Modulatory mechanisms underlying high-frequency transcranial random noise stimulation (hf-tRNS): A combined stochastic resonance and equivalent noise approach.

摘要: Abstract Background High-frequency transcranial random noise stimulation (hf-tRNS) is a neuromodulatory technique consisting of the application alternating current at intensities and frequencies. hf-tRNS induces neural activity in system that may boost sensitivity neurons to weak inputs. Stochastic resonance nonlinear phenomenon whereby addition an optimal amount results performance enhancement, whereas further increments impair signal detection or discrimination. Objective The aim study was assess whether modulatory effects rely on stochastic phenomenon, what specific mechanism producing resonance. Method Observers performed two-interval forced choice motion direction discrimination task which they had report two moving patches presented temporal intervals same different directions. administered five intensity levels (0.5, 0.75, 1.0, 1.5, 2.25 mA). Results showed significant improvement when applied 1.5 mA, representing level external noise. However, 2.25 mA significantly impaired performance. An equivalent (EN) analysis, used how modulates mechanisms underlying global processing, increment integration with intensity, but reduced 2.25 mA. Conclusion These indicate hf-tRNS-induced signal-to-noise ratio way compatible phenomenon.