雅樂效應思維：〈樂記〉身心審美的當代解讀

此書見解獨到，論點精闢，從音樂理論角度，以腦科學研究方法，詮釋雅樂的全新風貌。足見作者用心之深，研究之嚴謹，是值得一讀再讀的好書

這本書提到一項腦造影實驗，該實驗在台大進行，我亦有所耳聞。《雅樂效應思維》第47頁提到，此實驗的受試者有31位，一半的受試者聽韓國傳統雅樂，另一半聽莫札特音樂，結果發現在聆聽音樂之後，聽韓國傳統雅樂這組人的背外側前額葉與背側前扣帶回、背外側前額葉之功能性連結增加，另一組人則無此現象，然後，

"為了更進一步確定此腦部活動情形與正念狀態是否有關，研究團隊又進行了一個心理作業測驗的實驗，用測量正念狀態以及思緒漫遊（mind wondering）程度的測驗SART，測試聆聽後的心智運作情形是否較為接近正念狀？實驗結果也是肯定的。" (《雅樂效應思維》P. 47)

這些敘述，至少暴露出三個問題。第一，思緒漫遊這個概念首度出現於這本書的時候，王育雯老師似乎沒有為它下定義。第二，思緒漫遊的英文寫錯了，不是mind wondering，而是mind wandering。第三，這項腦造影研究並未發表於國際學術期刊，王育雯老師在這段敘述所給出的文獻，乃是國際研討會論文［Wang, Y., Teng, S.-C., Lien, Y.-W., Huang, Y.-A., & Chen, J.-H.(2014). Music Induces Mindfulness State — The Sujecheon Effect. Proceedings of the Third Joint Conference of ICMPC］，我也參與了該次研討會，水準不錯，但是研討會論文畢竟不是什麼正式的論文。
《雅樂效應思維》第99頁提到一篇重要論文［Juslin PN1, Västfjäll D. (2008). Emotional responses to music: the need to consider underlying mechanisms. Behav Brain Sci. 31(5):559-75; discussion 575-621.］，該文探討音樂引發情緒的機制。我也曾撰文探討這篇重要論文，因為該文在發表後十年之間，被引用的次數超過1400次，詳見拙文。令人遺憾的是，《雅樂效應思維》第99頁的敘述，似有誤導之嫌，糟蹋了原本的英文論文：

"腦幹反應則涉及個體的身心特質。而音樂情緒感染、視覺想像、聆聽過程中的期待等，不僅牽涉到主體的情緒、想像、認知等心理活動、以及與此相伴之個人心理特質，同時也牽涉到聲響風格結構。"

這些敘述，至少暴露出三個問題。第一，腦幹反應這個詞是錯誤的中文翻譯，原文brain stem reflex，應該翻譯為腦幹反射。生理學中的反射一詞，強調的是針對特定的刺激產生快速反應，跟一般的反應並不相同，Encyclopaedia Britannica 指出”Reflex, in biology, an action consisting of comparatively simple segments of behaviour that usually occur as direct and immediate responses to particular stimuli uniquely correlated with them.” 第二，跟音樂引起情緒的其他機制相比，brain stem reflex比較不涉及個體特質，因為腦幹是比較“hard-wired”的低階腦區。第三，跟音樂引起情緒的其他機制相比，brain stem reflex應該更加牽涉到聲響風格結構，具體而言，容易造成腦幹反射的聲響，乃是突然出現的巨響或不協和音。為了還原brain stem reflex的本質，以下引用Juslin & Västfjäll (2008) 文中的相關敘述，並加上註解。

3.1.1. Brain stem reflex. This refers to a process whereby an emotion is induced by music because one or more fundamental acoustical characteristics of the music are taken by the brain stem to signal a potentially important and urgent event. All other things being equal, sounds that are sudden, loud, dissonant, or feature fast temporal patterns induce arousal or feelings of unpleasantness in listeners ［按：這裡指出哪些特定聲響容易誘發腦幹反射］ (e.g., Berlyne 1971; Burt et al. 1995; Foss et al. 1989; Halpern et al. 1986). Such responses reflect the impact of auditory sensations – music as sound in the most basic sense. The perceptual system is constantly scanning the immediate environment in order to discover potentially important changes or events. Certain sound qualities are indicative of change, such as sudden or extreme sounds, sounds that change very quickly, or sounds that are the result of strong force or large size. Sounds that meet certain criteria (e.g., fast, loud, noisy, very low- or high-frequenced) will therefore produce an increased activation of the central nervous system. The precise physiological processes underlying such brain stem responses are not completely understood, although evidence suggests that they occur in close connection with the reticular formation of the brain stem and the intralaminar nuclei of the thalamus, which receive inputs from the auditory system. The brain stem is an ancient structure of the brain that subserves a number of sensory and motor functions including, but not limited to, auditory perception and the mediation and control of attention, emotional arousal, heart rate, breathing, and movement (Joseph 2000). The reticular system is in a position to quickly induce arousal so that attention may be selectively directed at sensory stimuli of potential importance. The system exerts its widespread influences on sensory and motor functions and arousal through neurotransmitters such as norepinephrine and serotonin. While the system may be activated and inhibited by the amygdala, hypothalamus, and orbitofrontal cortex, it may also be activated independently of these structures in a more reflex-like manner (Lipscomb & Hodges 1996; Tranel 2000). Brain stem reflexes to music rely on the early stages of auditory processing. When an auditory signal reaches the primary auditory cortex, the signal has already undergone a number of analyses by such brain structures as the superior olivary complex, the inferior colliculus, and the thalamus (Koelsch & Siebel 2005). Accordingly, alarm signals to auditory events that suggest “danger” may be emitted as early as at the level of the inferior colliculus. Brain stem reflexes are “hard-wired.” ［按：這裡指出腦幹反射是快速而粗糙的處理，近乎本能］Thus, for instance, the perceived pleasantness and unpleasantness of sensory consonance and dissonance reflect how the hearing system divides frequencies into critical bandwidths: If the frequency separation of two tones is either very small or larger than the critical bandwidth, the tones will be judged as consonant. If the separation is about one-fourth of a critical band, the tones will be judged as maximally dissonant (Lipscomb & Hodges 1996). Sensory dissonance is suggestive of “danger” in natural environments, because it occurs in the “threat” and “warning” calls of many species of animals (Ploog 1992). Dissonance may thus have been selected by evolution as an unlearned negative reinforcer of behavior (Rolls 2007).
Brain stem reflexes are quick and automatic, as shown by evidence of rapid and pre-attentive categorization of subtle timbral differences associated with different emotions (Goydkeetal.2004), and affective priming effects of consonant and dissonant chords (Sollberger et al. 2003). Brain stem reflexes to music may function even prior to birth, as indicated by findings that playing loud music to fetuses produces heart rate accelerations and increased motor responses, whereas soft music produces moderate heart rate decelerations and reduced movement (for a review, see Lecanuet 1996). The arousal-inducing properties of music were investigated and theorized by Berlyne (1971).7 According to Berlyne’s theory, listeners will prefer musical stimuli that induce an “optimum” level of physiological arousal. If the “arousal potential” of the music is too high, listeners will reject the music. Similarly, if the arousal potential is too low, listeners will reject the music. Hence, Berlyne hypothesized that listeners’ preferences are related to arousal (or some aspect of it, such as speed or loudness) in the form of an inverted U-shaped curve (the Wundt curve). ［按：這裡指出腦幹反射導致的激發，跟聽眾的喜好程度呈倒U曲線］Berlyne’s theory has received some empirical support from experimental studies (for a review, see North & Hargreaves 1997). In addition, several studies have shown that listeners use music to regulate their arousal in order to obtain optimal arousal (DeNora 2001; Thayer 1996). However, what is judged as “optimal” by a listener varies depending on the situation (North & Hargreaves 1997) and on personality characteristics of the listener (McNamara & Ballard 1999). Thus, it may be difficult to predict arousal responses without taking individual and contextual factors into consideration. Brain stem reflexes can explain the stimulating and relaxing effects of music, and how mere sounds may induce pleasantness and unpleasantness. However, it is unclear how the mechanism could explain the induction of specific emotions.