English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Poster

Interdependence of feature dimensions in the representation of 3D objects

MPS-Authors
/persons/resource/persons83897

Edelman,  S
Department Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Max Planck Society;
Max Planck Institute for Biological Cybernetics, Max Planck Society;

/persons/resource/persons83839

Bülthoff,  HH
Department Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Max Planck Society;
Max Planck Institute for Biological Cybernetics, Max Planck Society;

/persons/resource/persons83840

Bülthoff,  I
Department Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Max Planck Society;
Max Planck Institute for Biological Cybernetics, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Edelman, S., Bülthoff, H., & Bülthoff, I. (1996). Interdependence of feature dimensions in the representation of 3D objects. Poster presented at Annual Meeting of the Association for Research in Vision and Ophthalmology (ARVO 1996), Fort Lauderdale, FL, USA.


Cite as: https://hdl.handle.net/11858/00-001M-0000-0013-EB96-0
Abstract
Purpose. The dimensions of the representation space of 3D objects may be independent, if nonaccidental - generic or qualitative shape contrasts serve as the distinguishing features. Alternatively, the dimensions can be interdependent, as predicted by some theories that postulate metric feature-space representations. To explore this issue, we studied human performance in forced-choice classification of objects composed of 4 geon-like parts, emanating from a common center. Methods. The two class prototypes were distinguished by qualitative contrasts (cross-section shape; bulge/waist), and by metric parameters (degree of bulge/waist, taper ratio). Subjects were trained to discriminate between the two prototypes (shown briefly, from a number of viewpoints, in stereo) in a 1-interval forced-choice task, until they reached a 90% correct-response performance level. Subsequent trials involved both original and modified versions of the prototypes; the latter were obtained by varying the metric parameters both orthogonally (ORTHO) and in parallel (PARA) to the line connecting the prototypes in the parameter space. Results. 8 out of 11 subjects succeeded to learn the task within the allotted time. For these subjects, the error rates increased progressively with the parameter-space displacement between the stimulus and the corresponding prototype. The effect of ORTHO displacement was significant: F(1, 68) = 3.6, p < 0.06. There was also a hint of a marginal PARA displacement effect: F(1, 68) = 1.9, p = 0.17 Conclusions. Theories that postulate exclusive reliance on qualitative contrasts (such as Biederman's Recognition By Components) predict near-perfect discrimination performance for stimuli derived from the prototypes both by PARA and by ORTHO parameter-space displacement. Our results contradict this prediction, and support the notion of a metric representation space, in which any displacement away from the familiar region incurs performance costs.