A transparent μECoG array for simultaneous recording and optogenetic stimulation.

Area of Science:

• Neuroscience
• Materials Science
• Biomedical Engineering

Background:

• Micro-electrocorticography (μECoG) is crucial for high-resolution neural recording.
• Existing μECoG arrays can obstruct optical imaging, limiting combined electrophysiological and optical studies.
• Development of transparent electrode arrays is needed to overcome this limitation.

Purpose of the Study:

• To design, fabricate, and characterize a novel optically transparent electrode array for μECoG.
• To enable simultaneous neural recording and optical access to the cortex.
• To present detailed fabrication methods and performance data for transparent μECoG devices.

Main Methods:

• Fabrication of transparent μECoG arrays using Parylene C as a backing material.
• Sputtered indium tin oxide (ITO) and e-beam evaporated gold were used for transparent electrodes.
• Characterization included electrochemical impedance spectroscopy and light transmission measurements.

Main Results:

• Successful fabrication of a 49-channel μECoG array (800 μm pitch) and a 16-channel linear array (200 μm pitch).
• Demonstrated high optical transparency of the electrode array.
• Provided electrochemical impedance data indicating suitability for neural recording.

Conclusions:

• The developed optically transparent μECoG electrode array is a significant advancement for multimodal neural interfacing.
• This technology facilitates simultaneous electrophysiological recording and optical monitoring of neural activity.
• The fabricated devices show promising characteristics for future neuroscience research and clinical applications.