Kim Hongkeun, Cabeza Roberto
Department of Rehabilitation Psychology, Daegu University, Jillyang, Gyeongsan, Gyeongbuk 712-714, South Korea.
Brain Res. 2009 Jul 28;1282:103-13. doi: 10.1016/j.brainres.2009.05.080. Epub 2009 Jun 6.
The goal of the present functional magnetic resonance imaging (fMRI) study was to investigate whether and to what extent brain regions involved in high-confidence recognition (HCR) versus low-confidence recognition (LCR) overlap or separate from each other. To this end, we performed conjunction analyses involving activations elicited during high-confidence hit, low-confidence hit, and high-confidence correct rejection responses. The analyses yielded 3 main findings. First, sensory/perceptual and associated posterior regions were common to HCR and LCR, indicating contribution of these regions to both HCR and LCR activity. This finding may help explain why these regions are among the most common in functional neuroimaging studies of episodic retrieval. Second, medial temporal lobe (MTL) and associated midline regions were associated with HCR, possibly reflecting recollection-related processes, whereas specific prefrontal cortex (PFC) regions were associated with LCR, possibly reflecting executive control processes. This finding is consistent with the notion that the MTL and PFC networks play complementary roles during episodic retrieval. Finally, within posterior parietal cortex, a dorsal region was associated with LCR, possibly reflecting top-down attentional processes, whereas a ventral region was associated with HCR, possibly reflecting bottom-up attentional processes. This finding may help explain why functional neuroimaging studies have found diverse parietal effects during episodic retrieval. Taken together, our findings provide strong evidence that HCR versus LCR, and by implication, recollection versus familiarity processes, are represented in common as well as specific brain regions.
本功能磁共振成像（fMRI）研究的目的是调查参与高置信度识别（HCR）与低置信度识别（LCR）的脑区在何种程度上相互重叠或分离。为此，我们进行了联合分析，涉及高置信度命中、低置信度命中以及高置信度正确拒绝反应期间引发的激活。分析得出了3个主要发现。首先，感觉/知觉及相关的后部区域在HCR和LCR中是共同的，这表明这些区域对HCR和LCR活动均有贡献。这一发现可能有助于解释为什么这些区域是情景记忆检索功能神经影像学研究中最常见的区域之一。其次，内侧颞叶（MTL）及相关的中线区域与HCR相关，可能反映与回忆相关的过程，而特定的前额叶皮质（PFC）区域与LCR相关，可能反映执行控制过程。这一发现与MTL和PFC网络在情景记忆检索过程中发挥互补作用的观点一致。最后，在顶叶后皮质内，一个背侧区域与LCR相关，可能反映自上而下的注意过程，而一个腹侧区域与HCR相关，可能反映自下而上的注意过程。这一发现可能有助于解释为什么功能神经影像学研究在情景记忆检索过程中发现了不同的顶叶效应。综上所述，我们的研究结果提供了强有力的证据，表明HCR与LCR，以及由此暗示的回忆与熟悉过程，在共同的以及特定的脑区中均有体现。
