Generalization of learning can arise from 2 distinct sources: failure to discriminate a novel test stimulus from the trained stimulus and active extrapolation from the trained stimulus to the test stimulus despite them being discriminable. We investigated these 2 processes in a predictive learning task by testing stimulus discriminability…

It is common to see mirror errors in letters in early stages of reading due to the mirror-generalization process that allows a visual stimulus to be identified independently of its orientation. To avoid such errors, this process must be inhibited. A special case would be children with dyslexia since their difficulties with the alphabetic code may…

Learning to categorize perceptually similar stimuli can result in people becoming more sensitive to differences along perceptual dimensions that are relevant to category membership and/or less sensitive to equivalent differences along irrelevant perceptual dimensions. These effects of acquired distinctiveness and acquired equivalence may be caused…

Building conceptual knowledge that generalizes to novel situations is a key function of human memory. Category-learning paradigms have long been used to understand the mechanisms of knowledge generalization. In the present study, we tested the conditions that promote formation of new concepts. Participants underwent 1 of 6 training conditions that…

Two experiments tested whether a peak-shifted generalization gradient could be explained by the averaging of distinct gradients displayed in subgroups reporting different generalization rules. Across experiments using a causal judgment task (Experiment 1) and a fear conditioning paradigm (Experiment 2), we found a close concordance between…

Generalization of fear can involve abnormal responding to cues that signal safety and is common in people diagnosed with post-traumatic stress disorder. Differential auditory fear conditioning can be used as a tool to measure changes in fear discrimination and generalization. Most prior work in this area has focused on elevated amygdala activity…