Hiroyuki Ito - Academia.edu (original) (raw)

Papers by Hiroyuki Ito

Research paper thumbnail of Audiovisual Integration: An Investigation of the ‘Streaming-bouncing’ Phenomenon

Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science, 2004

Temporal aspects of the perceptual integration of audiovisual information were investigated by ut... more Temporal aspects of the perceptual integration of audiovisual information were investigated by utilizing the visual 'streaming-bouncing' phenomenon. When two identical visual objects move towards each other, coincide, and then move away from each other, the objects can either be seen as streaming past one another or bouncing off each other. Although the streaming percept is dominant, the bouncing percept can be induced by presenting an auditory stimulus during the visual coincidence of the moving objects. Here we show that the bounce-inducing effect of the auditory stimulus is paramount when its onset and offset occur in temporal proximity of the onset and offset of the period of visual coincidence of the moving objects. When the duration of the auditory stimulus exceeded this period, visual bouncing disappears. Implications for a temporal window of audiovisual integration and the design of effective audiovisual warning signals are discussed.

Research paper thumbnail of The object and background hypothesis for vection

Vision Research, 2009

Stimulus attributes effective in inducing vection can be generalized by the object and background... more Stimulus attributes effective in inducing vection can be generalized by the object and background hypothesis, that is, properties that belong to 'objects' weaken vection while those of the 'background' enhance vection. We presented a motion-defined Rubin's vase to induce vection. Results clearly indicated that the background dominantly induced vection. We further demonstrated that motion stimuli that had a property of an object could not induce vection efficiently. Investigating vection in the framework of the object and background hypothesis provides a unified point of view for understanding vection stimuli.

Research paper thumbnail of Background stripes affect apparent speed of rotation

Journal of Vision, 2005

Introduction We have found that, when a line rotates at constant speed about its own center again... more Introduction We have found that, when a line rotates at constant speed about its own center against a background of stationary vertical stripes, it appears to vary in speed during each revolution, looking markedly faster when it passes through the vertical (figure 1a). Background stripes affect apparent speed of rotation

Research paper thumbnail of Inhibition of vection by red

Attention, Perception, & Psychophysics, 2010

We investigated the effects of colors on vection induction. Expanding optical flows during one's ... more We investigated the effects of colors on vection induction. Expanding optical flows during one's forward d self-motion were simulated by moving dots. The dots and the background were painted in equiluminant red and green. Experiments 1 and 2 showed that vection was weaker when the background was red than when the background was green. In addition, Experiment d 3 showed that vection was weaker when the moving dots were red than when the dots were green. Experiment k 4 demonstrated that red dots on a red background induced very weak vection, as compared with green dots on a green background. In Experiments 5 and 6, we showed that the present results could not be explained by a luminance artifact. Furthermore, Experiment d 7 showed that a moving red grating induced weaker vection than did a green one. We concluded that a red visual stimulus inhibits vection.

Research paper thumbnail of Effect of surrounding texture on the pursuit-pursuing illusion

i-Perception, 2014

The pursuit-pursuing illusion is a visual illusion where a circular object placed in the centre o... more The pursuit-pursuing illusion is a visual illusion where a circular object placed in the centre of a radial pattern consisting of thin sectors is seen to move in the pursuit eye movement direction. The present study investigates the role of the surrounding texture, replacing the sectors with random dots or stripes in an orientation that was orthogonal, parallel or oblique to the pursuit direction. The experiments demonstrate that the acquired illusory effect was large for the orthogonal stripes. However, each surrounding texture produces a relatively smaller effect than the radial sectors. These results suggest that a hypothesis based on the property of a centre-surround relative-motion detector cannot fully explain the illusion and that the radial stimulus structure itself plays an important role in this illusion.

Research paper thumbnail of Illusory depth perception of oblique lines produced by overlaid vertical disparity

Vision Research, 2005

Our visual system matches images from both eyes to establish a single view and stereo depth even ... more Our visual system matches images from both eyes to establish a single view and stereo depth even when they contain a certain amount of vertical disparity. This paper demonstrates a new stereo effect showing an aspect of vertical disparity processing. When oblique lines without disparity are overlaid with sparse random dots with vertical disparity, the lines look closer or farther in depth. The characteristics of this stereo illusion were experimentally investigated. The results showed that the sign of the perceived depth of the oblique lines depended on the combination of the line orientation and the vertical disparity sign, and that the amount of perceived depth became larger as the line orientation became more horizontal. The depth illusion robustly existed even under conditions that ruled out eye movements (i.e., vertical vergence and cyclovergence) by local-parallel or brief presentations of the stereo figures. This phenomenon suggests that the visual system locally measures vertical disparity and is not simply tolerating a small amount of vertical disparity. Stereo capture of vertical disparity and horizontal matching after vertical image shifts were proposed as possible explanations for the depth illusion.

Research paper thumbnail of Audiovisual Integration: An Investigation of the ‘Streaming-bouncing’ Phenomenon

Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science, 2004

Temporal aspects of the perceptual integration of audiovisual information were investigated by ut... more Temporal aspects of the perceptual integration of audiovisual information were investigated by utilizing the visual 'streaming-bouncing' phenomenon. When two identical visual objects move towards each other, coincide, and then move away from each other, the objects can either be seen as streaming past one another or bouncing off each other. Although the streaming percept is dominant, the bouncing percept can be induced by presenting an auditory stimulus during the visual coincidence of the moving objects. Here we show that the bounce-inducing effect of the auditory stimulus is paramount when its onset and offset occur in temporal proximity of the onset and offset of the period of visual coincidence of the moving objects. When the duration of the auditory stimulus exceeded this period, visual bouncing disappears. Implications for a temporal window of audiovisual integration and the design of effective audiovisual warning signals are discussed.

Research paper thumbnail of The object and background hypothesis for vection

Vision Research, 2009

Stimulus attributes effective in inducing vection can be generalized by the object and background... more Stimulus attributes effective in inducing vection can be generalized by the object and background hypothesis, that is, properties that belong to 'objects' weaken vection while those of the 'background' enhance vection. We presented a motion-defined Rubin's vase to induce vection. Results clearly indicated that the background dominantly induced vection. We further demonstrated that motion stimuli that had a property of an object could not induce vection efficiently. Investigating vection in the framework of the object and background hypothesis provides a unified point of view for understanding vection stimuli.

Research paper thumbnail of Background stripes affect apparent speed of rotation

Journal of Vision, 2005

Introduction We have found that, when a line rotates at constant speed about its own center again... more Introduction We have found that, when a line rotates at constant speed about its own center against a background of stationary vertical stripes, it appears to vary in speed during each revolution, looking markedly faster when it passes through the vertical (figure 1a). Background stripes affect apparent speed of rotation

Research paper thumbnail of Inhibition of vection by red

Attention, Perception, & Psychophysics, 2010

We investigated the effects of colors on vection induction. Expanding optical flows during one's ... more We investigated the effects of colors on vection induction. Expanding optical flows during one's forward d self-motion were simulated by moving dots. The dots and the background were painted in equiluminant red and green. Experiments 1 and 2 showed that vection was weaker when the background was red than when the background was green. In addition, Experiment d 3 showed that vection was weaker when the moving dots were red than when the dots were green. Experiment k 4 demonstrated that red dots on a red background induced very weak vection, as compared with green dots on a green background. In Experiments 5 and 6, we showed that the present results could not be explained by a luminance artifact. Furthermore, Experiment d 7 showed that a moving red grating induced weaker vection than did a green one. We concluded that a red visual stimulus inhibits vection.

Research paper thumbnail of Effect of surrounding texture on the pursuit-pursuing illusion

i-Perception, 2014

The pursuit-pursuing illusion is a visual illusion where a circular object placed in the centre o... more The pursuit-pursuing illusion is a visual illusion where a circular object placed in the centre of a radial pattern consisting of thin sectors is seen to move in the pursuit eye movement direction. The present study investigates the role of the surrounding texture, replacing the sectors with random dots or stripes in an orientation that was orthogonal, parallel or oblique to the pursuit direction. The experiments demonstrate that the acquired illusory effect was large for the orthogonal stripes. However, each surrounding texture produces a relatively smaller effect than the radial sectors. These results suggest that a hypothesis based on the property of a centre-surround relative-motion detector cannot fully explain the illusion and that the radial stimulus structure itself plays an important role in this illusion.

Research paper thumbnail of Illusory depth perception of oblique lines produced by overlaid vertical disparity

Vision Research, 2005

Our visual system matches images from both eyes to establish a single view and stereo depth even ... more Our visual system matches images from both eyes to establish a single view and stereo depth even when they contain a certain amount of vertical disparity. This paper demonstrates a new stereo effect showing an aspect of vertical disparity processing. When oblique lines without disparity are overlaid with sparse random dots with vertical disparity, the lines look closer or farther in depth. The characteristics of this stereo illusion were experimentally investigated. The results showed that the sign of the perceived depth of the oblique lines depended on the combination of the line orientation and the vertical disparity sign, and that the amount of perceived depth became larger as the line orientation became more horizontal. The depth illusion robustly existed even under conditions that ruled out eye movements (i.e., vertical vergence and cyclovergence) by local-parallel or brief presentations of the stereo figures. This phenomenon suggests that the visual system locally measures vertical disparity and is not simply tolerating a small amount of vertical disparity. Stereo capture of vertical disparity and horizontal matching after vertical image shifts were proposed as possible explanations for the depth illusion.