de Zubicaray Greig, McMahon Katie, Eastburn Mathew, Pringle Alan J, Lorenz Lina, Humphreys Michael S
Centre for Magnetic Resonance, The University of Queensland, QLD, Australia.
Neuropsychologia. 2007 Mar 2;45(4):824-35. doi: 10.1016/j.neuropsychologia.2006.08.013. Epub 2006 Sep 20.
Cued recall and item recognition are considered the standard episodic memory retrieval tasks. However, only the neural correlates of the latter have been studied in detail with fMRI. Using an event-related fMRI experimental design that permits spoken responses, we tested hypotheses from an auto-associative model of cued recall and item recognition [Chappell, M., & Humphreys, M. S. (1994). An auto-associative neural network for sparse representations: Analysis and application to models of recognition and cued recall. Psychological Review, 101, 103-128]. In brief, the model assumes that cues elicit a network of phonological short term memory (STM) and semantic long term memory (LTM) representations distributed throughout the neocortex as patterns of sparse activations. This information is transferred to the hippocampus which converges upon the item closest to a stored pattern and outputs a response. Word pairs were learned from a study list, with one member of the pair serving as the cue at test. Unstudied words were also intermingled at test in order to provide an analogue of yes/no recognition tasks. Compared to incorrectly rejected studied items (misses) and correctly rejected (CR) unstudied items, correctly recalled items (hits) elicited increased responses in the left hippocampus and neocortical regions including the left inferior prefrontal cortex (LIPC), left mid lateral temporal cortex and inferior parietal cortex, consistent with predictions from the model. This network was very similar to that observed in yes/no recognition studies, supporting proposals that cued recall and item recognition involve common rather than separate mechanisms.
线索回忆和项目识别被视为标准的情景记忆检索任务。然而，只有后者的神经关联已通过功能磁共振成像（fMRI）进行了详细研究。我们采用了一种允许口头回应的事件相关fMRI实验设计，来检验来自线索回忆和项目识别自动联想模型的假设[查佩尔，M.，& 汉弗莱斯，M. S.（1994年）。用于稀疏表征的自动联想神经网络：分析及其在识别和线索回忆模型中的应用。《心理学评论》，101，103 - 128]。简而言之，该模型假设线索会引发一个语音短期记忆（STM）和语义长期记忆（LTM）表征网络，这些表征以稀疏激活模式分布在整个新皮层中。此信息被传输到海马体，海马体将其汇聚到最接近存储模式的项目上并输出一个反应。单词对是从一个学习列表中学习的，在测试时其中一对中的一个成员用作线索。未学习的单词在测试时也会混杂其中，以便提供一个是/否识别任务的类似物。与错误拒绝的已学习项目（漏报）和正确拒绝的（CR）未学习项目相比，正确回忆的项目（命中）在左侧海马体和新皮层区域（包括左侧前额叶下部皮质（LIPC）、左侧颞中外侧皮质和顶下皮质）引发了增强的反应，这与模型的预测一致。这个网络与在是/否识别研究中观察到的网络非常相似，支持了线索回忆和项目识别涉及共同而非单独机制的提议。
