Evidence of Neuroplastic Changes after Transcranial Magnetic, Electric, and Deep Brain Stimulation

Abstract

Electric and magnetic stimulation of the human brain can be used to excite or inhibit neurons. Numerous methods have been designed over the years for this purpose with various advantages and disadvantages that are the topic of this review. Deep brain stimulation (DBS) is the most direct and focal application of electric impulses to brain tissue. Electrodes are placed in the brain in order to modulate neural activity and to correct parameters of pathological oscillation in brain circuits such as their amplitude or frequency. Transcranial magnetic stimulation (TMS) is a non-invasive alternative with the stimulator generating a magnetic field in a coil over the scalp that induces an electric field in the brain which, in turn, interacts with ongoing brain activity. Depending upon stimulation parameters, excitation and inhibition can be achieved. Transcranial electric stimulation (tES) applies electric fields to the scalp that spread along the skull in order to reach the brain, thus, limiting current strength to avoid skin sensations and cranial muscle pain. Therefore, tES can only modulate brain activity and is considered subthreshold, i.e., it does not directly elicit neuronal action potentials. In this review, we collect hints for neuroplastic changes such as modulation of behavior, the electric activity of the brain, or the evolution of clinical signs and symptoms in response to stimulation. Possible mechanisms are discussed, and future paradigms are suggested.

Challenging the Pleiotropic Effects of Repetitive Transcranial Magnetic Stimulation in Geriatric Depression: A Multimodal Case Series Study

“…MEP: motor evoked potential. Modified from [ 77 ]. MEP: motor evoked potential; rTMS: repetitive transcranial magnetic stimulation.…”

Brain Stimulation and Neuroplasticity—Series II

“…Finally, Kricheldorff et al [ 9 ] present a narrative review on the possibilities of different brain stimulation techniques, i.e., magnetic, electrical, and deep brain stimulation, to modulate cortical neuroplasticity (i.e., MEP, EEG, magnetoencephalography outcomes) and clinical as well as behavioral outcomes. They elegantly tackle the mechanisms of action of these techniques and suggest future paradigms to pave the way for forthcoming research.…”

Effect of transcranial direct current stimulation combined with pelvic muscle training in women: Randomized, controlled, double‐blind, and clinical trial

“…6 In the last two decades, it has become an instrument to investigate the cortical neural plasticity mechanisms and motor learning, given its capacity for prolonged changes in brain excitability, even after the stimulation period has ended. 7 Moreover, recent studies have shown that associating tDCS with other therapies may favor longer-lasting effects than when the therapy is executed alone. 8 Thus, the hypothesis of the study is that the tDCS associated with TMAP can enhance and prolong the effects of training alone.…”