Gabrys Robert L, Dixon Kaylyn, Anisman Hymie
Department of Neuroscience, Carleton University, Ottawa, ON, Canada.
Front Behav Neurosci. 2017 Dec 8;11:241. doi: 10.3389/fnbeh.2017.00241. eCollection 2017.
Cognitive flexibility plays an important role in an individual's ability to adapt to a continuously changing environment and is considered central to goal-oriented behavior. Accordingly, increasing attention has been devoted to understanding the factors, including genetic and early life experiences, which might contribute to individual differences in this ability. In the present investigation, we examined the contribution of the BDNF polymorphism to cognitive flexibility, as assessed by set-shifting ability on the Wisconsin Card Sorting Task (WCST), and whether this polymorphism moderated the relation between trauma experiences (including type and timing of trauma occurrence) and cognitive flexibility. Among undergraduate students ( = 239), greater frequency of total traumas experienced prior to the age 5 was associated with greater difficulties in set-shifting (as indexed by more frequent perseverative errors on the WCST) among individuals carrying the allele of the BDNF polymorphism, but not those who were homozygotes. By contrast, total traumas experienced between the age of 6 to 12 and 13 to 18 were not related to set-shifting ability, and these relations were not moderated by BDNF genotype. Moreover, greater frequency of general traumas and emotional abuse was associated with set-shifting difficulties for both male and female allele carriers, but not homozygotes. In contrast, physical punishment was related to difficulties in set-shifting, but only among male carriers, an effect that was likely attributed to greater frequency of this form of trauma among males. The present findings suggest that the relationship between early life trauma and later-life cognitive flexibility might depend on the presence of the BDNF polymorphism as well as the development stage at which the trauma has occurred. Moreover, the present investigation provides further understanding into the factors (i.e., genetic and early life experiences) that might be associated with individual differences in cognitive functioning and goal-directed behaviors, such as problem-solving and decision-making.
认知灵活性在个体适应不断变化的环境的能力中起着重要作用，并且被认为是目标导向行为的核心。因此，人们越来越关注理解包括遗传和早期生活经历在内的可能导致这种能力个体差异的因素。在本研究中，我们考察了脑源性神经营养因子（BDNF）多态性对认知灵活性的贡献（通过威斯康星卡片分类任务（WCST）中的转换能力来评估），以及这种多态性是否调节了创伤经历（包括创伤发生的类型和时间）与认知灵活性之间的关系。在本科生（n = 239）中，5岁之前经历的总创伤频率越高，携带BDNF多态性的缬氨酸（Val）等位基因的个体在转换任务中遇到的困难就越大（以WCST中更频繁的持续性错误为指标），但纯合子个体则不然。相比之下，6至12岁和13至18岁之间经历的总创伤与转换能力无关，并且这些关系不受BDNF基因型的调节。此外，无论是男性还是女性缬氨酸等位基因携带者，一般创伤和情感虐待的频率越高，与转换困难相关，但纯合子个体则不然。相比之下，体罚与转换困难有关，但仅在男性缬氨酸携带者中如此，这种影响可能归因于男性中这种创伤形式的频率更高。本研究结果表明，早期生活创伤与后期认知灵活性之间的关系可能取决于BDNF缬氨酸多态性的存在以及创伤发生的发育阶段。此外，本研究进一步深入了解了可能与认知功能和目标导向行为（如解决问题和决策）的个体差异相关的因素（即遗传和早期生活经历）。
