Transcranial direct current stimulation for mild cognitive impairment

Abstract

Mild cognitive impairment (MCI) is recognized as a target for early intervention in elderly with high risk for dementia due to Alzheimer's disease (AD) and other related disorders. Transcranial direct current stimulation (tDCS) is reemerging as a novel method of noninvasive brain stimulation in various neuropsychiatric disorders including MCI and dementia based on the potential clinical applications of its utility in modulating neuroplasticity. In this article, we review the neurobiology of aging, AD, and MCI from the perspective of tDCS and summarize the findings from studies applying tDCS in MCI to improve cognitive function. Studies on therapeutic application of tDCS to improve cognitive function in MCI and other related disorders have shown mixed results. Limited studies available in this topic suggest a potential role for tDCS in MCI. Low risk for adverse effects, lower cost, and the possibility of self-administered home-based intervention are important advantages that encourage further research in this field. There is a need for more evidence from large systematic randomized controlled trials regarding the efficacy of tDCS in MCI. Standardization of stimulation protocols, evaluation of long-term outcome with the possibility of maintenance tDCS, and efficacy of combined intervention of tDCS and cognitive training are important areas for future research in this area.