Two-photon calcium imaging in mice navigating a virtual reality environment.

Area of Science:

• Neuroscience
• Optical Imaging
• Animal Behavior

Background:

• Two-photon imaging is crucial for chronic measurement of genetically identified cell activity during behavior.
• Existing methods face challenges when applied to behaving animals in brightly lit virtual environments.

Purpose of the Study:

• To describe methods for performing two-photon imaging in mouse cortex during virtual reality (VR) navigation.
• To address key experimental challenges in this setup, including motion artifacts, light leak, and laser-induced tissue damage.

Main Methods:

• Detailed procedures for two-photon imaging in awake, behaving mice navigating a VR environment.
• Techniques to minimize brain motion artifacts and light leak from the VR projection system.
• Strategies to reduce laser-induced tissue damage during imaging.

Main Results:

• Successful implementation of two-photon imaging in mice during VR navigation.
• Demonstration of methods to overcome common experimental challenges.
• Provision of sample software for VR control and pupil tracking.

Conclusions:

• The described methods and resources facilitate the adaptation of conventional two-photon microscopes for use in behaving mice.
• Enables chronic, in vivo measurement of neural activity with cellular resolution during complex behaviors.
• Advances the study of neural circuits underlying behavior and cognition.