title: Impact of stimulus uncanniness on speeded response.
abstract: In the uncanny valley phenomenon, the causes of the feeling of uncanniness as well as the impact of the uncanniness on behavioral performances still remain open. The present study investigated the behavioral effects of stimulus uncanniness, particularly with respect to speeded response. Pictures of fish were used as visual stimuli. Participants engaged in direction discrimination, spatial cueing, and dot-probe tasks. The results showed that pictures rated as strongly uncanny delayed speeded response in the discrimination of the direction of the fish. In the cueing experiment, where a fish served as a task-irrelevant and unpredictable cue for a peripheral target, we again observed that the detection of a target was slowed when the cue was an uncanny fish. Conversely, the dot-probe task suggested that uncanny fish, unlike threatening stimulus, did not capture visual spatial attention. These results suggested that stimulus uncanniness resulted in the delayed response, and importantly this modulation was not mediated by the feelings of threat.
authors.affiliation: Research Center for Advanced Science and Technology, The University of Tokyo Tokyo, Japan.
authors.forename: Kohske
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Core Research for Evolutional Science and Technology, Japan Science and Technology Agency Tokyo, Japan ; Graduate School of Arts and Sciences, The University of Tokyo Tokyo, Japan.
authors.forename: Haruaki
authors.initials: H
authors.lastname: Fukuda
authors.affiliation: Brain Science Institute, Tamagawa University Tokyo, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Samejima
authors.affiliation: Research Center for Advanced Science and Technology, The University of Tokyo Tokyo, Japan ; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency Tokyo, Japan ; Faculty of Science and Engineering, Waseda University Tokyo, Japan.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Core Research for Evolutional Science and Technology, Japan Science and Technology Agency Tokyo, Japan ; Graduate School of Arts and Sciences, The University of Tokyo Tokyo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ueda
keywords: Uncanny; direction discrimination; dot-probe; reaction Time; spatial cueing; speeded response; uncanny valley