Related Experiment Video
Updated: May 21, 2026
09:45
New Variations for Strategy Set-shifting in the Rat
Published on: January 23, 2017
Stochastic choice drives variability in patch foraging decisions in humans and rats
Emma V Scholey1,2,3, Matthew A J Apps4,5, Mark D Humphries6
1Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham, UK. e.v.scholey@bham.ac.uk.
Communications Psychology
|May 19, 2026
Summary
Foraging animals exhibit variability in resource decisions. Stochastic choice explains this variability and predicts that leaving decisions are independent of rewards and use suboptimal internal functions.
Area of Science:
- Behavioral Ecology
- Decision Neuroscience
- Animal Behavior
Background:
- Foraging theory predicts when animals should leave depleting resources, but real-world behavior shows significant variability.
- This variability is often attributed to stochastic decision-making, allowing for exploration of alternatives.
Purpose of the Study:
- To investigate if stochastic choice can explain variability in sequential foraging decisions.
- To explore the predictions of stochastic choice models regarding foraging behavior and internal mechanisms.
Main Methods:
- Analysis of patch foraging datasets from human (n=39, n=29) and rat (n=8) participants.
- Modeling foraging decisions using a stochastic choice framework.
Main Results:
- Stochastic choice sufficiently explains the observed variability in when foragers leave a patch.
- Validated two counterintuitive predictions: leaving variability is independent of environmental rewards, and foragers use a suboptimal internal function for choice stochasticity.
Conclusions:
- Stochastic choice is a significant, underappreciated factor in foraging decisions.
- Behavioral variability can reveal underlying algorithmic mechanisms of decision-making.
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