Comparison of block and event-related fMRI designs in evaluating the word-frequency effect
Comparison of block and event-related fMRI designs in evaluating the word-frequency effect
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DOI：
10.1002/hbm.10092
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发表时间：
2003-03-01
影响因子：
4.8
通讯作者：
Siong, SC
中科院分区：
文献类型：
--
作者：
Chee, MWL;Venkatraman, V;Siong, SC
在需要联想语义判断的任务中，打印词频可以调节检索努力。事件相关的fMRI虽然避免了刺激顺序的可预测性，但在理论上统计上比块设计更弱。我们比较了一个事件相关设计和两个评估相同语义判断任务的块设计，发现相似的大脑区域表现出词频效应。虽然反应幅度较低，但与块设计相比，事件相关的fMRI能够检测到词频效应。频率效应的检测与事件相关的设计也一样。这表明刺激顺序的可预测性在块设计中可能不像想象的那样是一个严重的问题。嗡嗡声。脑科学学报，2003。(C) 2003 Wiley-Liss, Inc。
Printed word frequency can modulate retrieval effort in a task requiring associative semantic judgment. Event-related fMRI, while avoiding stimulus order predictability, is in theory statistically less powerful than block designs. We compared one event-related and two block designs that evaluated the same semantic judgment task and found that similar brain regions demonstrated the word frequency effect. Although the responses were lower in amplitude, event-related fMRI was able to detect the word frequency effect to a comparable degree compared to the block designs. The detection of a frequency effect with the event-related design also.suggests that stimulus-order predictability may not be as serious a concern in block designs as might be supposed. Hum. Brain Mapping 18:186-193, 2003. (C) 2003 Wiley-Liss, Inc.