Neural hijacking: action of high-frequency electrical stimulation on cortical circuits

Area of Science:

• Neuroscience
• Neurophysiology
• Biophysics

Background:

• Electrical brain stimulation is a foundational research and clinical tool.
• Intracortical microstimulation (ICMS) uses microelectrodes to stimulate single neurons.
• Understanding neural activation mechanisms is critical for therapeutic applications.

Purpose of the Study:

• To investigate the mechanism of neural activation by high-frequency electrical stimulation.
• To explain the phenomenon of "neural hijacking" observed during stimulation.
• To link neural hijacking to the efficacy of deep brain stimulation in Parkinson's disease.

Main Methods:

• Review of recent experimental results on cortical neuron responses to ICMS.
• Analysis of neural activity patterns during high-frequency stimulation.
• Examination of evidence from deep brain stimulation studies.

Main Results:

• High-frequency ICMS does not sum with natural neural activity; it replaces it, termed "neural hijacking."
• Neural hijacking involves axon excitation and antidromic collision of spikes.
• This mechanism is implicated in the therapeutic effects of subthalamic nucleus deep brain stimulation for Parkinson's disease.

Conclusions:

• High-frequency electrical brain stimulation operates via neural hijacking.
• Axonal excitation and spike collision are proposed mechanisms for neural hijacking.
• Neural hijacking provides insight into deep brain stimulation efficacy for neurodegenerative disorders.