Ren Lanlan, Lv Mengjie, Wang Xiyuan, Schwieter John W, Liu Huanhuan
Research Center of Brain and Cognitive Neuroscience, Liaoning Normal University, 850 Huanghe Road, Shahekou District, Liaoning Province, Dalian 116029, China.
Key Laboratory of Brain and Cognitive Neuroscience, Liaoning Normal University, 850 Huanghe Road, Shahekou District, Liaoning Province, Dalian 116029, China.
Cereb Cortex. 2024 Sep 3;34(9). doi: 10.1093/cercor/bhae356.
Repeated exposure to word forms and meanings improves lexical knowledge acquisition. However, the roles of domain-general and language-specific brain regions during this process remain unclear. To investigate this, we applied intermittent theta burst stimulation over the domain-general (group left dorsolateral prefrontal cortex) and domain-specific (Group L IFG) brain regions, with a control group receiving sham intermittent theta burst stimulation. Intermittent theta burst stimulation effects were subsequently assessed in functional magnetic resonance imaging using an artificial word learning task which consisted of 3 learning phases. A generalized psychophysiological interaction analysis explored the whole brain functional connectivity, while dynamic causal modeling estimated causal interactions in specific brain regions modulated by intermittent theta burst stimulation during repeated exposure. Compared to sham stimulation, active intermittent theta burst stimulation improved word learning performance and reduced activation of the left insula in learning phase 2. Active intermittent theta burst stimulation over the domain-general region increased whole-brain functional connectivity and modulated effective connectivity between brain regions during repeated exposure. This effect was not observed when active intermittent theta burst stimulation was applied to the language-specific region. These findings suggest that the domain-general region plays a crucial role in word formation rule learning, with intermittent theta burst stimulation enhancing whole-brain connectivity and facilitating efficient information exchange between key brain regions during new word learning.
反复接触单词形式和含义可提高词汇知识的习得。然而，在此过程中，通用领域和特定语言的脑区所起的作用仍不清楚。为了对此进行研究，我们对通用领域（左侧背外侧前额叶皮层组）和特定领域（左侧额下回组）脑区施加间歇性theta爆发刺激，对照组接受假间歇性theta爆发刺激。随后，在功能磁共振成像中使用由三个学习阶段组成的人工单词学习任务来评估间歇性theta爆发刺激的效果。广义心理生理交互分析探索全脑功能连接，而动态因果模型估计在重复接触期间由间歇性theta爆发刺激调制的特定脑区中的因果交互。与假刺激相比，主动间歇性theta爆发刺激提高了单词学习性能，并在学习阶段2降低了左侧脑岛的激活。在通用领域区域进行的主动间歇性theta爆发刺激增加了全脑功能连接，并在重复接触期间调节了脑区之间的有效连接。当对特定语言区域施加主动间歇性theta爆发刺激时，未观察到这种效果。这些发现表明，通用领域区域在单词形成规则学习中起关键作用，间歇性theta爆发刺激可增强全脑连接，并在新单词学习期间促进关键脑区之间的高效信息交换。
