Balanced bifrontal transcranial direct current stimulation enhances working memory in adults with high-functioning autism: a sham-controlled crossover study.

Only 12 adults were studied, and the authors state the sample size was suboptimal for power. The study used a single stimulation session, so it does not show whether repeated tDCS produces lasting effects. Ceiling effects may have obscured benefit: BTA scores approached the maximum, and some participants had high n-back accuracy even at 2-back and 3-back. Participants were not told condition, but technicians knew it. Two participants had only 24 hours between sessions, and the authors say intervals should ideally be at least 1 week to avoid carryover. The tasks were laboratory working memory tests. The authors say future work should test transfer to applied cognitive and social skills.

The article lists funding from the Therapeutic Cognitive Neuroscience Fund, the Therapeutic Cognitive Neuroscience Endowment, and the Adith and Benjamin Miller Endowment for Autism, Aging, and Alzheimer’s Disease. No additional conflict-of-interest statement is reported.

Do not conclude that tDCS improves everyday communication or is ready for clinical use. The study tested laboratory working memory in 12 adults, and the authors call it a pilot. Further studies are needed.