The role of (micro)saccades and blinks in perceptual bi-stability from slant rivalry

• Published in: Vision research (Oxford) Vol. 45; no. 18; pp. 2417 - 2435
• Main Authors: van Dam, Loes C.J., van Ee, Raymond
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-08-2005; Elsevier Science
• Subjects: Biological and medical sciences; Blinking - physiology; Blinks; Cues; Fixation, Ocular; Fundamental and applied biological sciences. Psychology; Humans; Microsaccades; Perception; Perceptual bi-stability; Photic Stimulation - methods; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Psychophysics; Reaction Time; Saccades; Saccades - physiology; Slant rivalry; Vision; Vision Disparity - physiology; Vision, Binocular - physiology; Vision, Monocular - physiology; Visual Perception - physiology; Microsaccades; Saccades; Blinks; Slant rivalry; Perceptual bi-stability; Human; Stability; Saccadic eye movement; Binocular rivalry; Perspective; Perception; Binocular vision; Blinking
• ISSN: 0042-6989; 1878-5646
• DOI: 10.1016/j.visres.2005.03.013

We exposed the visual system to an ambiguous 3D slant rivalry stimulus consisting of a grid for which monocular (perspective) and binocular (disparity) cues independently specified a slant about a horizontal axis. When those cues specified similar slants, observers perceived a single slant. When the difference between the specified slants was large, observers alternatively perceived a perspective- or a disparity-dominated slant. Eye movement measurements revealed that there was no positive correlation between a perceptual flip and both saccades (microsaccades as well as larger saccades) and blinks that occurred prior to a perceptual flip. We also found that changes in horizontal vergence were not responsible for perceptual flips. Thus, eye movements were not essential to flip from one percept to the other. After the moment of a perceptual flip the occurrence probabilities of both saccades and blinks were reduced. The reduced probability of saccades mainly occurred for larger voluntary saccades, rather than for involuntary microsaccades. We suggest that the reduced probability of voluntary saccades reflects a reset of saccade planning.