A flexible implantable microelectrode array for recording electrocorticography signals from rodents.

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Electrocorticography (ECoG) involves recording brain's electrical activity via surface electrodes.
• Non-penetrating flexible electrode arrays offer reduced tissue damage compared to rigid designs.
• Developing advanced ECoG tools is crucial for understanding neurological disorders.

Purpose of the Study:

• To design and develop a 32-channel flexible microelectrode array for ECoG signal acquisition in rats.
• To evaluate the array's capability in recording baseline brain activity, induced epileptic seizures, and drug-induced recovery.
• To analyze the spatiotemporal characteristics of brain signals using time-frequency analysis.

Main Methods:

• Fabrication of a flexible microelectrode array on a polyimide substrate with Ti/Au electrodes.
• Surgical implantation of the array onto the rat's somatosensory cortex.
• ECoG signal recording using OpenBCI Cyton Daisy Biosensing Boards.
• Induction of epileptic activity with a convulsant and subsequent administration of an antiepileptic drug.

Main Results:

• The flexible array successfully recorded baseline ECoG signals in anesthetized rats.
• The array captured induced epileptic discharges and the recovery of baseline signals post-antiepileptic drug administration.
• Time-frequency analysis revealed distinct spatiotemporal features between baseline and epileptic activity.

Conclusions:

• The developed 32-channel flexible microelectrode array is effective for ECoG signal recording in rats.
• The array demonstrates potential as a tool for monitoring epilepsy-related electrical brain signatures.
• The findings highlight the utility of flexible ECoG arrays in preclinical neurological research.