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Eye movement instructions modulate motion illusion and body sway with Op Art.

Kapoula Z, Lang A, Vernet M, Locher P - Front Hum Neurosci (2015)

Bottom Line: Op Art generates illusory visual motion.Twenty-eight healthy adults in orthostatic stance were successively exposed to three visual stimuli consisting of one figure representing a cross (baseline condition) and two Op Art paintings providing sense of motion in depth-Bridget Riley's Movements in Squares and Akiyoshi Kitaoka's Rollers.Posture was measured for 30 s per condition using a body fixed sensor (accelerometer).

View Article: PubMed Central - PubMed

Affiliation: IRIS Team, Physiopathology of Binocular Motor Control and Vision, Neurosciences, UFR Biomédicale, CNRS, University Paris V Paris, France.

ABSTRACT
Op Art generates illusory visual motion. It has been proposed that eye movements participate in such illusion. This study examined the effect of eye movement instructions (fixation vs. free exploration) on the sensation of motion as well as the body sway of subjects viewing Op Art paintings. Twenty-eight healthy adults in orthostatic stance were successively exposed to three visual stimuli consisting of one figure representing a cross (baseline condition) and two Op Art paintings providing sense of motion in depth-Bridget Riley's Movements in Squares and Akiyoshi Kitaoka's Rollers. Before their exposure to the Op Art images, participants were instructed either to fixate at the center of the image (fixation condition) or to explore the artwork (free viewing condition). Posture was measured for 30 s per condition using a body fixed sensor (accelerometer). The major finding of this study is that the two Op Art paintings induced a larger antero-posterior body sway both in terms of speed and displacement and an increased motion illusion in the free viewing condition as compared to the fixation condition. For body sway, this effect was significant for the Riley painting, while for motion illusion this effect was significant for Kitaoka's image. These results are attributed to macro-saccades presumably occurring under free viewing instructions, and most likely to the small vergence drifts during fixations following the saccades; such movements in interaction with visual properties of each image would increase either the illusory motion sensation or the antero-posterior body sway.

No MeSH data available.


Related in: MedlinePlus

Cross figure (A) for baseline condition and Riley’s Movement in Squares (B) and Kitaoka’s Rollers (C) paintings.
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Figure 1: Cross figure (A) for baseline condition and Riley’s Movement in Squares (B) and Kitaoka’s Rollers (C) paintings.

Mentions: Stimuli consisted of one figure composed of a cross, i.e., two perpendicular lines measuring 40 cm each, i.e., ~11.4° of visual angle (baseline condition) and two Op Art paintings–Bridget Riley’s (1961) Movement in Squares and Akiyoshi Kitaoka’s (2004) Rollers. Figure 1 contains an image of each stimulus. The original Op Art paintings measure 122 × 122 cm and 131 × 92 cm, respectively. These two paintings were chosen because both images provide the 3D appearance of movement in depth as indicated by a preliminary study, in which observers indicated a strong sensation of movement in both artworks. In addition, in the present study the participants indicate comparable illusory motions for these two artworks (see below). Furthermore, Kitakoa’s painting was used because there is scientific work on the psychophysical properties of this stimulus and hypotheses on the mechanisms explaining motion sensation including the role of eye movements (see Fermüller et al., 2010). Additionally, many of Bridget Riley’s Op Art paintings have been used as stimuli in a number of investigations of movement perception and optical illusions (see, e.g., Nather et al., 2013).


Eye movement instructions modulate motion illusion and body sway with Op Art.

Kapoula Z, Lang A, Vernet M, Locher P - Front Hum Neurosci (2015)

Cross figure (A) for baseline condition and Riley’s Movement in Squares (B) and Kitaoka’s Rollers (C) paintings.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4374464&req=5

Figure 1: Cross figure (A) for baseline condition and Riley’s Movement in Squares (B) and Kitaoka’s Rollers (C) paintings.
Mentions: Stimuli consisted of one figure composed of a cross, i.e., two perpendicular lines measuring 40 cm each, i.e., ~11.4° of visual angle (baseline condition) and two Op Art paintings–Bridget Riley’s (1961) Movement in Squares and Akiyoshi Kitaoka’s (2004) Rollers. Figure 1 contains an image of each stimulus. The original Op Art paintings measure 122 × 122 cm and 131 × 92 cm, respectively. These two paintings were chosen because both images provide the 3D appearance of movement in depth as indicated by a preliminary study, in which observers indicated a strong sensation of movement in both artworks. In addition, in the present study the participants indicate comparable illusory motions for these two artworks (see below). Furthermore, Kitakoa’s painting was used because there is scientific work on the psychophysical properties of this stimulus and hypotheses on the mechanisms explaining motion sensation including the role of eye movements (see Fermüller et al., 2010). Additionally, many of Bridget Riley’s Op Art paintings have been used as stimuli in a number of investigations of movement perception and optical illusions (see, e.g., Nather et al., 2013).

Bottom Line: Op Art generates illusory visual motion.Twenty-eight healthy adults in orthostatic stance were successively exposed to three visual stimuli consisting of one figure representing a cross (baseline condition) and two Op Art paintings providing sense of motion in depth-Bridget Riley's Movements in Squares and Akiyoshi Kitaoka's Rollers.Posture was measured for 30 s per condition using a body fixed sensor (accelerometer).

View Article: PubMed Central - PubMed

Affiliation: IRIS Team, Physiopathology of Binocular Motor Control and Vision, Neurosciences, UFR Biomédicale, CNRS, University Paris V Paris, France.

ABSTRACT
Op Art generates illusory visual motion. It has been proposed that eye movements participate in such illusion. This study examined the effect of eye movement instructions (fixation vs. free exploration) on the sensation of motion as well as the body sway of subjects viewing Op Art paintings. Twenty-eight healthy adults in orthostatic stance were successively exposed to three visual stimuli consisting of one figure representing a cross (baseline condition) and two Op Art paintings providing sense of motion in depth-Bridget Riley's Movements in Squares and Akiyoshi Kitaoka's Rollers. Before their exposure to the Op Art images, participants were instructed either to fixate at the center of the image (fixation condition) or to explore the artwork (free viewing condition). Posture was measured for 30 s per condition using a body fixed sensor (accelerometer). The major finding of this study is that the two Op Art paintings induced a larger antero-posterior body sway both in terms of speed and displacement and an increased motion illusion in the free viewing condition as compared to the fixation condition. For body sway, this effect was significant for the Riley painting, while for motion illusion this effect was significant for Kitaoka's image. These results are attributed to macro-saccades presumably occurring under free viewing instructions, and most likely to the small vergence drifts during fixations following the saccades; such movements in interaction with visual properties of each image would increase either the illusory motion sensation or the antero-posterior body sway.

No MeSH data available.


Related in: MedlinePlus