The activity of the brain can be measured in a number of ways. One of these is electroencephalography (EEG) which is the measurement of electrical potentials generated by neural activity. One type of phenomenon that can be measured with EEG is called neural oscillations, generated by the repetitive and rhythmic firing patterns of groups of neurons.
Recently, a paper reported three studies where it was shown that neural oscillations of subjects started to follow the rhythm of the music the subjects were listening to. This means that groups of neurons in their brains could “catch” the beat of the music, and synchronize their firing to it. This syncing of oscillations to external cues is called neural entrainment. According to the results of the study, the subjects’ brains entrained to the beat in musical pieces with different rhythms. However, entrainment did not occur to the beats in music that were below one beat per second, meaning a very slow beat. Entrainment was also relevant for music processing - the better the entrainment of brain oscillations to the beat, the better the subjects’ performance in a task for detecting pitch.
The researchers also investigated entrainment of neural oscillations to music in trained musicians and found something interesting: the musicians’ brains became entrained also to beats that were below one beat per second. Entrainment was also stronger in musicians with more years of practice, which may mean that music training broadens and enhances the brain’s capacity to sync to rhythms. However, longitudinal studies are needed to conclude whether music training or initial predispositions are the source of these observed augmentations in entrainment.
Why would the brain sync to the beat of the music you are listening to? The authors suggest that entrainment might help the brain package auditory information and thereby process it more efficiently. The results suggest that this packaging might be improved by music training and may help in the processing of many kinds of auditory stimuli. Study of how the brain processes music may therefore reveal important aspects of the processing of auditory information in general.
written by ketki karanam
Doelling, K. B., & Poeppel, D. (2015). Cortical entrainment to music and its modulation by expertise. Proc Natl Acad Sci USA, 112(45), E6233–E6242. doi:10.1073/pnas.1508431112