Flexible deep brain neural probe for localized stimulation and detection with metal guide

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Precise neural stimulation and recording in deep brain structures are crucial for understanding and treating neurological disorders.
• Existing neural probes can cause significant tissue damage and immune responses, limiting their long-term efficacy.
• Flexible, minimally invasive probes are needed to overcome these limitations.

Purpose of the Study:

• To design, fabricate, and evaluate a polyimide-based flexible neural probe for precise deep brain stimulation and recording.
• To assess the probe's biocompatibility and minimize tissue damage.
• To validate the probe's performance in vivo.

Main Methods:

• Fabrication of a polyimide-based flexible neural probe with five electrodes (stimulation, ground, recording).
• Design incorporates a foldable structure for insertion using guide sticks.
• Performance evaluation using finite element analysis, in vitro tests, and in vivo animal experiments (rats).

Main Results:

• The flexible probe demonstrated minimal neural tissue damage and no significant immune reactions.
• An integrated ground electrode reduced stimulation power leakage by approximately 80%.
• Successful recording of neural spike signals from the subthalamic nucleus (STh) in rats at a 7mm depth.

Conclusions:

• The polyimide-based flexible neural probe offers a promising solution for precise deep brain stimulation and recording.
• Its design minimizes invasiveness and associated immune responses.
• The probe is effective for in vivo neural signal acquisition in deep brain structures.