The Role of Depth and 1/f Dynamics in Perceiving Reversible
Figures
D. J. Aks
Department of Psychology, University of Wisconsin - Whitewater,
Whitewater, WI 53190
J. C. Sprott
Department of Physics, 1150 University Ave, University
of Wisconsin - Madison, Madison, WI 53706
ABSTRACT
When confronted with a reversible figure, such as the Necker Cube,
viewers
experience a spontaneously changing percept. We assess the dynamic of
how
the human visual system resolves perceptual ambiguity in stimuli that
offer
multiple interpretations. Subjects observed the Necker cube for one of
three viewing durations during which they pressed a key each time they
perceived a change in the orientation of the cube. Manipulations of
binocular
disparity served as a parameter to control perceptual stability.
Low-depth
conditions yielded more perceptual reversals than high-depth
conditions.
A Fourier analysis performed on the time series of reversals show 1/f
(pink) noise was evident in their power spectra. These results together
with theoretical models of complex systems (e.g., Bak, Tang, &
Wiesenfeld,
1987) suggest that depth information may guide our perceptual system
into
a self-organized state to assist us in resolving ambiguous information.
Moreover, slopes of the spectra were steeper in high-depth and brief
viewing
conditions, suggesting that the visual system relies more on previous
perceptual
states and filters more white noise in these conditions.
Ref: D. J. Aks and J.
C. Sprott, Nonlinear Dynamics, Psychology, and Life Sciences 7,
161-180
(2003).
The complete paper is available in PDF
format.
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