Related Experiment Video
Updated: Jul 17, 2026

Perceptual and Category Processing of the Uncanny Valley Hypothesis' Dimension of Human Likeness: Some Methodological Issues
Published on: June 3, 2013
What limits simultaneous discrimination accuracy?
J P Thomas1, S Magnussen, M W Greenlee
1Psychology Department, UCLA, Box 951563, CA 90095-1563, Los Angeles, USA. thomas@psych.ucla.edu
Abstract:
Discrimination accuracy decreases when viewers simultaneously monitor two perceptually distinct stimulus components for changes in a common property, e.g. contrast [Magnussen & Greenlee (1997). Journal of Experimental Psychology: Human Perception and Performance, 23, 1603-1616; Olzak & Wickens (1997). Perception, 26, 1101-1120]. We ask whether the limitation is in monitoring two components or in making dual decisions about a single property. Using the same uncertainty paradigm as Magnussen and Greenlee, we find no evidence of a processing limitation when viewers simultaneously monitor one component (1.25 c/d) for a possible change in contrast and a second component (5 c/d) for a possible change in spatial frequency, regardless of whether the components are spatially separated or superimposed. The limitation is in making dual decisions about a single property.
Related Concept Videos
Confirmation Biases
Stereotypes, Prejudice, and Discrimination
Difference from Background: Limit of Detection
The LOD indicates the presence or absence...
Accuracy and Errors in Hypothesis Testing
In hypothesis testing, the probability of making a Type I error, denoted as α, is commonly set at 0.05. This significance level indicates a 5% chance...

