White noise has more ADHD-specific research than any other sound type. The foundational study by Soderlund, Sikstrom, and Smart (2007) found that white noise improved cognitive performance in children with ADHD while deteriorating performance in typically developing controls. This introduced the Moderate Brain Arousal (MBA) model, which explains the effect through stochastic resonance and dopamine-modulated neural noise thresholds.
A 2024 meta-analysis by Nigg et al. reviewed 13 studies covering 335 ADHD participants and 335 controls. The ADHD group showed a small but statistically significant benefit (g = 0.249, p < 0.0001). The non-ADHD group showed the opposite effect (g = -0.212, p = 0.004). These effects were statistically different from each other. GRADE certainty was rated Moderate (downgraded only because participants cannot be blinded to noise).
Additional supporting studies include Soderlund et al. (2010), which found white noise at 78 dB enhanced memory recall in inattentive children (F=9.96, p=.003), and Lin (2022), where 104 preschoolers in a randomized crossover design showed ADHD children improving on 7 of 11 indicators to typically-developing ranges.
A 2024 study by Soderlund et al. found that children with higher inattention scores benefited from noise, while those with elevated hyperactivity/impulsivity scores performed worse. This suggests the benefit is specific to the inattentive presentation of ADHD.
A note on labeling
Most consumer "white noise" products actually produce grey noise, a perceptually shaped variant. True white noise has a flat power spectral density (equal energy at every frequency), which sounds bright and harsh. During Ebbi's development, we discovered this discrepancy and built both true white noise and grey noise so users can hear the actual difference and choose what works for their brain.