Knobloch Simon, Haul Philipp, Rusche Saskia, Paland Heiko, Zokai Darius, Haaf Moritz, Rauh Jonas, Mulert Christoph, Leicht Gregor
Department of Psychiatry and Psychotherapy, Psychiatric Neuroimaging Branch, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Ludwig-Maximilians-University of Munich, Munich, Germany.
PLoS One. 2025 Sep 26;20(9):e0333510. doi: 10.1371/journal.pone.0333510. eCollection 2025.
When confronted with dichotically presented syllables, right-handed healthy individuals tend to consciously perceive syllables presented to the right ear more often. This phenomenon, known as the right-ear advantage, is driven by delayed processing of information from the left ear in left temporal auditory cortex due to its indirect relay through the corpus callosum. In contrast, less is known about about the corresponding mechanisms for stimuli processed in the right temporal hemisphere. In this study, we developed a melody-based dichotic listening paradigm designed to induce a left-ear advantage. This novel paradigm, alongside a classical syllable-based paradigm was tested in 40 healthy right-handed participants. We also examined the influence of musical education on lateralization of auditory processing. Our results revealed a significant left-ear advantage for the perception of dichotically presented melodies and replicated established findings of a right-ear advantage for syllables. No group differences emerged between participants with or without current or past musical practice. However, among those with musical training, a greater number of years of practice was associated with a reduced right-ear advantage for syllables and an increased report of melodies presented to the left-ear. These findings suggest that the left-ear advantage in dichotic perception of melodies reflects right hemispheric processing of musical stimuli. Moreover, monitoring of the left ear seems to be altered by musical practice. Future research using neuroimaging techniques will be necessary to confirm this finding.
当面对双耳分听呈现的音节时，右利手的健康个体往往更频繁地有意识地感知呈现给右耳的音节。这种现象被称为右耳优势，是由于来自左耳的信息通过胼胝体间接传递，导致左颞叶听觉皮层对其处理延迟所致。相比之下，对于右颞叶半球处理的刺激的相应机制了解较少。在本研究中，我们开发了一种基于旋律的双耳分听范式，旨在诱导左耳优势。这种新颖的范式与经典的基于音节的范式一起在40名右利手健康参与者中进行了测试。我们还研究了音乐教育对听觉处理偏侧化的影响。我们的结果显示，在双耳分听呈现的旋律感知方面存在显著的左耳优势，并重复了已有的关于音节右耳优势的研究结果。有或没有当前或过去音乐练习经历的参与者之间没有出现组间差异。然而，在有音乐训练的参与者中，练习年限越长，音节的右耳优势降低，左耳呈现的旋律报告增加。这些发现表明，双耳分听旋律时的左耳优势反映了右半球对音乐刺激的处理。此外，音乐练习似乎改变了对左耳的监测。未来有必要使用神经成像技术进行研究以证实这一发现。
