Department of Clinical Psychology, Kharazmi University, Tehran, Iran.
Institute for Cognitive and Brain Science, Shahid Beheshti University, Evin Sq., 19839-63113, Tehran, Iran.
Exp Brain Res. 2019 Oct;237(10):2607-2619. doi: 10.1007/s00221-019-05616-w. Epub 2019 Aug 1.
The arrangement of musical notes and their time intervals, also known as musical rhythm is one of the core elements of music. Nevertheless, the cognitive process and neural mechanism of the human brain that underlay the perception of musical rhythm are poorly understood. In this study, we hypothesized that changes in musical rhythmic patterns alter the emotional content expressed by music and the way it is perceived, that assumably causes specific changes in the brain functional connectome. Therefore, 18 male children aged 10-14 years old were recruited and exposed to 12 musical excerpts while their brain's electrical activity was recorded using a 32-channel EEG recorder. The musical rhythmic patterns were changed by manipulating only note values in beats while keeping time signature and other elements in a fixed state. The experienced emotions were assessed using a 2-dimensional self-assessment manikin questionnaire. The behavioral data showed that an increase in the complexity of musical rhythmic patterns significantly enhances perceived valence and arousal levels. In addition, the pattern of brain functional connectivity was also estimated using the weighted phase lag index and their association with behavioral changes was calculated. Interestingly, the behavioral changes were mainly associated with alteration of brain functional connectivity at the alpha band in the fronto-central connections. These results emphasize the important role of the motor cortical site-fronto-central connections, in the perception of musical rhythmic pattern. These findings may improve conception of the underlying brain mechanism involved in the perception of musical rhythm.
音符及其时间间隔的排列，也称为音乐节奏，是音乐的核心要素之一。然而，人类大脑感知音乐节奏的认知过程和神经机制仍知之甚少。在这项研究中，我们假设音乐节奏模式的变化改变了音乐所表达的情感内容和感知方式，这可能导致大脑功能连接组发生特定的变化。因此，我们招募了 18 名 10-14 岁的男性儿童，并让他们在暴露于 12 首音乐片段的同时使用 32 通道 EEG 记录器记录他们大脑的电活动。通过仅改变节拍中的音符值而保持时间标记和其他元素处于固定状态来改变音乐节奏模式。使用二维自我评估情绪量表评估所经历的情绪。行为数据表明，音乐节奏模式复杂性的增加显著提高了感知的愉悦度和唤醒度。此外，还使用加权相位滞后指数估计了大脑功能连接模式，并计算了它们与行为变化的关联。有趣的是，行为变化主要与额中央连接中的α频段的大脑功能连接改变有关。这些结果强调了运动皮质位点-额中央连接在感知音乐节奏模式中的重要作用。这些发现可能有助于理解涉及音乐节奏感知的大脑机制。
