The second edge of ADHD: an advantage in motor learning and performance with task-irrelevant background vibratory noise

Young adults with ADHD often gain less than expected from practice sessions well-suited for their peers. Here, we tested whether task-irrelevant, low-intensity vibratory stimulation (VtSt), suggested to modulate motor learning, may compensate for such learning deficits. Participants were given training, either with or without VtSt, on a sequence of finger opposition movements. Under VtSt, typical individuals had reduced overnight, consolidation phase, gains; performance partly recovering one week later. In contrast, participants with ADHD benefitted from VtSt both during the acquisition (online) and the overnight skill consolidation (offline) phases. One week later, both groups showed robust retention of the gains in performance, but when tested with background VtSt, individuals with ADHD outperformed their typical peers. We propose that ADHD can confer advantages in performance, learning and skill memory consolidation in specific noisy conditions that adversely affect typical adults; we conjecture that the effects of VtSt are contingent on baseline arousal levels.