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Updated: Jul 18, 2026

Manipulation of Color Patterns in Jumping Spiders for Use in Behavioral Experiments
Published on: May 21, 2019
Contamination vs. harm-relevant outcome expectancies and covariation bias in spider phobia
Peter J de Jong1, Madelon L Peters
1Department of Developmental and Clinical Psychology, University of Groningen, Grote Kruisstraat 1/2, 9712 TS Groningen, The Netherlands. p.j.de.jong@rug.nl
Abstract:
There is increasing evidence that spiders are not feared because of harmful outcome expectancies but because of disgust and contamination-relevant outcome expectancies. This study investigated the relative strength of contamination- and harm-relevant UCS expectancies and covariation bias in spider phobia. High (n=25) and low (n=24) spider fearful individuals saw a series of slides comprising spiders, pitbulls, maggots, and rabbits. Slides were randomly paired with either a harm-relevant outcome (electrical shock), a contamination-related outcome (drinking of a distasting fluid), or nothing. Spider fearful individuals displayed a contamination-relevant UCS expectancy bias associated with spiders, whereas controls displayed a harm-relevant expectancy bias. There was no evidence for a (differential) postexperimental covariation bias; thus the biased expectancies were not robust against refutation. The present findings add to the evidence that contamination ideation is critically involved in spider phobia.
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