Spatially controlled, bipolar, cortical stimulation with high-capacitance, mechanically flexible subdural surface...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Neuromodulation often uses invasive penetrating electrodes, risking cortical damage.
• Surface electrodes are less invasive but lack the resolution for precise neural targeting.
• Existing technologies struggle to balance invasiveness with high-resolution neural interfacing.

Purpose of the Study:

• To develop and characterize novel high-density, high-capacitance electrodes for precise neuromodulation.
• To demonstrate the capability of these electrodes for deep and lateral neural targeting.
• To integrate surface and depth electrodes with optical imaging for comprehensive neural communication studies.

Main Methods:

• Fabrication of high-density (40-μm pitch) PEDOT:PSS electrodes on a thin-film parylene substrate.
• Subdural implantation and chronic adherence to the pial surface.
• Combination of surface stimulation/recording with calcium imaging and depth recording in mouse visual cortex.

Main Results:

• Achieved single neuronal resolution with electrodes programmed for selective charge injection.
• Demonstrated precise targeting at depths up to 300 micrometers and lateral resolution better than 100 micrometers.
• Successfully combined surface and depth recording with optical imaging to map neural communication limits.

Conclusions:

• High-density PEDOT:PSS electrodes enable minimally invasive, high-resolution neuromodulation.
• These electrodes can achieve precise bidirectional communication with neurons at significant depths and lateral extents.
• The developed technology advances the potential for targeted neural therapies and research.