The Key Lab of Brain Functional Genomics, MOE & STCSM, School of Psychology and Cognitive Science, East China Normal University, Shanghai, China.
NYU-ECNU Institute of Brain and Cognitive Science, NYU Shanghai and Collaborative Innovation Center for Brain Science, Shanghai, China.
Cereb Cortex. 2018 Oct 1;28(10):3468-3477. doi: 10.1093/cercor/bhx213.
In the present study, we searched for causal evidence linking activity in the bilateral primary somatosensory cortex (SI), posterior parietal cortex (PPC), and prefrontal cortex (PFC) with behavioral performance in vibrotactile working memory. Participants performed a vibrotactile delayed matching-to-sample task, while single-pulse transcranial magnetic stimulation (sp-TMS) was applied over these cortical areas at 100, 200, 300, 600, 1600, and 1900 ms after the onset of vibrotactile stimulation (200 ms duration). In our experiments, sp-TMS over the contralateral SI at the early delay (100 and 200 ms) deteriorated the accuracy of task performance, and over the ipsilateral SI at the late delay (1600 and 1900 ms) also induced such deteriorating effects. Furthermore, deteriorating effects caused by sp-TMS over the contralateral DLPFC at the same maintenance stage (1600 ms) were correlated with the effects caused by sp-TMS over the ipsilateral SI, indicating that information retained in the ipsilateral SI during the late delay may be associated with the DLPFC. Taken together, these results suggest that both the contralateral and ipsilateral SIs are involved in tactile WM, and the contralateral DLPFC bridges the contralateral SI and ipsilateral SI for goal-directed action.
在本研究中，我们搜索了与行为表现相关的因果证据，这些证据将双侧初级体感皮层（SI）、后顶叶皮层（PPC）和前额叶皮层（PFC）的活动与触觉工作记忆中的行为表现联系起来。参与者执行了触觉延迟匹配样本任务，同时在触觉刺激开始后 100、200、300、600、1600 和 1900 毫秒（200 毫秒持续时间）时，对这些皮层区域施加单次脉冲经颅磁刺激（sp-TMS）。在我们的实验中，在早期延迟（100 和 200 毫秒）时对右侧 SI 的 sp-TMS 会降低任务表现的准确性，而在晚期延迟（1600 和 1900 毫秒）时对左侧 SI 的 sp-TMS 也会引起这种恶化效应。此外，在相同的维持阶段（1600 毫秒）对右侧背外侧前额叶皮层（DLPFC）施加 sp-TMS 引起的恶化效应与对左侧 SI 施加 sp-TMS 引起的效应相关，表明在晚期延迟期间保留在左侧 SI 中的信息可能与 DLPFC 相关。综上所述，这些结果表明，双侧 SI 都参与了触觉 WM，而对侧 DLPFC 则为目标导向行为连接了对侧 SI 和同侧 SI。
