Friston K J, Fletcher P, Josephs O, Holmes A, Rugg M D, Turner R
The Wellcome Department of Cognitive Neurology, Institute of Neurology, London, United Kingdom.
Neuroimage. 1998 Jan;7(1):30-40. doi: 10.1006/nimg.1997.0306.
We present an approach to characterizing the differences among event-related hemodynamic responses in functional magnetic resonance imaging that are evoked by different sorts of stimuli. This approach is predicated on a linear convolution model and standard inferential statistics as employed by statistical parametric mapping. In particular we model evoked responses, and their differences, in terms of basis functions of the peri-stimulus time. This facilitates a characterization of the temporal response profiles that has a high effective temporal resolution relative to the repetition time. To demonstrate the technique we examined differential responses to visually presented words that had been seen prior to scanning or that were novel. The form of these differences involved both the magnitude and the latency of the response components. In this paper we focus on bilateral ventrolateral prefrontal responses that show deactivations for previously seen words and activations for novel words.
我们提出了一种方法，用于表征功能磁共振成像中由不同类型刺激诱发的事件相关血流动力学反应之间的差异。该方法基于线性卷积模型和统计参数映射所采用的标准推断统计。特别是，我们根据刺激周围时间的基函数对诱发反应及其差异进行建模。这有助于表征时间反应轮廓，相对于重复时间而言，该轮廓具有较高的有效时间分辨率。为了演示该技术，我们研究了对扫描前看过或新颖的视觉呈现单词的差异反应。这些差异的形式涉及反应成分的幅度和潜伏期。在本文中，我们重点关注双侧腹外侧前额叶反应，该反应对先前看过的单词表现出失活，对新颖单词表现出激活。
