Multiple optical stimulation to neuron using Si opto-neural probe with multiple optical waveguides and metal-cover...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Optogenetics enables precise control of neural activity.
• Existing tools face challenges in light delivery and signal isolation.
• Need for integrated devices for simultaneous optical stimulation and neural recording.

Purpose of the Study:

• To develop and validate a novel silicon opto-neural probe.
• To achieve highly accurate, multisite optical stimulation with minimal light leakage.
• To demonstrate simultaneous neural recording and optical modulation.

Main Methods:

• Fabrication of a silicon neural probe with 16 recording sites and 3 optical waveguides.
• Integration of a metal cover to prevent light leakage.
• Electrochemical evaluation of recording site properties.
• In vivo testing for optical stimulation and local field potential (LFP) recording.
• Current source density (CSD) analysis of recorded LFPs.

Main Results:

• The probe exhibited suitable electrochemical properties for neural recording.
• Successful multisite optical stimulation of ChR2-expressing neurons was achieved.
• The metal cover effectively suppressed light leakage from optical waveguides.
• Optically modulated LFPs were successfully recorded in vivo.
• CSD analysis revealed light-induced membrane current sinks in the stimulated area.

Conclusions:

• The developed silicon opto-neural probe is a versatile tool for optogenetics.
• The probe enables precise, localized optical stimulation and high-fidelity neural recording.
• This technology advances the capabilities for studying neural circuits and functions.