Changes in length judgments caused by rotation of the contextual distractor

• Published in: Attention, perception & psychophysics Vol. 85; no. 1; pp. 196 - 208
• Main Authors: Bulatov, Aleksandr, Bulatova, Natalija, Diržius, Edgaras, Mickienė, Lina
• Format: Journal Article
• Language: English
• Published: New York Springer US 2023; Springer Nature B.V
• Subjects: Behavioral Science and Psychology; Cognitive Psychology; Experiments; Humans; Hypotheses; Judgment; Localization; Optical Illusions; Photic Stimulation - methods; Psychology; Psychophysics - methods; Rotation; Stimuli; Perceptual positional shift; Distractor rotation; Length illusion; Spatial summation
• ISSN: 1943-3921; 1943-393X
• DOI: 10.3758/s13414-022-02596-y

In the present study, we tested the applicability of the computational model of the illusion of interrupted spatial extent (Bulatov, Marma, & Bulatova, Attention, Perception, & Psychophysics , 82, 2714−2727, 2020) to account for the psychophysical data collected with three-dot stimuli containing a cross-shaped contextual distractor. In different series of experiments, the illusion magnitude changes caused by the rotation of distractors with different values of the internal angle (45°, 75°, and 90°) were quantitatively determined. It was shown that the data obtained for all modifications of stimuli can be rather well approximated by model functions proportional to the sum of the absolute values of cosines. A good agreement between theoretical calculations and experimental results supports the suggestion that the perceptual displacement of the stimulus terminators, which occurs due to the processes of local integration of neural activity, may be one of the main causes of the illusion investigated.