Santosa Hendrik, Hong Melissa Jiyoun, Hong Keum-Shik
Department of Cogno-Mechatronics Engineering, Pusan National University Busan, South Korea.
Department of Education Policy and Social Analysis, Columbia University New York, NY, USA.
Front Behav Neurosci. 2014 Dec 9;8:418. doi: 10.3389/fnbeh.2014.00418. eCollection 2014.
The present study is to determine the effects of background noise on the hemispheric lateralization in music processing by exposing 14 subjects to four different auditory environments: music segments only, noise segments only, music + noise segments, and the entire music interfered by noise segments. The hemodynamic responses in both hemispheres caused by the perception of music in 10 different conditions were measured using functional near-infrared spectroscopy. As a feature to distinguish stimulus-evoked hemodynamics, the difference between the mean and the minimum value of the hemodynamic response for a given stimulus was used. The right-hemispheric lateralization in music processing was about 75% (instead of continuous music, only music segments were heard). If the stimuli were only noises, the lateralization was about 65%. But, if the music was mixed with noises, the right-hemispheric lateralization has increased. Particularly, if the noise was a little bit lower than the music (i.e., music level 10~15%, noise level 10%), the entire subjects showed the right-hemispheric lateralization: This is due to the subjects' effort to hear the music in the presence of noises. However, too much noise has reduced the subjects' discerning efforts.
本研究旨在通过让14名受试者处于四种不同的听觉环境中，来确定背景噪声对音乐处理中半球侧化的影响：仅音乐片段、仅噪声片段、音乐 + 噪声片段，以及整个音乐被噪声片段干扰。使用功能近红外光谱法测量了在10种不同条件下由音乐感知引起的两个半球的血液动力学反应。作为区分刺激诱发血液动力学的一个特征，使用了给定刺激的血液动力学反应的平均值与最小值之间的差异。音乐处理中的右半球侧化约为75%（不是连续的音乐，只听到音乐片段）。如果刺激只是噪声，侧化约为65%。但是，如果音乐与噪声混合，右半球侧化会增加。特别是，如果噪声比音乐略低（即音乐水平10%~15%，噪声水平10%）时，所有受试者都表现出右半球侧化：这是由于受试者在有噪声的情况下努力去听音乐所致。然而，如果噪声过多，会降低受试者的辨别能力。
