New Book Chapter in Transcranial Brain Stimulation

New book chapter (Cellular and Network Effects of Transcranial Direct Current Stimulation: Insights from Animal Models and Brain Slice) in Transcranial Brain Stimulation by Professor Marom Bikson, Davide Reato, and Asif Rahman provides insights into the mechanisms of transcranial brain stimulation from the cellular effects of electrical stimulation in animal models and brain slices. This chapter addresses the contribution of animal research on direct current (DC) stimulation to current understanding of transcranial direct current stimulation (tDCS) mechanisms and prospects and pitfalls for ongoing translational research. Though we attempt to put in perspective key experiments in animals from the 1960s to the present, our goal is not an exhaustive cataloging of relevant animal studies, but rather to put them in the context of ongoing effort to improve tDCS. Similarly, though we point out essential features of meaningful animal studies, we refer readers to original work for methodological details. Though tDCS produces specific clinical neurophysiological changes and is therapeutically promising, fundamental questions remain about the mechanisms of tDCS and on the optimization of dose. As a result, a majority of clinical studies using tDCS employ a simplistic dose strategy where “excitability” is increased or decreased under the anode and cathode respectively. We discuss how this strategy, itself based on classic animal studies, may not account for the complexity of normal and pathological brain function, and how recent studies have already indicated more sophisticated approaches.