Sohn Myeong-Ho, Goode Adam, Stenger V Andrew, Jung Kwan-Jin, Carter Cameron S, Anderson John R
Department of Psychology, Carnegie Mellon University, 342C Baker Hall, Pittsburgh, PA 15213, USA.
Neuroimage. 2005 Mar;25(1):21-33. doi: 10.1016/j.neuroimage.2004.11.001. Epub 2005 Jan 25.
ACT-R (Anderson, J.R., et al., 2003. An information-processing model of the BOLD response in symbol manipulation tasks. Psychon. Bull. Rev. 10, 241-261) relates the inferior dorso-lateral prefrontal cortex to a retrieval buffer that holds information retrieved from memory and the posterior parietal cortex to an imaginal buffer that holds problem representations. Because the number of changes in a problem representation is not necessarily correlated with retrieval difficulties, it is possible to dissociate prefrontal-parietal activations. In two fMRI experiments, we examined this dissociation using the fan effect paradigm. Experiment 1 compared a recognition task, in which representation requirement remains the same regardless of retrieval difficulty, with a recall task, in which both representation and retrieval loads increase with retrieval difficulty. In the recognition task, the prefrontal activation revealed a fan effect but not the parietal activation. In the recall task, both regions revealed fan effects. In Experiment 2, we compared visually presented stimuli and aurally presented stimuli using the recognition task. While only the prefrontal region revealed the fan effect, the activation patterns in the prefrontal and the parietal region did not differ by stimulus presentation modality. In general, these results provide support for the prefrontal-parietal dissociation in terms of retrieval and representation and the modality-independent nature of the information processed by these regions. Using ACT-R, we also provide computational models that explain patterns of fMRI responses in these two areas during recognition and recall.
ACT-R（安德森，J.R.等人，2003年。符号操作任务中BOLD反应的信息处理模型。《心理通报与评论》10，241 - 261）将背外侧前额叶皮层下部与一个保存从记忆中检索到的信息的检索缓冲器相关联，将顶叶后部皮层与一个保存问题表征的想象缓冲器相关联。由于问题表征中的变化数量不一定与检索难度相关，所以有可能区分前额叶 - 顶叶的激活情况。在两项功能磁共振成像实验中，我们使用扇形效应范式研究了这种区分。实验1将一个识别任务（其中无论检索难度如何，表征要求保持不变）与一个回忆任务进行了比较，在回忆任务中，表征和检索负荷都随着检索难度的增加而增加。在识别任务中，前额叶激活显示出扇形效应，但顶叶激活未显示。在回忆任务中，两个区域都显示出扇形效应。在实验2中，我们使用识别任务比较了视觉呈现的刺激和听觉呈现的刺激。虽然只有前额叶区域显示出扇形效应，但前额叶和顶叶区域的激活模式在刺激呈现方式上没有差异。总体而言，这些结果为前额叶 - 顶叶在检索和表征方面的区分以及这些区域处理信息的模态独立性提供了支持。使用ACT-R，我们还提供了计算模型，解释了在识别和回忆过程中这两个区域功能磁共振成像反应的模式。
