Department of Psychiatry and Psychotherapy III, University of Ulm, Ulm, Germany.
Int J Neurosci. 2010 Jan;120(1):40-50. doi: 10.3109/00207450903290516.
Using a parametric version of a modified item-recognition paradigm with three different load levels and by means of event-related functional magnetic resonance imaging, this study tested the hypothesis that cerebral activation associated with intratrial proactive interference (PI) during working memory retrieval is influenced by increased context processing. We found activation of left BA 45 during interference trials across all levels of cognitive processing, and left lateralized activation of the dorsolateral prefrontal cortex (DLPFC, BA 9/46) and the frontopolar cortex (FPC, BA 10) with increasing contextual load. Compared with high susceptibility to PI, low susceptibility was associated with activation of the left DLPFC. These results suggest that an intratrial PI effect can be modulated by increasing context processing of a transiently relevant stimulus set. Moreover, PI resolution associated with increasing context load involves multiple prefrontal regions including the ventro- and dorsolateral prefrontal cortex as well as frontopolar brain areas. Furthermore, low susceptibility to PI might be influenced by increased executive control exerted by the DLPFC.
本研究采用改良项目识别范式的参数版本，结合三种不同的负荷水平，通过事件相关功能磁共振成像，检验了以下假设：在工作记忆检索过程中，与心房内前摄干扰（PI）相关的大脑激活受到增加的上下文处理的影响。我们发现，在所有认知处理水平的干扰试验中，左额下回（BA 45）都有激活，随着上下文负荷的增加，背外侧前额叶皮层（DLPFC，BA 9/46）和额极皮层（FPC，BA 10）也出现了左侧偏侧化激活。与高 PI 易感性相比，低 PI 易感性与左 DLPFC 的激活有关。这些结果表明，心房内 PI 效应可以通过增加对瞬态相关刺激集的上下文处理来调节。此外，与增加上下文负荷相关的 PI 分辨率涉及多个前额叶区域，包括腹侧和背外侧前额叶皮层以及额极脑区。此外，DLPFC 施加的执行控制增加可能会影响到 PI 的低易感性。
