Marangolo Paola, Fiori Valentina, Caltagirone Carlo, Incoccia Chiara, Gili Tommaso
Università Federico II, 80133, Naples, Italy; IRCCS, Fondazione Santa Lucia, 00179, Rome, Italy.
IRCCS, Fondazione Santa Lucia, 00179, Rome, Italy.
Brain Res. 2020 Jan 15;1727:146564. doi: 10.1016/j.brainres.2019.146564. Epub 2019 Nov 22.
It has long been assumed that the language function is hierarchically organized into specific cortical areas. Here, for the first time, we present direct evidence that the spinal cord takes part in language processing. In a randomized-double blind design, sixteen aphasics underwent a language treatment combined with transcutaneous spinal direct current stimulation (tsDCS). During the treatment, each subject received tsDCS (20 min, 2 mA) over the thoracic vertebrae (IX-X vertebrae) in two different conditions: (1) anodal, and (2) sham while performing a verb naming task. Each experimental condition was run in five consecutive daily sessions over two weeks. Before and after each condition, all patients underwent a resting state functional magnetic resonance imaging (rs-fMRI). After anodal tsDCS, significant functional connectivity changes were found in a cerebellar-cortical network recruiting regions such as the left cerebellum, the right parietal and premotor cortex known to be also involved in action-related verb processing. Indeed, this increase of connectivity significantly correlated with the greatest amount of improvement found in verb naming. In line with our experimental data, we also found a greater improvement after anodal tsDCS also on untreated items of the language test but only on tasks which required the use of verbs, such as verb naming and picture description. No significant changes were found in noun naming. Thus, this evidence emphasizes, for the first time, that the neural response due to tsDCS combined with language treatment changes during the course of recovery by enhancing activity into cortical regions which influence verb processing.
长期以来，人们一直认为语言功能是分层组织在特定的皮质区域中的。在此，我们首次提供了直接证据，证明脊髓参与语言处理。在一项随机双盲设计中，16名失语症患者接受了语言治疗，并结合经皮脊髓直流电刺激（tsDCS）。在治疗过程中，每个受试者在两种不同条件下接受tsDCS（20分钟，2毫安）刺激胸椎（第九至十胸椎）：（1）阳极刺激，（2）假刺激，同时执行动词命名任务。每种实验条件在两周内连续进行五个每日疗程。在每种条件前后，所有患者都接受了静息态功能磁共振成像（rs-fMRI）。阳极tsDCS后，在一个小脑-皮质网络中发现了显著的功能连接变化，该网络招募了诸如左小脑、右顶叶和运动前皮质等区域，这些区域也已知参与与动作相关的动词处理。事实上，这种连接性的增加与动词命名中发现的最大改善量显著相关。与我们的实验数据一致，我们还发现，在语言测试的未治疗项目上，阳极tsDCS后也有更大的改善，但仅在需要使用动词的任务上，如动词命名和图片描述。在名词命名中未发现显著变化。因此，这一证据首次强调，由于tsDCS与语言治疗相结合而产生的神经反应在恢复过程中通过增强影响动词处理的皮质区域的活动而发生变化。
