Indentation response in porcine brain under electric fields

Area of Science:

• Neuroscience
• Biophysics
• Biomaterials

Background:

• Electric fields impact brain function and behavior, informing neuromodulation therapies like transcranial electrical stimulation (tES), deep brain stimulation (DBS), and electroconvulsive therapy (ECT).
• Existing research primarily focuses on the therapeutic effects of electrical fields, neglecting the mechanical properties of brain tissue under these conditions.

Purpose of the Study:

• To investigate the mechanical properties of brain tissue exposed to varying intensities of direct current electric fields.
• To characterize how electric fields influence the viscoelastic behavior of brain tissue.

Main Methods:

• Utilized a custom-designed indentation device to measure the mechanical properties of brain tissue under direct current electric fields (0–50 V).
• Performed validation tests on hydrogels to ensure no interference from the indentation device.
• Applied linear elastic and viscoelastic models to analyze indentation-relaxation test data.

Main Results:

• Brain tissue exhibited softening at higher electric field intensities.
• Increased electric field strength led to decreased tissue viscosity and faster response times.
• Analysis of resistance and thermal responses provided insights into the observed mechanical changes.

Conclusions:

• Direct current electric fields significantly alter the mechanical properties of brain tissue, causing softening and reduced viscosity.
• Understanding these mechanical responses is vital for a comprehensive understanding of neuromodulation therapy mechanisms.
• Findings can inform and optimize therapeutic protocols for neuropsychiatric disorders.