Data_Sheet_1_Chronology of auditory processing and related co-activation in the orbitofrontal cortex depends on musical expertise.docx

IntroductionThe present study aims to explore the extent to which auditory processing is reflected in the prefrontal cortex.
MethodsUsing magnetoencephalography (MEG), we investigated the chronology of primary and secondary auditory responses and associated co-activation in the orbitofrontal cortex in a large cohort of 162 participants of various ages. The sample consisted of 38 primary school children, 39 adolescents, 43 younger, and 42 middle-aged adults and was further divided into musically experienced participants and non-musicians by quantifying musical training and aptitude parameters.
ResultsWe observed that the co-activation in the orbitofrontal cortex [Brodmann-Area 10 (BA10)] strongly depended on musical expertise but not on age. In the musically experienced groups, a systematic coincidence of peak latencies of the primary auditory P1 response and the co-activated response in the orbitofrontal cortex was observed in childhood at the onset of musical education. In marked contrast, in all non-musicians, the orbitofrontal co-activation occurred 25–40 ms later when compared with the P1 response. Musical practice and musical aptitude contributed equally to the observed activation and co-activation patterns in the auditory and orbitofrontal cortex, confirming the reciprocal, interrelated influence of nature, and nurture in the musical brain.
DiscussionBased on the observed ageindependent differences in the chronology and lateralization of neurological responses, we suggest that orbitofrontal functions may contribute to musical learning at an early age.

引言
本研究旨在探讨听觉加工在前额叶皮层（prefrontal cortex）中的体现程度。

方法
本研究采用脑磁图（magnetoencephalography, MEG）技术，针对162名覆盖不同年龄段的大样本参与者，探究了眶额皮层（orbitofrontal cortex）内初级与次级听觉反应的时序特征及相关共激活模式。该样本包含38名小学生、39名青少年、43名青年成人及42名中年成人，并通过量化音乐训练与音乐能力参数，将参与者划分为有音乐训练经验组与非音乐家组。

结果
本研究观察到，眶额皮层内的共激活模式[布罗德曼10区（Brodmann-Area 10, BA10）]强烈依赖于音乐专业水平，而非年龄因素。在有音乐训练经验的组别中，儿童在开启音乐教育之初，便出现了初级听觉P1反应峰潜伏期与眶额皮层共激活反应峰潜伏期的系统性重合。与之形成鲜明对比的是，所有非音乐家的眶额皮层共激活均较P1反应延迟25~40毫秒。音乐练习与音乐能力对听觉皮层及眶额皮层的激活与共激活模式的贡献程度相当，这证实了音乐大脑中先天禀赋与后天培养的双向相互影响。

讨论
基于所观察到的神经反应时序与偏侧化特征不受年龄影响的差异，我们提出眶额皮层功能可能在儿童早期的音乐学习中发挥作用。