Category learning biases sensory representations in human visual cortex

Word Count: 234 Article Word Count (inc. References & Fig Captions): 5011 Reference Count: 29 Figure Count: 6 *Correspondence: Edward Ester Department of Psychology and FAU Brain Institute Florida Atlantic University 777 Glades Rd. Boca Raton, FL. 33431 [email protected] Acknowledgments: Funding provided by NIH R01 EY025872 (J.T.S.) and a James S. McDonnell Foundation award (J.T.S.). E.F.E., conceived and designed the experiment, collected and analyzed the data, and wrote the paper. T.C.S. provided conceptual input during all phases of the project and edited the paper. J.T.S. supervised all phases of the project. The authors declare no competing interests. Data Availability: All data and analytic software are publicly available on the Open Sciences Framework at https://osf.io/xzay8/ Significance Statement: Category learning alters perceptual sensitivity by enhancing the discriminability of similar exemplars from different categories. These distortions could in part reflect changes in how sensory neural populations selective for category-defining features encode information. To test this possibility, we used multivariate analytical techniques to reconstruct and quantify representations of oriented stimuli after observers had learned to classify them into two discrete groups. Representations of orientation encoded by several early visual areas were systematically biased according to their category membership, with larger biases for orientations adjacent to the boundary that defined each category. This result suggests that categorizing a stimulus alters how that stimulus is represented at the earliest stages of the visual processing hierarchy. . CC-BY-NC-ND 4.0 International license peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was not . http://dx.doi.org/10.1101/170845 doi: bioRxiv preprint first posted online Aug. 1, 2017;