A new high-density (25 electrodes/mm²) penetrating microelectrode array for recording and stimulating sub-millimeter...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Electrophysiology

Background:

• Current neural interface devices lack sufficient electrode density for studying small neuroanatomical structures.
• There is a need for penetrating electrode arrays with high electrode count and density (electrodes/mm²).

Purpose of the Study:

• To develop and evaluate a high-density (25 electrodes/mm²) penetrating microelectrode array with up to 96 electrodes.
• To assess the safety and efficacy of this array for electrophysiological studies in small nervous system structures.

Main Methods:

• Development of a high-density microelectrode array based on the Utah Slanted Electrode Array (USEA).
• Acute in vivo experiments involving implantation into peripheral nerves (rat sciatic, cat pudendal) of anesthetized animals.
• Evaluation of implantation safety through microstimulation, single-unit recordings, histological analysis, and impedance measurements.

Main Results:

• Successful intrafascicular implantation of the high-density microelectrode array was achieved.
• Viable nerve function was maintained post-implantation, as evidenced by electrophysiological and histological data.
• The array demonstrated fabrication quality and facilitated intrafascicular access to nerve fibers without causing complete crush injury.

Conclusions:

• The developed high-density penetrating microelectrode array provides unmatched characteristics for peripheral nervous system neurophysiological research.
• This novel neural interface enables detailed electrophysiological studies of small neural structures.
• The array represents a significant advancement in neural interface technology for neuroscience research.