Micro-Coil Neuromodulation at Single-Cell and Circuit Levels for Inhibiting Natural Neuroactivity, Neutralizing...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Neural Engineering

Background:

• Neuromodulation techniques are crucial for understanding and treating neurological disorders.
• Current neural interfaces have limited options for precise neural inhibition.
• Developing targeted methods for suppressing neural activity is essential for therapeutic interventions.

Purpose of the Study:

• To present a microchip-based implantable device for precise cortical inhibition using micromagnetic stimulation (µMS).
• To investigate the efficacy of µMS in suppressing neural activity in vivo.
• To compare µMS with micro-electrode stimulation (µES) and evaluate its potential for treating hyperactivity.

Main Methods:

• Development of a microchip-based implantable micro-coil device for µMS.
• In vivo two-photon imaging of spontaneous neural activity in the cortex.
• Application of varying magnitudes of µMS and concurrent µES.
• Pharmacological induction of seizures to assess seizure mitigation.

Main Results:

• µMS reversibly suppressed single cortical cells, with increased magnitude suppressing up to 41% of cells.
• µMS achieved a highly localized effect (0.05 mm²), seven times smaller than µES.
• Neurons exhibited stronger responses to µMS than µES, enabling neutralization of µES-induced excitation.
• µMS reduced seizure amplitude by 54% in a pharmacologically induced seizure model.

Conclusions:

• µMS is a precise, effective, and versatile tool for localized neuromodulation with inhibitory effects.
• µMS offers an inhibitory polarity opposite to µES, complementing existing stimulation methods.
• µMS shows significant promise as a neuroscience research tool and a potential therapeutic for hyperactive brain circuits.