Center for Vital Longevity, University of Texas at Dallas, 1600 Viceroy Drive, Dallas, TX 75235, USA.
J Cogn Neurosci. 2012 May;24(5):1055-68. doi: 10.1162/jocn_a_00129. Epub 2011 Aug 31.
ERPs were recorded from samples of young (18-29 years) and older (63-77 years) participants while they performed a modified "remember-know" recognition memory test. ERP correlates of familiarity-driven recognition were obtained by contrasting the waveforms elicited by unrecollected test items accorded "confident old" and "confident new" judgments. Correlates of recollection were identified by contrasting the ERPs elicited by items accorded "remember" and confident old judgments. Behavioral analyses revealed lower estimates of both recollection and familiarity in older participants than in young participants. The putative ERP correlate of recollection-the "left parietal old-new effect"-was evident in both age groups, although it was slightly but significantly smaller in the older sample. By contrast, the putative ERP correlate of familiarity-the "midfrontal old-new effect"-could be identified in young participants only. This age-related difference in the sensitivity of ERPs to familiarity was also evident in subgroups of young and older participants, in whom familiarity-based recognition performance was equivalent. Thus, the inability to detect a reliable midfrontal old-new effect in older participants was not a consequence of an age-related decline in the strength of familiarity. These findings raise the possibility that familiarity-based recognition memory depends upon qualitatively different memory signals in older and young adults.
事件相关电位(ERPs)是从年轻(18-29 岁)和年长(63-77 岁)参与者中记录的样本中获得的,这些参与者在进行修改后的“记得-知道”识别记忆测试时进行了操作。通过对比给予“自信旧”和“自信新”判断的未回忆测试项目的波形,获得了熟悉度驱动识别的 ERP 相关性。通过对比给予“记得”和自信旧判断的项目的 ERP,确定了回忆的相关性。行为分析显示,年长参与者的回忆和熟悉度估计值均低于年轻参与者。在两个年龄组中都可以发现被认为是回忆的 ERP 相关性——“左顶叶新旧效应”,尽管在年长组中略小但具有显著意义。相比之下,被认为是熟悉度的 ERP 相关性——“中额叶新旧效应”——仅在年轻参与者中可以识别。这种与年龄相关的 ERPs 对熟悉度的敏感性差异,在熟悉度基础上的识别表现相当的年轻和年长参与者的亚组中也很明显。因此,在年长参与者中无法检测到可靠的中额叶新旧效应并不是熟悉度的年龄相关下降的结果。这些发现提出了这样一种可能性,即基于熟悉度的识别记忆依赖于年长和年轻成年人中不同质量的记忆信号。