The Effect of Temporal and Spatial Frequency on Phantom-Contour Detection

Phantom contours are a visual illusion that can define regions with distinctive boundaries when no real surrounding edges exist. Spatial-frequency sensitivity is known to vary reliably across the visual-processing pathways, as does temporal-frequency sensitivity. Given that the effect of temporal frequency on phantom-contour detection has been previously established, and that the relationship between spatial frequency and temporal frequency is known, two experiments were designed to measure the highest level of spatial frequency that would still allow reliable pattern detection at different temporal frequencies by using the phantom-contour paradigm. The results revealed that phantom-contour detection is impaired when the stimulus has a high spatial-frequency content and that phantom-contour perception is supported by low spatial frequencies.

[1]  DH Hubel,et al.  Psychophysical evidence for separate channels for the perception of form, color, movement, and depth , 1987, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[2]  J. Movshon,et al.  Cortical oscillatory responses do not affect visual segmentation , 1996, Vision Research.

[3]  David R. Badcock,et al.  The Effects of Contrast, Stimulus Duration, and Spatial Frequency on Visible Persistence in Normal and Specifically Disabled Readers. , 1981 .

[4]  D. Tolhurst,et al.  Psychophysical evidence for sustained and transient detectors in human vision , 1973, The Journal of physiology.

[5]  W. Lovegrove.  Do Dyslexics have a Visual Deficit , 1993 .

[6]  David J Heeger,et al.  Psychophysical evidence for a magnocellular pathway deficit in dyslexia , 1998, Vision Research.

[7]  Victor A. F. Lamme,et al.  Separate processing dynamics for texture elements, boundaries and surfaces in primary visual cortex of the macaque monkey. , 1999, Cerebral cortex.

[8]  R. Groner,et al.  Facets of dyslexia and its remediation , 1993 .

[9]  D. Tolhurst.  Separate channels for the analysis of the shape and the movement of a moving visual stimulus , 1973, The Journal of physiology.

[10]  Marius Usher,et al.  Visual synchrony affects binding and segmentation in perception , 1998, Nature.

[11]  B. Skottun,et al.  THE USE OF PHANTOM CONTOURS TO ISOLATE MAGNOCELLULAR AND PARVOCELLULAR RESPONSES , 2006, The International journal of neuroscience.

[12]  Mark S. Seidenberg,et al.  Selective magnocellular deficits in dyslexia: a “phantom contour” study , 2003, Neuropsychologia.

[13]  Diane C. Rogers-Ramachandran,et al.  Psychophysical evidence for boundary and surface systems in human vision , 1998, Vision Research.

[14]  J. Flanagan,et al.  Defining the limits of flicker defined form: effect of stimulus size, eccentricity and number of random dots , 2005, Vision Research.