Are Illusory Contours a Cause or a Consequence of Apparent Differences in Brightness and Depth in the Kanizsa Square?

The causal flows between the processes responsible for illusory contour clarity, brightness, and apparent depth in the Kanizsa square were examined. The sixty-four stimuli used consisted of all possible combinations of eight disk luminances and eight centre-to-centre separations between nearest disks. Ten subjects were instructed to rate the clarity of the illusory contour and the brightness and apparent depth differences between the Kanizsa square and its surround in each stimulus. On the basis of results obtained with the causal inference method, using partial correlations and path analysis, it is suggested that clarity of illusory contour can be influenced directly by disk separation, and that the output from the process responsible for illusory contour clarity has some effect on the processes responsible for the apparent depth and brightness differences.

[1]  T. Parks.  Subjective Figures: Some Unusual Concomitant Brightness Effects , 1980, Perception.

[2]  S. Coren,et al.  SUBJECTIVE CONTOURS AND APPARENT DEPTH , 2005 .

[3]  R. Day,et al.  A note on a second stage in the formation of illusory contours , 1980 .

[4]  D. Halpern,et al.  The Multiple Determination of Illusory Contours: 1. A Review , 1983, Perception.

[5]  J. Elashoff,et al.  Multiple Regression in Behavioral Research. , 1975 .

[6]  G. Kanizsa.  Subjective contours. , 1976, Scientific American.

[7]  T. Parks,et al.  Illusory figures: Individual differences apparent depth and lightness , 1985, Perception & psychophysics.

[8]  R. L. Gregory,et al.  A Look at Biological and Machine Perception , 1972 .

[9]  J. Kennedy,et al.  Illusory Line Linking Solid Rods , 1977, Perception.

[10]  Reply to Banks and Coffin. , 1974 .

[11]  L M Ward,et al.  Levels of processing in visual illusions: the combination and interaction of distortion-producing mechanisms. , 1979, Journal of experimental psychology. Human perception and performance.

[12]  R. Gregory,et al.  Cognitive Contours , 1972, Nature.

[13]  R. Day,et al.  26 – Subjective Contours, Visual Acuity, and Line Contrast , 1978 .

[14]  T. Oyama,et al.  Span of attention, backward masking, and reaction time , 1981, Perception & psychophysics.

[15]  B. Richardson.  The Nonequivalence of Abrupt and Diffuse Illusory Contours , 1979, Perception.

[16]  T. Parks,et al.  Sharp-edged vs. diffuse illusory circles: The effects of varying luminance , 1983, Perception & psychophysics.

[17]  R. Day,et al.  The Relationship between Brightness Contrast and Illusory Contours , 1979, Perception.

[18]  D. Halpern,et al.  The Determinants of Illusory-Contour Perception , 1981, Perception.

[19]  Susan T. Dumais,et al.  The effects of illumination level and retinal size on the apparent strength of subjective contours , 1976 .

[20]  W. L. Brigner,et al.  Subjective Contour: Apparent Depth or Simultaneous Brightness Contrast? , 1974, Perceptual and motor skills.

[21]  R. Reynolds,et al.  Perception of an Illusory Contour as a Function of Processing Time , 1981, Perception.

[22]  A. Gellatly.  Perception of an Illusory Triangle with Masked Inducing Figure , 1980, Perception.

[23]  J. Frisby,et al.  Illusory Contours: Curious Cases of Simultaneous Brightness Contrast? , 1975 .

[24]  H. Simon,et al.  Spurious Correlation: A Causal Interpretation* , 1954 .

[25]  Hubert M. Blalock,et al.  Four-Variable Causal Models and Partial Correlations , 1962, American Journal of Sociology.

[26]  T. Parks.  Illusory figures: a (mostly) atheoretical review. , 1984, Psychological bulletin.

[27]  D. Halpern,et al.  The Multiple Determination of Illusory Contours: 2. An Empirical Investigation , 1983, Perception.

[28]  Tadasu Oyama,et al.  Perceived size and perceived distance in stereoscopic vision and an analysis of their causal relations , 1974 .

[29]  E M Brussell,et al.  Sensory information and subjective contour. , 1977, The American journal of psychology.