file:


      © 2016 Association for Research in Vision and Ophthalmology.

      ×
  • Supplements
Abstract

Rosch et al. (1976) and others have argued that the shape of objects is a fundamental determinant of category structure. In a previous study, we observed that after ten hours of visual exposure to a series of novel, 3D objects, subjects asked to perform free categorization in a sequential presentation task did so primarily on the basis of shape differences (6/10) as opposed to texture (1/10) or a combination of both (3/10) (weight of texture relative to shape: M=26%, SE=10%). In contrast, no such effect was found after ten hours of haptic exposure, i.e., shape and texture were equally weighted (M=55%, SE=8%). We hypothesized that, prior to experience, subjects are equally likely to use any weighting strategy, but that lengthy visual experience makes shape-dominated groupings more likely. Thus, in Experiment 1, subjects categorized objects either without any prior experience or after 1h of similarity judgments. Mean shape/texture weight was not significantly different from 50% in either condition, a result in agreement with our hypothesis. In Experiment 2, we tested whether the same pattern would hold for two different types of categorization tasks. In the first task, 10 naïve subjects viewed all objects simultaneously and sorted them into any number of groups. In the second task, 10 naïve subjects were sequentially shown two pairs, each consisting of the target and one of two category prototypes, and indicated which pair of objects was drawn from the same group. Contrary to our expectation, subjects in the array task relied on texture differences (M=80%, SE=7%), while subjects in the pair task relied more on shape (M=32%, SE=3%). These results demonstrate that shape differences do not always act as the key determinants of category structure; the sensory modality used to experience objects, the length of exposure, as well as task parameters also play a role.

Cooke, T. Wallraven, C. Buelthoff, H. (2007). Effects of experience and task type on unsupervised categorization of novel, 3D objects [Abstract]. Journal of Vision, 7(9):464, 464a, http://journalofvision.org/7/9/464/, doi:10.1167/7.9.464.
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×