Preibisch Christine, Raab Peter, Neumann Katrin, Euler Harald A, von Gudenberg Alexander W, Gall Volker, Lanfermann Heinrich, Zanella Friedhelm
Department of Neuroradiology, University Frankfurt, Frankfurt, Germany.
Neuroimage. 2003 Jul;19(3):1076-84. doi: 10.1016/s1053-8119(03)00157-5.
The purpose of this study was to establish functional magnetic resonance imaging (fMRI) for the investigation of brain function during overt speech production in stuttering. Up to now this technique has rarely been used for the investigation of speech production paradigms because artifacts related to overt speaking largely impair the sensitivity toward task-related activation. Recently, the temporal delay of the hemodynamic response has been exploited to achieve a suppression of speech-related artifacts. By the limitation to very short utterances (one word), a temporal segregation of the respective effects was accomplished by means of an event-related experimental design. However, the investigation of speech production in persons who stutter requires a more extensive speaking situation. Since longer and more complex utterances evoke more symptoms of stuttering than reading of single words, a useful task should at least include the reading of full sentences. In this study we performed simulations to investigate the correlation of speech-related artifacts with the respective hemodynamic response in dependency on speech duration and rate of data sampling. Furthermore, we show that prolonged stimulus durations and repetition times of 3 s still allow an effective suppression of speech-related artifacts in fluent as well as in nonfluent speakers. Not only were obvious false activations at high contrast cerebrospinal fluid tissue borders widely eliminated, subjects also displayed consistent activation in speech-related and motor areas. As these results widely resemble those obtained by earlier neuroimaging studies on language production, event-related fMRI seems to be capable of recording neurophysiological correlates of overt speech production.
本研究的目的是建立功能磁共振成像（fMRI）技术，用于研究口吃者在公开言语产生过程中的脑功能。到目前为止，这项技术很少用于言语产生范式的研究，因为与公开讲话相关的伪影在很大程度上损害了对任务相关激活的敏感性。最近，血流动力学反应的时间延迟被用来抑制与言语相关的伪影。通过限制为非常短的话语（一个单词），借助事件相关实验设计实现了各自效应的时间分离。然而，对口吃者言语产生的研究需要更广泛的言语情境。由于更长、更复杂的话语比单字阅读引发更多的口吃症状，一个有用的任务至少应包括完整句子的阅读。在本研究中，我们进行了模拟，以研究与言语相关的伪影与各自血流动力学反应之间的相关性，该相关性取决于言语持续时间和数据采样率。此外，我们表明，延长刺激持续时间和重复时间至3秒，仍能有效抑制流利和不流利说话者与言语相关的伪影。不仅高对比度脑脊液组织边界处明显的假激活被广泛消除，受试者在与言语相关和运动区域也表现出一致的激活。由于这些结果与早期关于语言产生的神经影像学研究结果非常相似，事件相关fMRI似乎能够记录公开言语产生的神经生理相关因素。
