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Within-trial contrast: when you see it and when you don't
1Department of Psychology, University of Kentucky, Lexington, Kentucky 40506-0044, USA. zentall@uky.edu
Learning & Behavior
|March 6, 2008
Summary
Replication failures in within-trial contrast studies may stem from insufficient training or prior experience with lean reinforcement schedules. These factors can reduce the perceived aversiveness, thus impacting the contrast effect in animal behavior research.
Area of Science:
- Behavioral neuroscience
- Animal cognition
- Learning theory
Background:
- Within-trial contrast describes a preference for stimuli following aversive events.
- Recent studies have reported failures to replicate this effect.
- Potential factors influencing replicability include training duration and prior experimental history.
Discussion:
- Insufficient training sessions may prevent the establishment of the contrast effect.
- Prior experience with lean schedules of reinforcement can diminish the perceived aversiveness of demanding tasks.
- This prior experience may thus interfere with the occurrence of within-trial contrast.
Key Insights:
- Replication failures in within-trial contrast are likely attributable to methodological factors.
- Inadequate training and prior exposure to lean schedules are identified as key contributors.
- These factors can alter the subjective value of stimuli, affecting behavioral outcomes.
Outlook:
- Future research should ensure adequate training protocols and consider the impact of prior reinforcement histories.
- Further investigation into the role of schedule-thinning in modulating contrast effects is warranted.
- Standardizing experimental conditions will enhance the reliability and validity of findings in this area.
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