“Weber's law” for position: the role of spatial frequency and contrast

@article{Levi1992WebersLF,
  title={“Weber's law” for position: the role of spatial frequency and contrast},
  author={Dennis Michael Levi and Stanley A. Klein},
  journal={Vision Research},
  year={1992},
  volume={32},
  pages={2235-2250}
}
Isolation of stimulus characteristics contributing to Weber's law for position
To examine the independent contribution of various stimulus characteristics to positional judgements, we measured vernier alignment performance for three types of Gabor stimuli. In one, only the
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  • Physics, Medicine
    Journal of the Optical Society of America. A, Optics, image science, and vision
  • 1995
TLDR
The findings of this study suggest that, although shifts in spatial scale of the underlying low-level oriented mechanisms may contribute to increased misalignment thresholds with increasing separation, additional factors, such as positional uncertainty associated with eccentricity per se, are limiting.
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Disentangling the Role of Spatial Scale, Separation and Eccentricity in Weber's Law for Position
TLDR
It is found that Weber's law occurs at individual spatial scales, and holds true not just for stimuli positioned either side of fixation, but for any series of stimuli which possess the same ratio of separation to eccentricity.
A comparison of vernier acuity for narrowband and broadband stimuli.
TLDR
The results provide support for filter models of vernier acuity by showing that verniers performance for abutting and closely-separated broadband stimuli represents the envelope of Vernonier sensitivity of those spatial frequency mechanisms that are activated by the broadband stimulus.
Intrinsic uncertainty and integration efficiency in bisection acuity
TLDR
Two different forms of sigma i indicate that bisection judgments are limited by at least two separate sources of limiting noise, consistent with the hypothesis of two separate mechanisms (i.e. spatial filters and local signs).
Configuration specificity in bisection acuity
TLDR
The dependence of bisection discrimination on similarity between the elements of the stimulus demonstrates that the encoding of spatial location and spatial extent are coupled to the coding of other stimulus properties.
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