Induced neural phase precession through exogenous electric fields.

Area of Science:

• Neuroscience
• Computational Neuroscience
• Neural Coding

Background:

• Phase precession, the shift of neural spiking relative to local field potentials (LFPs), is implicated in neural coding and neuroplasticity.
• Existing research shows correlations between phase precession and behavior across brain regions.
• Causal evidence and underlying neuroplastic mechanisms for phase precession remain largely unexplored.

Purpose of the Study:

• To establish a causal link between LFP dynamics and phase precession.
• To investigate the neuroplastic mechanisms driving phase precession.
• To explore the potential of alternating current stimulation for therapeutic neuromodulation.

Main Methods:

• Modulation of LFPs using alternating current (AC) stimulation in humans, non-human primates, and computational models.
• Measurement of corticospinal excitability shifts in humans.
• Recording of neural activity and induction of phase precession in primates.
• Multiscale modeling of neural circuits to elucidate plasticity mechanisms.

Main Results:

• Continuous AC stimulation of human motor cortex oscillations induced a ~90° phase shift in maximal corticospinal excitability.
• Exogenous AC stimulation successfully induced phase precession in approximately 30% of entrained neurons in a non-human primate.
• Computational models indicated that AC stimulation-induced phase precession is driven by NMDA-receptor mediated synaptic plasticity.

Conclusions:

• The study provides mechanistic and causal evidence for phase precession as a global neocortical process.
• AC stimulation can induce phase precession and subsequent synaptic plasticity.
• These findings are crucial for developing novel therapeutic neuromodulation strategies.