“…While the neuromodulatory after-effects induced by NIBS techniques (including tDCS) appear to be relatively stable over prolonged time courses (López-Alonso et al, 2015), the nature and magnitude of these effects varies considerably between individuals (Hamada, Murase, Hasan, Balaratnam, & Rothwell, 2013;Nettekoven et al, 2015;Nitsche & Paulus, 2001;Wiethoff, Hamada, & Rothwell, 2014). One source of this variability may be the brain statedependent nature of these effects, meaning that the history of endogenous activity of one region may be crucial to the effects of brain stimulation (Silvanto, Cattaneo, Battelli, & Pascual-Leone, 2008) and consequent activation of homeostatic and non-homeostatic metaplasticity mechanisms (Amadi et al, 2015;Muller-Dahlhaus & Ziemann, 2015).…”