Noninvasive Brain Stimulation

11 Abstract. Noninvasive brain stimulation (NIBS) techniques such as transcranial 12 magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) have 13 recently attracted interest due to their potential for transiently improving cognitive 14 functions and memory in human beings. In aging, these techniques may prove 15 particularly valuable given the impact of age-related cognitive dysfunction on quality 16 of life. The present review summarizes the currently available evidence of working 17 and episodic memory enhancement achieved using NIBS in healthy elderly people. 18 The evidence reviewed indicates that research is still at an early stage and that there 19 is a need to define the best procedures for operating and performing multicenter 20 characterization of protocols. However, a limited number of sham-controlled studies 21 have reported improvements in both working memory and episodic memory domains 22 among healthy elders using NIBS. Furthermore, some studies have demonstrated the 23 long-term persistence of the positive effects, a finding that opens up the possibility of 24 using NIBS as an adjuvant therapeutic strategy in the management of age-associated 25 memory decline. However, the relevance of many of the variables involved and 26 approaches used remains to be elucidated, including the potential benefits of single 27 versus multiple NIBS sessions, the putative synergistic effects of using NIBS in 28 combination with cognitive training, and the importance of individual differences 29 between subjects. Overall, NIBS techniques represent a promising opportunity for 30 psychologists seeking strategies to improve memory functions in the elderly. 31 Nevertheless, their use requires appropriate technical knowledge coupled with a 32 clear understanding of the neurophysiology and cognitive neuroscience of aging. Only 33 by ensuring that these requirements are met can we refine our hypotheses and select 34 the best procedures for optimizing the effect of NIBS on cognition Q3 . 35