Feasibility and tolerability of combining 6 Hz transcranial alternating current stimulation (tACS) at 3.2 mA and digital cognitive training in older adults with mild cognitive impairment.

In 30 seconds

This randomized-trial study evaluated feasibility and tolerability of five daily sessions of 6-Hz, 3.2-mA transcranial alternating current stimulation (tACS) during digital cognitive training (DCT) in older adults with mild cognitive impairment, with exploratory comparisons against a sham group. All participants completed treatment (100% adherence); active-session side effects were mild in 67% and moderate in 23%, with no severe events. Antisaccade errors showed a group-by-time interaction favoring active stimulation (p = 0.028), while reaction time showed no stimulation-specific effect. The authors conclude that the approach was feasible and well tolerated, but efficacy findings require confirmation.

Key findings

• All participants completed treatment, with 100% adherence.
• During active sessions, side effects were mild in 67% and moderate in 23%; no severe events occurred.
• Antisaccade total errors showed a group × time interaction favoring active stimulation (p = 0.028); reaction time had no stimulation-specific effect.
• Verbal and visual memory showed time effects (p = 0.016 and p = 0.002); visuoconstructive abilities had a trend-level group × time interaction (p = 0.054).

Why it matters

Higher-intensity tACS delivered alongside cognitive training was completed by participants with mild cognitive impairment without severe reported events. The exploratory inhibitory-control result and possible transfer to selected cognitive domains provide a rationale for further evaluation, while the absence of a reaction-time effect and the need for confirmation temper conclusions about cognitive benefit.

What to keep in mind

The active group included ten participants, and efficacy analyses were exploratory. The abstract states that confirmation in the ongoing randomized controlled trial is warranted.