Tracking prototype and exemplar representations in the brain across learning
Caitlin R Bowman, Takako Iwashita, Dagmar Zeithamova, Caitlin R Bowman, Takako Iwashita, Dagmar Zeithamova
Abstract
There is a long-standing debate about whether categories are represented by individual category members (exemplars) or by the central tendency abstracted from individual members (prototypes). Neuroimaging studies have shown neural evidence for either exemplar representations or prototype representations, but not both. Presently, we asked whether it is possible for multiple types of category representations to exist within a single task. We designed a categorization task to promote both exemplar and prototype representations and tracked their formation across learning. We found only prototype correlates during the final test. However, interim tests interspersed throughout learning showed prototype and exemplar representations across distinct brain regions that aligned with previous studies: prototypes in ventromedial prefrontal cortex and anterior hippocampus and exemplars in inferior frontal gyrus and lateral parietal cortex. These findings indicate that, under the right circumstances, individuals may form representations at multiple levels of specificity, potentially facilitating a broad range of future decisions.
Keywords: category learning; fmri; generalization; hippocampus; human; long term memory; neuroscience.
Conflict of interest statement
CB, TI, DZ No competing interests declared
© 2020, Bowman et al.
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References
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