Fast and light-efficient remote focusing for volumetric voltage imaging.

Area of Science:

• Neuroscience
• Biomedical Engineering
• Optical Imaging

Background:

• Voltage imaging allows noninvasive recording of electrical activity in excitable cells like neurons.
• High-speed, parallel imaging of large cell populations, especially in 3D volumes, remains a challenge.
• Existing remote focusing techniques are often too slow or light-inefficient for demanding applications.

Purpose of the Study:

• To develop a novel remote focusing technique for high-speed, efficient volumetric voltage imaging.
• To overcome the limitations of speed and light efficiency in current remote focusing methods.
• To enable parallel recording of electrical activity from a large number of neurons simultaneously.

Main Methods:

• Introduced flipped image remote focusing (FIRF), a novel remote focusing technique.
• FIRF doubles light efficiency compared to conventional beamsplitter methods.
• Combined FIRF with light-sheet imaging for volumetric voltage imaging.

Main Results:

• Achieved high-speed volumetric voltage imaging at 500 volumes/s.
• Demonstrated parallel recording from over 100 spontaneously active neurons.
• Successfully applied the technique to voltage imaging in the zebrafish spinal cord.

Conclusions:

• Flipped image remote focusing significantly enhances speed and light efficiency for voltage imaging.
• This technique enables unprecedented parallel recording of neuronal activity in vivo.
• Offers a powerful new tool for studying neural circuits and brain function.