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bioRxiv · 10.1101/2023.10.09.560813

Striatal calcium transients detected by fiber photometry propagate to axons

Lipton, D. M.·Tamimi, M.·Shalom, I.·Sheinfeld, T.·Gonzales, B. J.·Groysman, M.·Citri, A.
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Abstract

ARISING FROM: A. Legaria et al., Nature Neuroscience https://doi.org/10.1038/s41593-022-01152-z (2022). Calcium fiber photometry is a popular technique for recording the activity of neuronal populations defined by their gene expression or connectivity. In a recent study, Legaria et al., present evidence that the calcium signal recorded with fiber photometry primarily reports local fluctuations in neuropil Ca2+, rather than somatic Ca2+ influx corresponding to neural firing, as has been assumed by the field. This raises the question of whether fiber photometry transients are a valid measure of the propagation of information from neural soma to their axons. We addressed this question directly, recording coincident activity from both the somato-dendritic region and downstream axons of striatal neural populations. Our findings demonstrate that calcium events are reliably propagated to axons, supporting the interpretation that these events reflect neuronal firing.

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Lipton, D. M., Tamimi, M., Shalom, I., Sheinfeld, T., Gonzales, B. J., Groysman, M., Citri, A.. 2023-10-10. Striatal calcium transients detected by fiber photometry propagate to axons. https://doi.org/10.1101/2023.10.09.560813

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