The improvement in working memory accuracy for older adults was observed to outlast the stimulation period and continue to the last measurable post-stimulation time point in Experiments 1 and 2, raising the possibility that subjects experienced improvements in working memory function that lasted longer than what could be evaluated in the present study. Future research will be important to determine the full time course of the stimulation-induced behavioral advantages and whether they can transfer to other working memory functions (e.g., capacity, updating, switching) and higher-order cognitive abilities that rely on working memory, such as language comprehension, mathematical competence, and decision-making. Research efforts in this direction should help set the groundwork necessary for developing future non-pharmacological interventions aimed at reducing cognitive deficits in physiological aging and clinical populations.
