Fluorescence imaging of calcium dynamics has transformed cellular biology, particularly in neuroscience, enabling the study of neural activity in precisely defined spatial populations. Commonly used ratiometric measures, like ΔF/F, rely on baseline definitions, posing challenges outside evoked responses and requiring individual cell-specific baselines. This study introduces a novel quantitative measure called ARES (Autoregressive RESiduals), leveraging the time dimension of the signal. ARES, based on autoregression residuals, eliminates the need for arbitrary baseline assignment. We outline ARES’s characteristics, compare it to ΔF/F, and demonstrate enhanced spatial and temporal resolution in calcium data recording. The utility of ARES is exemplified in investigating intracellular calcium dynamics, showcasing its effectiveness in tracking calcium wave propagation within a dendrite. As a robust and precise method for fluorescence signal quantification, ARES is well-suited for studying both spontaneous and evoked calcium dynamics, subcellular calcium signal localization, and spatiotemporal tracking of calcium fluctuations.

Nonlinear super-resolution signal processing allows intracellular tracking of calcium dynamics

Niccolò Calcini, Angelica da Silva Lantyer, Fleur Zeldenrust, Tansu Celikel