The functional anatomu of inspection time: an eventt-related fMRI study
The functional anatomu of inspection time: an eventt-related fMRI study
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DOI：
10.1016/j.neuroimage.2004.03.047
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发表时间：
2004-08-01
期刊：
影响因子：
5.7
通讯作者：
Wardlaw, JM
中科院分区：
文献类型：
--
作者：
Deary, IJ;Simonotto, E;Wardlaw, JM
20名健康的年轻成年人在执行视觉检查时间任务时接受了大脑的功能磁共振成像(FMRI)。检查时间是一项强迫选择、两种选择的视觉后向掩蔽任务，在这项任务中，受试者被短暂地展示了两条长度明显不同的平行垂直线，并且必须决定哪一条更长。随着刺激持续时间的缩短，表现会下降到偶然性水平。检查时间的个体差异与较高的认知功能相关。研究采用与事件相关的设计。血流动力学(取决于血氧水平；BOLD)的反应被计算为从6INS(表现几乎是偶然的)到150ms(表现近乎完美)的8个刺激持续水平的函数，以及行为反应的函数。随机效应分析显示，视觉辨别困难与双侧额盖下回、额上回、额内侧回和前扣带回激活，双侧后扣带回和楔前回失活有关。对大胆反应的时间进程的研究表明，激活与更困难、更短暂的刺激特别相关，而去激活在大多数刺激水平上都被发现。功能连通性表明存在两个网络。其中一个包括额顶区、鞍内区、额叶内侧回和前扣带回(ACC)，可能与视觉退化知觉的加工有关。感觉相关和联想区域的后方网络可能有助于视觉辨别任务的加工，该任务具有较高的加工要求，并结合了几个基本的认知域。因此，功能磁共振成像可以揭示在非常短的持续时间内发生的心理事件的神经关联信息。(C)2004 Elsevier Inc.保留所有权利。
Twenty healthy young adults underwent functional magnetic resonance imaging (fMRI) of the brain while performing a visual inspection time task. Inspection time is a forced-choice, two-alternative visual backward-masking task in which the subject is briefly shown two parallel vertical lines of markedly different lengths and must decide which is longer. As stimulus duration decreases, performance declines to chance levels. Individual differences in inspection time correlate with higher cognitive functions. An event-related design was used. The hemodynamic (blood oxygenation level-dependent; BOLD) response was computed as both a function of the eight levels of stimulus duration, from 6 ins (where performance is almost at chance) to 150 ms (where performance is nearly perfect), and a function of the behavioral responses. Random effects analysis showed that the difficulty of the visual discrimination was related to bilateral activation in the inferior fronto-opercular cortex, superior/medial frontal gyros, and anterior cingulate gyrus, and bilateral deactivation in the posterior cingulate gyrus and precuneus. Examination of the time courses of BOLD responses showed that activation was related specifically to the more difficult briefer stimuli and that deactivation was found across most stimulus levels. Functional connectivity suggested the existence of two networks. One comprised the fronto-opercular area, intrasylvian area, medial frontal gyrus, and the anterior cingulate cortex (ACC), possibly associated with processing of visually degraded percepts. A posterior network of sensory-related and associative regions might subserve processing of a visual discrimination task that has high processing demands and combines several fundamental cognitive domains. fMRI can thus reveal information about the neural correlates of mental events which occur over very short durations. (C) 2004 Elsevier Inc. All rights reserved.