The role of perception in generalization: Commentary on Zaman, Yu, & Verheyen (2023)

Abstract

Stimulus generalization is a critical ability for adaptation to everyday life. In a typical experiment, generalization is assessed by measuring responses to stimuli varying along a physical dimension. Variations in the gradient of learned responses are usually interpreted as differences in the underlying cognitive process of generalization. A recent study by Zaman, Yu, and Verheyen (2023) seeks to challenge this view, arguing that generalization is best modelled by perceptual factors and that individual differences in perception are a primary driver of generalization. In this commentary, we outline issues in the methodology and analysis of Zaman et al., and show that their key result is not robust to the addition of theoretically-informed alternative models. We conclude thatalthough it is clear that perceptual processes play an important role in generalization, the evidence is not strong enough to support their conclusions. We propose some ways forward for researchers in this field attempting to answer the important but complex question of determining the contribution of perception in stimulus generalization.