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Updated: Feb 16, 2026
Analysis and Specification of Starch Granule Size Distributions
Published on: March 4, 2021
Tool use produces a size illusion revealing action-specific perceptual mechanisms
Jihyun Suh1, Richard A Abrams1
1Department of Psychological and Brain Sciences, Washington University in St. Louis, United States.
Abstract:
In four experiments, participants estimated the sizes of target objects that were either out of reach, or that could be reached by a tool (a stylus or laser pointer). Objects reachable with the aid of a tool were perceived to be smaller than identical objects without a tool. Participants' responses to questioning rule out demand characteristics as an explanation. This new size illusion may reflect a direct impact of tool use on perceived size, or it may stem from the effects of tool use on perceived distance. Both possibilities support action specific accounts of perception.
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