Attentional modulation of neural phase is enhanced by short-term training and linked to musical experience

Abstract

How does the brain follow a sound that is mixed with others in a noisy environment? A possible strategy is to allocate attention to task-relevant time intervals while suppressing irrelevant intervals -a strategy that could be implemented by aligning neural modulations with critical moments in time. Here we tested whether selective attention to non-verbal sound streams is linked to shifts in the timing of attentional modulations of EEG activity, and investigated whether this neural mechanism can be enhanced by short-term training and musical experience. Participants performed a memory task on a target auditory stream presented at 4 Hz while ignoring a distractor auditory stream also presented at 4 Hz, but with a 180-degree shift in phase. The two attention conditions were linked to a roughly 180-degree shift in phase in the EEG signal at 4 Hz. Moreover, there was a strong relationship between performance on the 1-back task and the timing of the EEG modulation with respect to the attended band. EEG modulation timing was also enhanced after several days of training on the selective attention task and enhanced in experienced musicians. These results support the hypothesis that modulation of neural timing facilitates attention to particular moments in time and indicate that phase timing is a robust and reliable marker of individual differences in auditory attention. Moreover, these results suggest that nonverbal selective attention can be enhanced in the short term by only a few hours of practice and in the long term by years of musical training.