Transcranial direct current stimulation-efficacy in mild cognitive impairment: A meta-analysis

Area of Science:

• Neuroscience
• Cognitive Science

Background:

• Mild cognitive impairment (MCI) represents a transitional stage between normal aging and dementia, carrying an elevated risk of progression.
• Early interventions for MCI are crucial for potentially preventing or delaying dementia onset.
• Non-invasive brain stimulation techniques, particularly transcranial direct current stimulation (tDCS), are being explored for cognitive enhancement in MCI.

Purpose of the Study:

• To systematically review existing evidence on the use of tDCS for individuals with MCI.
• To conduct a meta-analysis to assess the efficacy of tDCS in improving cognitive function in MCI patients.

Main Methods:

• Inclusion of eight single- or double-blinded randomized controlled trials.
• Assessment of global cognition using Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE).
• Evaluation of specific cognitive domains including digit span tests, Trail-Making Test (TMT) A and B, and Logical Memory Test (LMT), analyzed using a random-effects model with standardized mean difference (SMD).

Main Results:

• Active tDCS showed statistically insignificant effects on MoCA (SMD 0.37), MMSE (SMD 0.26), TMT-A (SMD -0.01), and LMT (SMD 0.80) compared to sham tDCS.
• Confidence intervals for all cognitive measures included zero, indicating no significant treatment effect.

Conclusions:

• The meta-analysis concluded that active tDCS treatment did not yield significant improvements in cognitive performance compared to sham tDCS in individuals with MCI.
• Current evidence suggests tDCS is not an effective intervention for cognitive enhancement in the MCI population based on this analysis.