Musicians and non-musicians’ dissonance/consonance perception: separate and joint analyses of event-related potential (ERP) and functional Magnetic Resonance Imaging (fMRI) experiments of the same design

Abstract

Musician’s sensibility of detecting a tonal difference between two musical notes is extraordinary The perception of musical tonality can be either consonant or dissonant depending on pitch relationship between intervals Previous studies suggested that musician and nonmusician may have different reliance upon discerning two intervals from the perspective of frequency ratio (Western tonal theory) or the frequency difference (psychoacoustics) In this study electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) are used with jittered event-related design to obtain a finer brain activity in response to tonal dissonance/consonance Thirty-two musicians and thirty nonmusicians judged dissonance and consonance at 20 sounds of pitch interval and roughness orthogonally mixed across frequency range from 100Hz to 500Hz for behavioral The fifteen musicians and fourteen nonmusicians results are collected for EEG experiments and fourteen musicians and seventeen nonmusicians for fMRI experiments Behavior findings supported previous evidence for an association between musician with pitch interval and nonmusician with roughness the EEG results further demonstrated that manipulation of tonal differences increased interaction effect between groups and frequency interval at N1 amplitude across the midline FZ FCZ CZ and CPZ channels The fMRI results using ANOVA and MVPA searchlight also indicated the functional dissociations between musicians and non-musicians in the frontal lobe including Medial Prefrontal Cortex (MPFC) Medial Frontal Gyrus (MFG) Superior Frontal Gyrus (SFG) and in the temporal lobe such as primary auditory cortex Furthermore the representational similarity analysis (RSA) was used to identify spatio-temporally corresponding brain regions for dissimilarity matrix designed on different frequency properties across stimuli and 12-channels ERP postulating top-down driven consonance/dissonance judgments processing in musicians and bottom-up processing for non-musicians Together these results suggest that musicians and non-musicians rely upon pitch intervals and sensory roughness respectively for consonance/dissonance perception To our knowledge this is the first study to combine multi-modal data across the pitch interval and roughness spectrum Our results further support the brain plasticity as a result of musical training in consonance perception

Date of Award	2020
Original language	English
Supervisor	Sheng-Fu Liang (Supervisor)