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Categorical perception of morphed objects using a free-naming experiment

Hartendorp, Mijke O.; Van der Stigchel, Stefan; Burnett, Hollie G.; Jellema, Tjeerd; Eilers, Paul H.C.; Postma, Albert


Mijke O. Hartendorp

Stefan Van der Stigchel

Hollie G. Burnett

Paul H.C. Eilers

Albert Postma


Morphed figures entail a dominant and nondominant interpretation. Testing perception of morphed objects using forced-choice methods demonstrates that morphed figures are perceived as their dominant interpretation ("categorical perception", or CP). Using a more natural free-naming response could reveal whether CP is an effect independent of method. In Experiment 1, therefore, series of morphed figures were tested for CP using free naming. Half of the morph series were identified as CP patterns. In Experiment 2, we used forced choice to investigate CP, resulting in an increase of number of CP series compared to free naming. The overlap between CP series of Experiments 1 and 2 was small, however. Experiment 3 revealed that higher perceptual similarity between the extremes of the series was strongly related to CP for the free-naming method, in contrast to the forced-choice method. We conclude that the observation of CP depends on the intactness of the intrinsic object structure caused by the morphing procedure.


Hartendorp, M. O., Van der Stigchel, S., Burnett, H. G., Jellema, T., Eilers, P. H., & Postma, A. (2010). Categorical perception of morphed objects using a free-naming experiment. Visual Cognition, 18(9), 1320-1347.

Journal Article Type Article
Acceptance Date Mar 1, 2010
Online Publication Date Jul 9, 2010
Publication Date Oct 15, 2010
Print ISSN 1350-6285
Electronic ISSN 1464-0716
Publisher Taylor and Francis
Peer Reviewed Peer Reviewed
Volume 18
Issue 9
Article Number PII 924179568
Pages 1320-1347
Keywords Object categorization; Categorical perception; Free naming
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