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bioRxiv · 10.1101/686063

Experience shapes activity dynamics and stimulus coding of VIP inhibitory and excitatory cells

Abstract

Cortical circuits are flexible and can change with experience and learning. However, the effects of experience on specific cell types, including distinct inhibitory types, are not well understood. Here we investigated how excitatory and VIP inhibitory cells in layer 2/3 of mouse visual cortex were impacted by visual experience in the context of a behavioral task. Mice learned to perform an image change detection task with a set of eight natural scene images, viewing these images thousands of times. Subsequently, during 2-photon imaging experiments, mice performed the task with these familiar images and three additional sets of novel images. Novel images evoked stronger overall activity in both excitatory and VIP populations, and familiar images were more sparsely coded by excitatory cells. The temporal dynamics of VIP activity differed markedly between novel and familiar images: VIP cells were stimulus-driven by novel images but displayed ramping activity during the inter-stimulus interval for familiar images. Moreover, when a familiar stimulus was omitted from an expected sequence, VIP cells showed extended ramping activity until the subsequent image presentation. This prominent shift in response dynamics suggests that VIP cells may adopt different modes of processing during familiar versus novel conditions.\n\nHIGHLIGHTSO_LIExperience with natural images in a change detection task reduces overall activity of cortical excitatory and VIP inhibitory cells\nC_LIO_LIEncoding of natural images is sharpened with experience in excitatory neurons\nC_LIO_LIVIP cells are stimulus-driven by novel images but show pre-stimulus ramping for familiar images\nC_LIO_LIVIP cells show strong ramping activity during the omission of an expected stimulus\nC_LI

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Garrett, M. E., Manavi, S., Roll, K., Ollerenshaw, D. R., Groblewski, P. A., Kiggins, J., Jia, X., Casal, L., Mace, K., Williford, A., Leon, A., Mihalas, S., Olsen, S. R.. 2019-06-28. Experience shapes activity dynamics and stimulus coding of VIP inhibitory and excitatory cells. https://doi.org/10.1101/686063

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