School of Psychology, Shaanxi Provincial Key Research Center of Child Mental and Behavioral Health, Shaanxi Normal University, Xi'an, China.
School of Psychology, Northwest Normal University, Lanzhou, China.
Dev Sci. 2024 Nov;27(6):e13561. doi: 10.1111/desc.13561. Epub 2024 Aug 20.
Intra-individual response time variability (IIRTV) during cognitive performance is increasingly recognized as an important indicator of attentional control (AC) and related brain region function. However, what determinants contribute to preschoolers' IIRTV received little attention. The present study explored the interaction of dopaminergic polygenic composite score (DPCS) and the parent-child relationship in relation to preschoolers' IIRTV. In the initial sample, 452 preschoolers (M age = 5.17, SD = 0.92) participated in the study. The modified Flanker task was used to evaluate children's IIRTV and their parents were requested to complete the Parent-Child Relationship Scale to assess the parent-child relationship (closeness/conflict). DNA data were extracted from children's saliva samples, and a DPCS was created by the number of COMT, DAT1, and DRD2 alleles associated with lower dopamine levels. Results showed that DPCS significantly interacted with the parent-child closeness to impact preschoolers' IIRTV. Specifically, preschoolers with higher DPCS exhibited lower IIRTV under higher levels of the parent-child closeness, and greater IIRTV under lower levels of the parent-child closeness compared to those with lower DPCS, which supported the differential susceptibility theory (DST). A direct replication attempt with 280 preschoolers (M age = 4.80, SD = 0.86) was conducted to investigate whether the results were in accordance with our exploratory outcomes. The interactive effect of DPCS and the parent-child closeness on IIRTV was confirmed. Additionally, the significant interactive effect of DPCS and the parent-child conflict on IIRTV was found in the replication study. The findings indicate that preschoolers' IIRTV, as an indicator of AC and related brain region function, is influenced by the interactions of dopaminergic genotypes and the parent-child relationship. RESEARCH HIGHLIGHTS: We investigated the Gene × Environment mechanism to underline the intra-individual response time variability as an indicator of attentional control (AC) in Chinese preschoolers. Dopaminergic polygenic composite score (COMT, DAT1, and DRD2) interacted with the parent-child relationship to predict preschoolers' intra-individual reaction time variability. A direct replication attempt has been conducted, and the results were in accordance with our exploratory outcomes, which increased the credibility of the present findings. The findings highlight the importance of considering precursors, including polygenic and environmental factors, which contribute to the development of early cognitive performance such as AC.
个体内反应时变异性（IIRTV）在认知表现中越来越被认为是注意力控制（AC）和相关脑区功能的重要指标。然而，对于学龄前儿童的 IIRTV 有哪些决定因素，这方面的研究还很少。本研究探讨了多巴胺多基因复合评分（DPCS）与亲子关系之间的相互作用，以及它们与学龄前儿童 IIRTV 的关系。在最初的样本中，452 名学龄前儿童（M 年龄=5.17，SD=0.92）参与了这项研究。采用改良的 Flanker 任务评估儿童的 IIRTV，要求其父母完成亲子关系量表，以评估亲子关系（亲密/冲突）。从儿童的唾液样本中提取 DNA 数据，并根据与较低多巴胺水平相关的 COMT、DAT1 和 DRD2 等位基因的数量创建 DPCS。结果表明，DPCS 与亲子亲密程度显著相互作用，影响学龄前儿童的 IIRTV。具体来说，与 DPCS 较低的儿童相比，DPCS 较高且亲子关系较亲密的儿童，其 IIRTV 较低，而 DPCS 较低且亲子关系较不亲密的儿童，其 IIRTV 较高，这支持了差异易感性理论（DST）。对 280 名学龄前儿童（M 年龄=4.80，SD=0.86）进行了直接复制尝试，以检验我们的探索性结果是否一致。结果证实了 DPCS 与亲子亲密程度对 IIRTV 的交互作用。此外，在复制研究中还发现了 DPCS 与亲子冲突对 IIRTV 的显著交互作用。研究结果表明，作为 AC 和相关脑区功能的指标，学龄前儿童的 IIRTV 受到多巴胺基因型和亲子关系相互作用的影响。研究亮点：我们研究了基因×环境机制，以强调个体内反应时变异性作为注意力控制（AC）的指标。多巴胺多基因复合评分（COMT、DAT1 和 DRD2）与亲子关系相互作用，预测学龄前儿童的个体内反应时变异性。进行了直接复制尝试，结果与我们的探索性结果一致，提高了本研究发现的可信度。研究结果强调了考虑多基因和环境因素等前体对早期认知表现（如 AC）发展的重要性。
