Prolonged exposure to highly rhythmic music affects brain dynamics and perception

Abstract

Rhythmic stimulation is a powerful tool to improve temporal prediction and parsing of the auditory signal. However, for long duration of stimulation, the rhythmic and repetitive aspects of music have often been associated to a trance state. In this study we conceived an auditory monitoring task that allows tracking changes of psychophysical auditory thresholds. Participants performed the task while listening to rhythmically regular and an irregular (scrambled but spectrally identical) music that were presented with an intermittent (short) and continuous (long) type of stimulation. Results show that psychophysical auditory thresholds increase following a Continuous versus Intermittent stimulation and this is accompanied by a reduction of the amplitude of two event-related potentials to target stimuli. These effects are larger with regular music, thus do not simply derive from the duration of stimulation. Interestingly, they seem to be related to a frequency selective neural coupling as well as an increase of network connectivity in the alpha band between frontal and central regions. Our study shows that the idea that rhythmic presentation of sensory stimuli facilitates perception might be limited to short streams, while long, highly regular, repetitive and strongly engaging streams may have an opposite perceptual impact.

Short-Term Effect of Auditory Stimulation on Neural Activities: A Scoping Review of Longitudinal Electroencephalography and Magnetoencephalography Studies

“…With increasing sound intensity, the latency of auditory brainstem responses was shortened and their amplitude enhanced [96]. In addition, cortical excitation patterns expanded with increasing sound intensity (for Nd and P300: [106]; for N1-P2: [107]). The early gamma-band responses also increased with increasing sound pressure, accompanied by an increase in intertrial phase-locking, which was more prominent in the active vs. passive condition [107].…”