(https://www.nature.com/articles/s41598-024-70319-4)

Calcium imaging is a crucial and widely-used tool in modern systems neuroscience for monitoring neuronal activity. Typically, researchers assume that calcium transients reflect action potential firing. However, new findings by Milicevic et al. reveal that the strongest optical signals are generated when an action potential occurs on top of a plateau potential. Additionally, their research shows that even subthreshold electrical events—those without any action potentials—can produce noticeable calcium transients in optical recordings. These novel insights should be carefully considered when interpreting calcium imaging data.

 

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