A parametric investigation of binaural beats for brain entrainment and enhancing sustained attention.

Binaural beats (BBs) have garnered attention as a highly accessible, noninvasive method to enhance cognitive performance, putatively via brain entrainment. However, the few studies that have directly examined the impact of BBs on sustained attention report inconsistent findings, perhaps due to wide variation in methodology. This study experimentally varied BB parameters while testing the effects of BBs on both sustained attention and brain entrainment. 80 undergraduate participants were randomized to 1 of 16 between-subject conditions in a 2 beats frequency (beta or gamma) × 2 carrier tone (340 or 400 Hz) × 2 onset time (before or with task onset) × 2 background masking noise (present or absent) factorial design. Participants completed a 2-visit within-subjects cross-over comparison of BBs vs. control auditory stimulation. EEG data were collected to validate brain entrainment. Gamma frequency BBs with a low carrier tone and white noise background improved general attention performance but did not reduce the vigilance decrement over time, suggesting BBs may modulate other cognitive aspects rather than sustained focus. EEG results confirmed brain entrainment, though entrainment varied with BB parameters and background noise. Further research should explore the interactions between BB parameters to optimize their use for cognitive enhancement.