The sensitivity of separation discrimination to spatiotemporal jitter

doi:10.1016/0042-6989(90)90143-9

Vision Research

Volume 30, Issue 11, 1990, Pages 1555-1560

https://doi.org/10.1016/0042-6989(90)90143-9 Get rights and content

Abstract

Differences of less than 20 sec of visual angle in the separation of a pair of closely spaced parallel lines can be reliably detected. This ability is known as a hyperacuity because the thresholds are smaller than the diameter of one foveal cone. It is shown that this ability does not require a stationary pattern. Indeed, correlated horizontal jitter of the line pair has little detrimental effect on performance for jitter that ranges up to 8 min arc for two lines with a separation of only 6 min arc. Uncorrelated jitter of the two lines, which allows the actual separation to vary from moment to moment, causes performance to deteriorate at a rate similar to the rise of signal uncertainty. The results reflect the operation of a system which is not only extremely robust to oculomotor instability but is also robust to positional variation that could not be produced by eye movements.

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Citation Excerpt :
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The eyes are in continuous motion. A robust system required to make spatial separation judgments should be resistant to the positional noise produced by such movements. Two parallel lines have been jittered horizontally in order to assess the impact of stimulus movement on the retina. Jitter that maintains the separation between the two lines has minimal effect on separation discrimination thresholds, regardless of whether the targets in the two eyes jitter in a positively correlated, negatively correlated or uncorrelated manner. Presenting both eyes with line pairs but only altering the separation in one eye in the second interval yields poorer performance. However, if one eye receives a change in separation while the other views a dark screen then that monocular threshold is very similar to the binocular threshold. These results are most simply explained by procedures which average the monocular separation estimates.
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The sensitivity of separation discrimination to spatiotemporal jitter

Abstract

Vision Research

Vision Research

Vision Research

Vision Research

Spatial location and hyperacuity: Flank position in the centre and surround zones

Spatial Vision

Quantitative relations among vernier, real depth, and stereoscopic depth acuities

Journal of Experimental Psychology

Eye-movements and visual perception