A closer look at four-dot masking of a foveated target.
Four-dot masking with a common onset mask was recently demonstrated in a fully attended and foveated target (Filmer, Mattingley & Dux, 2015). Here, we replicate and extend this finding by directly comparing a four-dot mask with an annulus mask while probing masking as a function of mask duration, and target-mask separation. Our results suggest that while an annulus mask operates via spatially local contour interactions, a four-dot mask operates through spatially global mechanisms. We also measure how the visual system's representation of an oriented bar is impacted by a four-dot mask, and find that masking here does not degrade the precision of perceived targets, but instead appears to be driven exclusively by rendering the target completely invisible.
Centre for Vision Research, York University , Toronto, Ontario , Canada.
Marwan
M
Daar
Centre for Vision Research, York University , Toronto, Ontario , Canada.
Hugh R
HR
Wilson
Four-dot masking; Masking; Object substitution masking; Psychophysics; Spatial vision