Anodal Transcranial Direct Current Stimulation Promotes Frontal Compensatory Mechanisms in Healthy Elderly Subjects

• Published in: Frontiers in aging neuroscience Vol. 9; p. 420
• Main Authors: Cespón, Jesús, Rodella, Claudia, Rossini, Paolo M., Miniussi, Carlo, Pellicciari, Maria C.
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 18.12.2017; Frontiers Media S.A
• Subjects: Aging; Cognition & reasoning; compensatory mechanisms; EEG; Electrical stimulation of the brain; ESB; Event-related potentials; Geriatrics; Intelligence tests; Memory; Mental task performance; Neuroscience; P300; Prefrontal cortex; Short term memory; Systematic review; transcranial direct current stimulation; working memory; Italy; compensatory mechanisms; aging; event-related potentials; working memory; P300; transcranial direct current stimulation
• ISSN: 1663-4365; 1663-4365
• DOI: 10.3389/fnagi.2017.00420

Recent studies have demonstrated that transcranial direct current stimulation (tDCS) is potentially useful to improve working memory. In the present study, young and elderly subjects performed a working memory task ( -back task) during an electroencephalogram recording before and after receiving anodal, cathodal, and sham tDCS over the left dorsolateral prefrontal cortex (DLPFC). We investigated modulations of behavioral performance and electrophysiological correlates of working memory processes (frontal and parietal P300 event-related potentials). A strong tendency to modulated working memory performance was observed after the application of tDCS. In detail, young, but not elderly, subjects benefited from additional practice in the absence of real tDCS, as indicated by their more accurate responses after sham tDCS. The cathodal tDCS had no effect in any group of participants. Importantly, anodal tDCS improved accuracy in elderly. Moreover, increased accuracy after anodal tDCS was correlated with a larger frontal P300 amplitude. These findings suggest that, in elderly subjects, improved working memory after anodal tDCS applied over the left DLPFC may be related to the promotion of frontal compensatory mechanisms, which are related to attentional processes.