Imaging local brain activity of multiple freely moving mice sharing the same environment

Area of Science:

• Neuroscience
• Biotechnology
• Animal Behavior

Background:

• Electrophysiological field potential dynamics are crucial for understanding brain function and psychiatric disorders.
• Current methods often limit recordings to stationary subjects, hindering studies on social behavior in freely moving animals.

Purpose of the Study:

• To develop a fiber-free recording method for dynamic brain activity in freely moving subjects.
• To enable simultaneous recordings from multiple interacting mice.
• To investigate brain activation patterns during social interaction.

Main Methods:

• Utilized a novel bioluminescent voltage indicator, LOTUS-V.
• Implemented a fiber-free recording system for high-fidelity electrophysiological measurements.
• Recorded brain activity from multiple independently moving mice during social interaction.

Main Results:

• Successfully captured dynamic brain activity changes in freely moving mice.
• The ratiometric nature of LOTUS-V minimized motion and head-angle artifacts.
• Demonstrated simultaneous recordings from multiple interacting mice.
• Discovered activation of the primary visual cortex during mouse social interaction.

Conclusions:

• The proposed fiber-free LOTUS-V recording method is effective for studying brain dynamics in freely moving, socially interacting animals.
• This methodology overcomes limitations of traditional electrophysiology, enabling new insights into neurobiology and psychiatry.
• The findings highlight the role of the primary visual cortex in social interactions.