研究発表

未知なる次の音楽（= x-Music）とは何か？ 音楽をテーマとした研究や表現の可能性が劇的に変化している今、我々人類は一体どのような音楽の研究・表現を行うべきでしょうか。藤井進也研究会 エクス・ミュージック・ラボ（x-Music Lab）では、多様な文化・芸術・学術領域を横断・乗算（= Crossing, ‘x’）させ、音楽の起源や普遍性、応用性を探究しています。また、まだ確固たる名称のない、未知なる次の音楽文化（= ne’x’t Music）を創造・開拓することを目的とし活動を行っています。

How people use auditory and visual information to judge musical performance? Contrary to the belief that audition should be more important than vision in the judgement of musical performance, the visual judgement was shown to be more accurate than audition (Tsay, PNAS, 2013; Mehr et al., PLoS ONE, 2018). In this study, we tested if the “sight-over-sound” effect was replicable when judging the performance in brass ensemble competition in Japan. Thirty-three people participated in this study (22.0 ± 4.29 years of age, 11 females). All participants had experience to play in a brass band (8.67 ± 4.40 years of experience) but had no experience as an instructor. The 93.9% of participants reported subjectively that sound should be more important than vision in the ensemble judgement. The participants were randomly assigned to one of the three judgement conditions: 1) Audio-only, 2) Visual-only and 3) Audio-Visual conditions (11 participants each). The one-way ANOVA showed no significant difference in the judgement accuracy among the three groups (F(2,30)=0.12, p=0.89). The one-sample t-tests revealed that the judgement accuracy was significantly higher than the chance level in the Audio-only condition and AudioVisual condition but not in Visual condition (40.0%, t(10)=2.85, p=0.02; 40.9%, t(10)=2.66, p=0.02; 38.2%, t(10)=0.83, p=0.43, respectively). Our results suggest that sight-over-sound effect is not replicable in the judgement of brass ensemble competition in Japan.

Music is known to evoke psychological pleasure and activate the reward-related regions of the brain. While multiple studies have shown that prediction error plays an important role in musical reward, a recent study by Cheung et al. (2019) pointed out the significance of not only surprise but also uncertainty resolution in music. Although early right anterior negativity (ERAN) is known to reflect surprise and syntactical errors (Koelsch, 2009), less is known about uncertainty resolution especially from an electroencephalographic (EEG) perspective. Therefore, we performed an experiment to explore the EEG activity related to uncertainty resolution in music. Participants listened to sound sequences; in the "standard" condition, four chords (I, IV, IIm7, and V7) were repeated four times, and in the "deviant" condition, the third chord (IIm7) in the fourth block was replaced with a deviant chord (IV#dim) to enhance uncertainty. The standard condition tended to be rated as more pleasant than the deviant condition, suggesting that resolving the uncertainty increased the pleasure. Although ERAN was not observed at the deviant chord (IV#dim), a negative component, similar to stimulus preceding negativity, was observed before the last dominant chord (V7) in the deviant condition. In addition, decrease of delta, beta, and gamma band power was observed at a close time window. We thus suggest that these activity, specifically the negative component and change in delta and beta power, might reflect the anticipation of uncertainty resolution.