Table_1_Investigating the Role of the Primary Motor Cortex in Musical Creativity: A Transcranial Direct Current Stimulation Study.DOCX

Neuroscientific research has revealed interconnected brain networks implicated in musical creativity, such as the executive control network, the default mode network, and premotor cortices. The present study employed brain stimulation to evaluate the role of the primary motor cortex (M1) in creative and technically fluent jazz piano improvisations. We implemented transcranial direct current stimulation (tDCS) to alter the neural activation patterns of the left hemispheric M1 whilst pianists performed improvisations with their right hand. Two groups of expert jazz pianists (n = 8 per group) performed five improvisations in each of two blocks. In Block 1, they improvised in the absence of brain stimulation. In Block 2, one group received inhibitory tDCS and the second group received excitatory tDCS while performing five new improvisations. Three independent expert-musicians judged the 160 performances on creativity and technical fluency using a 10-point Likert scale. As the M1 is involved in the acquisition and consolidation of motor skills and the control of hand orientation and velocity, we predicted that excitatory tDCS would increase the quality of improvisations relative to inhibitory tDCS. Indeed, improvisations under conditions of excitatory tDCS were rated as significantly more creative than those under conditions of inhibitory tDCS. A music analysis indicated that excitatory tDCS elicited improvisations with greater pitch range and number/variety of notes. Ratings of technical fluency did not differ significantly between tDCS groups. We discuss plausible mechanisms by which the M1 region contributes to musical creativity.

神经科学研究已揭示出与音乐创造力相关的互联脑网络，例如执行控制网络（executive control network）、默认模式网络（default mode network）以及运动前皮层（premotor cortices）。本研究采用脑刺激手段，评估初级运动皮层（primary motor cortex, M1）在兼具创造力与技术流畅性的爵士钢琴即兴演奏中的作用。我们通过经颅直流电刺激（transcranial direct current stimulation, tDCS）调节左侧半球M1的神经激活模式，同时让钢琴演奏者用右手进行即兴演奏。两组专业爵士钢琴演奏者（每组样本量n=8）在两个实验区块中各完成五段即兴演奏。在区块1中，演奏者在无脑刺激的条件下进行即兴创作；区块2中，一组接受抑制性tDCS，另一组接受兴奋性tDCS，同时完成五段全新的即兴演奏。三名独立的专业音乐家以10分李克特量表（Likert scale），对全部160段演奏的创造力与技术流畅度进行评分。鉴于M1参与运动技能的习得与巩固，以及手部方位与速度的调控，我们预测相较于抑制性tDCS，兴奋性tDCS可提升即兴演奏的质量。实验结果确证，兴奋性tDCS条件下的即兴演奏被评为显著更具创造力。音乐分析显示，兴奋性tDCS诱导产生的即兴演奏具有更广的音域以及更多样的音符数量与种类。两组的技术流畅度评分无显著差异。最后我们讨论了M1区域助力音乐创造力的潜在合理机制。