On the scaling of size judgements by orientational cues

doi:10.1016/0042-6989(92)90200-3

Vision Research

Volume 32, Issue 8, August 1992, Pages 1433-1445

https://doi.org/10.1016/0042-6989(92)90200-3 Get rights and content

Abstract

Observers carried out multiple, concurrent size discriminations with a range of size standards. The task was to classify each stimulus as larger or smaller than the appropriate standard size for the set to which it belonged. The set to which each stimulus belonged was indicated by its orientation, or in different experiments, by its spatial location. Observers were able to maintain appropriate discrimination, both when there were four concurrent standards and when there were eight. Both angle and position functioned as effective cues. The size of the orientational cue appeared to make little difference to the efficiency of discrimination. However, when the relationship between standard size and orientation was random, rather than regular, performance got worse. The analogy between such discrimination and size constancy is pointed out, and the results are discussed in relation to Andrews D.P.'s [(1964) Quarterly Journal of Experimental Psychology, 16, 104–115)] account of perceptual calibration.

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Citation Excerpt :
First of all, we wanted to determine the extent to which inexperienced observers can compare test stimuli against multiple implicit standards within single blocks of trials. It is known from the results of Morgan (1992) and Morgan, Watamaniuk, and McKee (2000) that experienced observers can effectively perform such judgments with only modest (or sometimes no) reductions in precision. Even if younger inexperienced observers can effectively perform such judgments, it is not clear whether older adults (in our study, their ages ranged from 61 to 79 years) could do the same.
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On the scaling of size judgements by orientational cues

Abstract

Vision Research

Vision Research

Vision Research

Vision Research

Vision Research

Error-correcting perceptual mechanisms

Quarterly Journal of Experimental Psychology

A theory about the functional role and synaptic mechanisms of visual after-effects

On the locus of spatial frequency discrimination

Journal of the Optical Society of America A