Proof of Beat Entrainment and its Characteristics

Youmin Shin, June Sic Kim, Chun Kee Chung

Abstract: Beat entrainment, an active synchronization between endogenous neural oscillations and rhythm stimuli, is a key element in various research fields, including attention selection, sensorimotor synchronization, speech and music. Various studies are under way on the beat entrainment, but it is still being discussed whether this brain response only reflects regular repetition of the events, or it includes entrained oscillatory activities. Nor is the mechanism and functional role of the beat entrainment known. The purpose of our study is to present evidence that the beat oscillation is inherently formed and to propose the functions and mechanisms of beat entrainment. The experiment was conducted in a sequence with 700ms of regular sound stimulus that had an amplitude cycle of `strong, weak, weak', containing some irregularly missing stimuli. Brain signal was measured using electrocorticography for epilepsy disease patients. As a result, significant neural oscillations were formed compared to the pre-stimulus section. Oscillations consist of 1.4286Hz oscillation dependent on all stimuli, as well as 0.4762Hz oscillation dependent only on strong stimuli. This demonstrate that the beat is characterized by its formation with weighting certain rhythm. The latencies of the response in each stimulus was identified differently. this can be evidence that beat entrainment is a procedure of endogenous brain response. And we suggest beat entrainment mechanism used to readjustment of beat entrainment and how brain percept different rhythm differently.