Saliasi Emi, Geerligs Linda, Lorist Monicque M, Maurits Natasha M
Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; BCN-NeuroImaging Center, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
Department of Experimental Psychology, University of Groningen, Groningen, The Netherlands; BCN-NeuroImaging Center, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
PLoS One. 2014 Jun 9;9(6):e99250. doi: 10.1371/journal.pone.0099250. eCollection 2014.
To investigate which neural correlates are associated with successful working memory performance, fMRI was recorded in healthy younger and older adults during performance on an n-back task with varying task demands. To identify functional networks supporting working memory processes, we used independent component analysis (ICA) decomposition of the fMRI data. Compared to younger adults, older adults showed a larger neural (BOLD) response in the more complex (2-back) than in the baseline (0-back) task condition, in the ventral lateral prefrontal cortex (VLPFC) and in the right fronto-parietal network (FPN). Our results indicated that a higher BOLD response in the VLPFC was associated with increased performance accuracy in older adults, in the more complex task condition. This 'BOLD-performance' relationship suggests that the neural correlates linked with successful performance in the older adults are related to specific working memory processes present in the complex but not in the baseline task condition [corrected].Furthermore, the selective presence of this relationship in older but not in younger adults suggests that increased neural activity in the VLPFC serves a compensatory role in the aging brain which benefits task performance in the elderly.
为了研究哪些神经关联与成功的工作记忆表现相关，在健康的年轻人和老年人执行具有不同任务要求的n-back任务时，记录了功能磁共振成像（fMRI）。为了识别支持工作记忆过程的功能网络，我们对fMRI数据进行了独立成分分析（ICA）分解。与年轻人相比，老年人在更复杂的（2-back）任务条件下，比在基线（0-back）任务条件下，在腹侧前额叶皮层（VLPFC）和右侧额顶网络（FPN）中表现出更大的神经（血氧水平依赖，BOLD）反应。我们的结果表明，在更复杂的任务条件下，VLPFC中较高的BOLD反应与老年人表现准确性的提高相关。这种“BOLD-表现”关系表明，与老年人成功表现相关的神经关联与复杂任务条件下而非基线任务条件下存在的特定工作记忆过程有关[已修正]。此外，这种关系在老年人中选择性存在而在年轻人中不存在，这表明VLPFC中神经活动的增加在衰老大脑中起到了补偿作用，有利于老年人的任务表现。
