# Adaptively triggered comparisons enhance perceptual category learning: evidence from face learning

## TL;DR

A new adaptive learning method improves the ability to distinguish similar faces by using comparison trials triggered by learning errors.

## Contribution

A novel adaptive procedure called adaptively triggered comparisons (ATCs) is introduced to enhance perceptual category learning.

## Key findings

- Adaptively triggered comparisons significantly improved learning efficiency in facial identity recognition.
- Comparison trials generated by learning errors helped participants better distinguish similar categories.
- The adaptive method outperformed non-adaptive and single-item learning approaches.

## Abstract

Categorical learning is important and often challenging in both specialized domains, such as medical image interpretation, and commonplace ones, such as face recognition. Research has shown that comparing items from different categories can enhance the learning of perceptual classifications, particularly when those categories appear highly similar. Here, we developed and tested novel adaptively triggered comparisons (ATCs), in which errors produced during interactive learning dynamically prompted the presentation of active comparison trials. In a facial identity paradigm, undergraduate participants learned to recognize and name varying views of 22 unknown people. In Experiment 1, single-item classification trials were compared to a condition in which ATC trials were generated whenever a participant repeatedly confused two faces. Comparison trials required discrimination between simultaneously presented exemplars from the confused categories. In Experiment 2, an ATC condition was compared to a non-adaptive comparison condition. Participants learned to accuracy and speed criteria, and completed immediate and delayed posttests. ATCs substantially enhanced learning efficiency in both experiments. These studies, using a novel adaptive procedure guided by each learner’s performance, show that adaptively triggered comparisons improve category learning.