Ross Robert S, Medrano Paolo, Boyle Kaitlin, Smolen Andrew, Curran Tim, Nyhus Erika
University of New Hampshire, Psychology Department, Durham, NH, USA; University of New Hampshire, Neuroscience and Behavior Program, Durham, NH, USA.
University of New Hampshire, Psychology Department, Durham, NH, USA.
Neuropsychologia. 2015 Nov;78:95-107. doi: 10.1016/j.neuropsychologia.2015.09.028. Epub 2015 Sep 28.
Recognition memory is defined as the ability to recognize a previously encountered stimulus and has been associated with spatially and temporally distinct event-related potentials (ERPs). Allelic variations of the serotonin transporter gene (SLC6A4) have recently been shown to impact memory performance. Common variants of the serotonin transporter-linked polymorphic region (5HTTLPR) of the SLC6A4 gene result in long (l) and short (s) allelic variants with carriers of the s allele having lowered transcriptional efficiency. Thus, the current study examines the effects polymorphisms of the SLC6A4 gene have on performance and ERP amplitudes commonly associated with recognition memory. Electroencephalogram (EEG), genetic, and behavioral data were collected from sixty participants as they performed an item and source memory recognition task. In both tasks, participants studied and encoded 200 words, which were then mixed with 200 new words during retrieval. Participants were monitored with EEG during the retrieval portion of each memory task. EEG electrodes were grouped into four ROIs, left anterior superior, right anterior superior, left posterior superior, and right posterior superior. ERP mean amplitudes during hits in the item and source memory task were compared to correctly recognizing new items (correct rejections). Results show that s-carriers have decreased mean hit amplitudes in both the right anterior superior ROI 1000-1500ms post stimulus during the source memory task and the left anterior superior ROI 300-500ms post stimulus during the item memory task. These results suggest that individual differences due to genetic variation of the serotonin transporter gene influences recognition memory.
识别记忆被定义为识别先前遇到的刺激的能力，并与空间和时间上不同的事件相关电位（ERP）有关。血清素转运体基因（SLC6A4）的等位基因变异最近已被证明会影响记忆表现。SLC6A4基因的血清素转运体相关多态性区域（5HTTLPR）的常见变异会导致长（l）和短（s）等位基因变异，s等位基因的携带者转录效率较低。因此，本研究考察了SLC6A4基因多态性对通常与识别记忆相关的表现和ERP波幅的影响。在60名参与者执行项目和来源记忆识别任务时，收集他们的脑电图（EEG）、基因和行为数据。在这两项任务中，参与者学习并编码200个单词，并在检索时与200个新单词混合。在每个记忆任务的检索部分，用EEG对参与者进行监测。EEG电极被分为四个感兴趣区域，左前上、右前上、左后上和右后上。将项目和来源记忆任务中命中时的ERP平均波幅与正确识别新单词（正确拒绝）进行比较。结果表明，在来源记忆任务中，s等位基因携带者在刺激后1000 - 1500毫秒的右前上感兴趣区域以及项目记忆任务中刺激后300 - 500毫秒的左前上感兴趣区域的平均命中波幅降低。这些结果表明，血清素转运体基因的遗传变异导致的个体差异会影响识别记忆。
