Generalization from previous experiences to new situations is a hallmark of intelligent behavior and a prerequisite for category learning. It has been proposed that category learning in humans relies on multiple brain systems that compete with each other, including an explicit, rule-based system and an implicit system. Given that humans are biased to follow rule-based strategies, a counterintuitive prediction of this model is that other animals, in which this rule-based system is less developed, might generalize better to new stimuli in implicit category-learning tasks that are not rule-based. To test this prediction, rats and humans were trained in rule-based and information-integration category-learning tasks with visual stimuli. The generalization performance of rats and humans was equal in rule-based categorization, but rats outperformed humans on generalization in the information-integration task. The performance of rats was consistent with a nondimensional, similarity-based categorization strategy. These findings illustrate through a comparative approach that the bias toward rule-based strategies can impede humans’ performance on generalization tasks.
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This research was supported by Grant Nos. G.0819.11, G.0562.10, and GOA/12/008. B.V. is currently a postdoctoral fellow of the Research Foundation Flanders.
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Vermaercke, B., Cop, E., Willems, S. et al. More complex brains are not always better: rats outperform humans in implicit category-based generalization by implementing a similarity-based strategy. Psychon Bull Rev 21, 1080–1086 (2014). https://doi.org/10.3758/s13423-013-0579-9
- Animal behavior
- Implicit/explicit cognition
- Visual perception