RT Journal Article SR Electronic T1 Reconciling functional differences in populations of neurons recorded with two-photon imaging and electrophysiology JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.08.10.244723 DO 10.1101/2020.08.10.244723 A1 Joshua H. Siegle A1 Peter Ledochowitsch A1 Xiaoxuan Jia A1 Daniel Millman A1 Gabriel K. Ocker A1 Shiella Caldejon A1 Linzy Casal A1 Andrew Cho A1 Daniel J. Denman A1 Séverine Durand A1 Peter A. Groblewski A1 Greggory Heller A1 India Kato A1 Sara Kivikas A1 Jerome Lecoq A1 Chelsea Nayan A1 Kiet Ngo A1 Philip R. Nicovich A1 Kat R. North A1 Tamina K. Ramirez A1 Jackie Swapp A1 Xana Waughman A1 Ali Williford A1 Shawn R. Olsen A1 Christof Koch A1 Michael A. Buice A1 Saskia E. J. de Vries YR 2020 UL http://biorxiv.org/content/early/2020/08/11/2020.08.10.244723.abstract AB Extracellular electrophysiology and two-photon calcium imaging are widely used methods for measuring physiological activity with single-cell resolution across large populations of neurons in the brain. While these two modalities have distinct advantages and disadvantages, neither provides complete, unbiased information about the underlying neural population. Here, we compare evoked responses in visual cortex recorded in awake mice under highly standardized conditions using either imaging or electrophysiology. Across all stimulus conditions tested, we observe a larger fraction of responsive neurons in electrophysiology and higher stimulus selectivity in calcium imaging. This work explores which data transformations are most useful for explaining these modality-specific discrepancies. We show that the higher selectivity in imaging can be partially reconciled by applying a spikes-to-calcium forward model to the electrophysiology data. However, the forward model could not reconcile differences in responsiveness without sub-selecting neurons based on event rate or level of signal contamination. This suggests that differences in responsiveness more likely reflect neuronal sampling bias or cluster-merging artifacts during spike sorting of electrophysiological recordings, rather than flaws in event detection from fluorescence time series. This work establishes the dominant impacts of the two modalities’ respective biases on a set of functional metrics that are fundamental for characterizing sensory-evoked responses.Competing Interest StatementThe authors have declared no competing interest.