Multipoint-emitting optical fibers for spatially addressable in vivo optogenetics

Area of Science:

• Neuroscience
• Biomedical Engineering
• Optogenetics

Background:

• Optogenetics enables precise control of neural activity for circuit mapping.
• Current methods using single optical fibers illuminate a limited brain volume.
• Need for advanced techniques to target multiple neural regions simultaneously.

Purpose of the Study:

• To develop and validate a novel tapered optical fiber for multipoint in vivo optogenetic stimulation.
• To enable selective and dynamic illumination of different brain regions using a single implant.
• To minimize invasiveness in neural circuit investigations.

Main Methods:

• Fabrication of a tapered optical fiber with multiple patterned light windows using focused ion beam milling.
• Development of a simple input coupling strategy for site selection.
• In vivo testing in mouse models, coupling the fiber with a microelectrode array for simultaneous recording and stimulation.

Main Results:

• Demonstrated selective and dynamic illumination of distinct brain regions along the fiber taper.
• Successfully performed multipoint optical stimulation in the mammalian brain in vivo.
• Achieved simultaneous extracellular recording and stimulation at multiple sites in the mouse striatum and cerebral cortex.

Conclusions:

• The novel tapered optical fiber offers a minimally invasive solution for multipoint optogenetic control.
• This technology advances the ability to investigate complex neural circuitry in vivo.
• Enables dynamic, site-specific neural modulation for enhanced brain function studies.