Department of Neuroscience, Retzius väg 8, Karolinska Institutet, 17177 Stockholm, Sweden.
Cereb Cortex. 2018 Jan 1;28(1):387-394. doi: 10.1093/cercor/bhx299.
Numerous cross-sectional and observational longitudinal studies show associations between expertise and regional brain anatomy. However, since these designs confound training with genetic predisposition, the causal role of training remains unclear. Here, we use a discordant monozygotic (identical) twin design to study expertise-dependent effects on neuroanatomy using musical training as model behavior, while essentially controlling for genetic factors and shared environment of upbringing. From a larger cohort of monozygotic twins, we were able to recruit 18 individuals (9 pairs) that were highly discordant for piano practice. We used structural and diffusion magnetic resonance imaging to analyze the auditory-motor network and within-pair differences in cortical thickness, cerebellar regional volumes and white-matter microstructure/fractional anisotropy. The analyses revealed that the musically active twins had greater cortical thickness in the auditory-motor network of the left hemisphere and more developed white matter microstructure in relevant tracts in both hemispheres and the corpus callosum. Furthermore, the volume of gray matter in the left cerebellar region of interest comprising lobules I-IV + V, was greater in the playing group. These findings provide the first clear support for that a significant portion of the differences in brain anatomy between experts and nonexperts depend on causal effects of training.
许多横断面和观察性纵向研究表明，专业知识与大脑区域解剖结构之间存在关联。然而，由于这些设计将训练与遗传易感性混淆在一起，因此训练的因果作用仍不清楚。在这里，我们使用不一致的同卵（相同）双胞胎设计，使用音乐训练作为模型行为，来研究神经解剖结构与专业知识之间的相关性，同时基本控制遗传因素和成长环境的影响。在一个更大的同卵双胞胎队列中，我们招募了 18 名（9 对）高度不一致的钢琴练习者。我们使用结构和扩散磁共振成像来分析听觉-运动网络以及皮质厚度、小脑区域体积和白质微观结构/各向异性的个体内差异。分析结果表明，在左半球的听觉-运动网络中，音乐活跃的双胞胎大脑皮质厚度更大，两个半球和胼胝体的相关区域的白质微观结构更发达。此外，在包含 I-IV + V 叶的左小脑感兴趣区的灰质体积在演奏组中更大。这些发现首次明确支持这样一种观点，即专家和非专家之间大脑解剖结构的差异很大程度上取决于训练的因果作用。
