Yunnan Key Laboratory of Primate Biomedicine Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China.
Autism Res. 2019 Nov;12(11):1585-1597. doi: 10.1002/aur.2189. Epub 2019 Aug 7.
The cognitive phenotypes of Rett syndrome (RTT) remain unclarified compared with the well-defined genetic etiology. Recent clinical studies suggest the eye-tracking method as a promising avenue to quantify the visual phenotypes of the syndrome. The present study explored various aspects of visual attention of the methyl-CpG-binding protein 2 gene mutant RTT monkeys with the eye-tracking procedure. Comprehensive testing paradigms, including social valence comparison (SVC), visual paired comparison (VPC), and social recognition memory (SRM), were utilized to investigate their attentional features to social stimuli with differential valence, the novelty preferences, and short-term recognition memory, respectively. To explore the neurobiological mechanisms underlying the eye-tracking findings, we assessed changes of the brain subregion volumes and neurotransmitter concentrations. Compared with control monkeys, RTT monkeys demonstrated increased viewing on the more salient stare faces than profile faces in the SVC test, and increased viewing on the whole presented images composed of monkey faces in the VPC and SRM tests. Brain imaging revealed reduced bilateral occipital gyrus in RTT monkeys. The exploratory neurotransmitter analyses revealed no significant changes of various neurotransmitter concentrations in the cerebrospinal fluid and blood of RTT monkeys. The eye-tracking results suggested social-valence-related increased attention in RTT monkeys, supplementing the cognitive phenotypes associated with the syndrome. Further investigations from broader perspectives are required to uncover the underlying neurobiological mechanisms. Autism Res 2019, 00: 1-13. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Altered expressions of the methyl-CpG-binding protein 2 (MECP2) gene are usually associated with neurodevelopmental disorders, such as autism spectrum disorders, Rett syndrome (RTT), and so forth. The present eye-tracking study found social-valence-related increased attention in our firstly established MECP2 mutant RTT monkeys. The novel findings supplement the cognitive phenotypes and potentially benefit the behavioral interventions of the RTT syndrome.
雷特综合征（RTT）的认知表型与明确的遗传病因相比仍不清楚。最近的临床研究表明，眼动追踪方法是量化该综合征视觉表型的一种很有前途的途径。本研究通过眼动追踪程序探索了 MECP2 基因突变 RTT 猴的各种视觉注意力方面。综合测试范式，包括社会效价比较（SVC）、视觉配对比较（VPC）和社会识别记忆（SRM），分别用于研究它们对具有不同效价的社会刺激、新颖偏好和短期识别记忆的注意力特征。为了探索眼动追踪结果的神经生物学机制，我们评估了脑区体积和神经递质浓度的变化。与对照组猴子相比，RTT 猴子在 SVC 测试中注视更显著的凝视面孔而不是侧视面孔，在 VPC 和 SRM 测试中注视整个由猴子面孔组成的呈现图像。脑成像显示 RTT 猴子双侧枕叶回体积减少。探索性神经递质分析显示 RTT 猴子脑脊液和血液中各种神经递质浓度无显著变化。眼动追踪结果表明 RTT 猴子存在与社会效价相关的注意力增加，补充了与该综合征相关的认知表型。需要从更广泛的角度进行进一步研究，以揭示潜在的神经生物学机制。自闭症研究 2019 年，00：1-13。©2019 自闭症研究国际协会，威利期刊，公司。 要点总结：甲基-CpG 结合蛋白 2（MECP2）基因的异常表达通常与神经发育障碍有关，如自闭症谱系障碍、雷特综合征（RTT）等。本眼动追踪研究首次发现 MECP2 基因突变 RTT 猴存在与社会效价相关的注意力增加。新发现补充了认知表型，可能有助于 RTT 综合征的行为干预。
