ABSTRACT

In principle, electrical currents have been applied to modulate cerebral functions for several hundred years (for a review see Zaghi et al. 2010a). In these early times, the main interest of researchers was to induce observable effects, such as limb movements, changes in perception, or reduction of clinical symptoms in patients (Hellwag and Jacobi 1802) using electrical stimulation, which, secondarily, led to neuronal activation. The stimulation techniques discussed in this chapter re–ne some of these early attempts with much better evaluation methods. Because they aimed primarily

4.1 Introduction ....................................................................................................93 4.2 tDCS ...............................................................................................................94