An adaptive excitation source for high-speed multiphoton microscopy.

Optical imaging is important for understanding brain function. However, established methods with high spatiotemporal resolution are limited by the potential for laser damage to living tissues. We describe an adaptive femtosecond excitation source that only illuminates the region of interest, which leads to a 30-fold reduction in the power requirement for two- or three-photon imaging of brain activity in awake mice for improved high-speed longitudinal neuroimaging.