title: Visual search of expansion and contraction.
abstract: The perception of expansion/contraction in human subjects was examined with a visual search paradigm. When searching for a target defined by two-dimensional expansion among distractors defined by two-dimensional contraction, the time needed to find the target did not vary as the number of distractors was increased. However, for a target defined by two-dimensional contraction among distractors defined by two-dimensional expansion, the search time increased as a function of the number of distractors in the display. A similar search asymmetry remained between one-dimensional expansion and one-dimensional contraction, even though one-dimensional expansion was searched in a serial manner. This asymmetry between expansion and contraction reflects a basic characteristic of higher-order motion information processing.
authors.affiliation: Information Science Laboratory, NTT Basic Research Laboratories, Kanagawa, Japan. tatsuto@apollo3.BRL.ntt.co.jp
authors.forename: T
authors.initials: T
authors.lastname: Takeuchi
mesh_terms: D000328:Adult; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D009039:Motion Perception / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D011601:Psychophysics; D011930:Reaction Time