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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

Subjective evaluation (mean and standard error) of motion illusion when looking at Riley’s and Kitaoka’s paintings in free viewing and fixation conditions (*p < 0.05; ***p < 0.001).
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Figure 2: Subjective evaluation (mean and standard error) of motion illusion when looking at Riley’s and Kitaoka’s paintings in free viewing and fixation conditions (*p < 0.05; ***p < 0.001).

Mentions: The results for the subjective evaluation of the sensation are presented in Figure 2 as a function of the stimulus (Riley’s and Kitaoka’s paintings) and viewing instructions (free viewing vs. fixation). For the comparison in terms of the viewing conditions, the data were analyzed using a Mann-Whitney U-test. As illustrated in Figure 2, the sensation of movement was significantly higher in the free viewing condition than in the fixation condition for Kitaoka’s painting (U = 50, p = 0.027). This difference was however not significant for Riley’s painting (U = 94.5, p = 0.87). The subjective evaluation data were also analyzed in terms of stimuli using a Wilcoxon test. The sensation of movement was significantly higher during the projection of Kitaoka’s painting than Riley’s work (Z = 3.85, p = 0.0001) and this difference was found to be significant in the condition with instruction for free viewing (Z = 3.47, p = 0.0005) but not in the fixation condition (Z = 1.66, p = 0.10).


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

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

Subjective evaluation (mean and standard error) of motion illusion when looking at Riley’s and Kitaoka’s paintings in free viewing and fixation conditions (*p < 0.05; ***p < 0.001).
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 2: Subjective evaluation (mean and standard error) of motion illusion when looking at Riley’s and Kitaoka’s paintings in free viewing and fixation conditions (*p < 0.05; ***p < 0.001).
Mentions: The results for the subjective evaluation of the sensation are presented in Figure 2 as a function of the stimulus (Riley’s and Kitaoka’s paintings) and viewing instructions (free viewing vs. fixation). For the comparison in terms of the viewing conditions, the data were analyzed using a Mann-Whitney U-test. As illustrated in Figure 2, the sensation of movement was significantly higher in the free viewing condition than in the fixation condition for Kitaoka’s painting (U = 50, p = 0.027). This difference was however not significant for Riley’s painting (U = 94.5, p = 0.87). The subjective evaluation data were also analyzed in terms of stimuli using a Wilcoxon test. The sensation of movement was significantly higher during the projection of Kitaoka’s painting than Riley’s work (Z = 3.85, p = 0.0001) and this difference was found to be significant in the condition with instruction for free viewing (Z = 3.47, p = 0.0005) but not in the fixation condition (Z = 1.66, p = 0.10).

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