Otten L J, Rugg M D
Institute of Cognitive Neuroscience, University College London, 17 Queen Square, London WC1N 3AR, UK.
Cereb Cortex. 2001 Dec;11(12):1150-60. doi: 10.1093/cercor/11.12.1150.
Using event-related functional magnetic resonance imaging (fMRI), the neural correlates of memory encoding can be studied by contrasting item-related activity elicited in a study task according to whether the items are remembered or forgotten in a subsequent memory test. Previous studies using this approach have implicated the left prefrontal cortex in the successful encoding of verbal material into episodic memory when the study task is semantic in nature. In the current study, we asked whether the neural correlates of episodic encoding differ depending on type of study task. Seventeen volunteers participated in an event-related fMRI experiment in which at study, volunteers were cued to make either animacy or syllable judgements about words. A recognition memory test followed after a delay of approximately 15 min. For the animacy task, words that were subsequently remembered showed greater activation in left and medial prefrontal regions. For the syllable task, by contrast, successful memory for words was associated with activations in bilateral intraparietal sulcus, bilateral fusiform gyrus, right prefrontal cortex and left superior occipital gyrus. These findings suggest that the brain networks supporting episodic encoding differ according to study task.
使用事件相关功能磁共振成像（fMRI），通过对比在研究任务中根据项目在后续记忆测试中是被记住还是被遗忘而引发的与项目相关的活动，就可以研究记忆编码的神经关联。以前使用这种方法的研究表明，当研究任务本质上是语义性的时候，左前额叶皮层参与了将言语材料成功编码到情景记忆中。在当前的研究中，我们探讨了情景编码的神经关联是否会因研究任务类型的不同而有所差异。17名志愿者参与了一项事件相关fMRI实验，在研究过程中，志愿者被提示对单词做出关于生动性或音节的判断。大约15分钟的延迟后进行识别记忆测试。对于生动性任务，随后被记住的单词在左前额叶和内侧前额叶区域表现出更强的激活。相比之下，对于音节任务，单词的成功记忆与双侧顶内沟、双侧梭状回、右前额叶皮层和左枕上回的激活有关。这些发现表明，支持情景编码的脑网络会因研究任务的不同而有所差异。
