The physiological mechanisms underlying the effects of tRNS are not well known, however many hypotheses have been suggested. The robust changes in cortical excitability observed after tRNS could be attributed to the repeated opening of sodium channels and changes in their kinetics of activation and inactivation (Remedios et al. 2019 Effects of Short-Term<unk><unk>  Electrical Stimulation on Dissociated Pyramidal Neurons from the Cerebral Cortex. Neuroscience. 404:371-386. https://doi.org/10.1016/j.neuroscience.2019.01.035) or to the increased sensitivity of neuronal networks to modulation. tRNS may influence cortical oscillations, leading to changes in excitability. These proposed mechanisms are consistent with the observation that reversing electrode polarities in tRNS does not interfere with the augmentation in cortical excitability, suggesting that tRNS-induced cortical excitability is independent of current flow direction. Since tRNS is a repetitive,<unk> , and subthreshold stimulation, it is speculated that tRNS induces direct temporal summation of neural activity because the time constant of a neuron is sufficiently long to permit the summation of two stimuli presented in close succession. The effects of tRNS may also be explained in the context of the stochastic resonance phenomenon. tRNS is, by definition, a stimulation that induces non-finalized<unk>  activity in the system (i.e.,<unk> . The presence of neuronal<unk>  might enhance the sensitivity of the neurons to a given range of weak inputs (Huidobro et al., 2018 Optogenetic<unk> -photostimulation on the brain increases somatosensory spike firing responses. Neurosci Lett. 664:51-57.https://doi.org/10.1016/j.neulet.2017.11.004)
Transcranial random noise stimulation
Transcranial direct-current stimulation
Auditory brainstem implant
Transcranial magnetic stimulation
Electric acoustic stimulation
Non-invasive cerebellar stimulation
Magnetic seizure therapy
Electrical brain stimulation