Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Department of Clinical Psychology, Graduate School of Education, The University of Tokyo, Tokyo, Japan.
Brain Behav. 2018 Jun;8(6):e00980. doi: 10.1002/brb3.980. Epub 2018 Apr 24.
The genetic and environmental influences on prefrontal function in childhood are underinvestigated due to the difficulty of measuring prefrontal function in young subjects, for which near-infrared spectroscopy (NIRS) is a suitable functional neuroimaging technique that facilitates the easy and noninvasive measurement of blood oxygenation in the superficial cerebral cortices.
Using a two-channel NIRS arrangement, we measured changes in bilateral prefrontal blood oxygenation during a category version of the verbal fluency task (VFT) in 27 monozygotic twin pairs and 12 same-sex dizygotic twin pairs ages 5-17 years. We also assessed the participant's full-scale intelligence quotient (FIQ) and retrieved parental socioeconomic status (SES). Classical structured equation modeling was used to estimate the heritability.
The heritability of VFT-related brain activation was estimated to be 44% and 37% in the right and left prefrontal regions, respectively. We also identified a significant genetic contribution (74%) to FIQ, but did not to VFT task performance. Parental SES was not correlated with FIQ, task performance, or task-related prefrontal activation.
This finding provides further evidence that variance in prefrontal function has a genetic component since childhood and highlights brain function, as measured by NIRS, as a promising candidate for endophenotyping neurodevelopmental disorders.
由于难以在年幼的研究对象中测量前额叶功能，因此对儿童前额叶功能的遗传和环境影响的研究还不够深入。近红外光谱（NIRS）是一种合适的功能神经影像学技术，可方便地测量浅层大脑皮层的血氧变化，从而促进对其进行测量。
使用双通道 NIRS 排列，我们在 27 对同卵双胞胎和 12 对同性别异卵双胞胎（年龄在 5-17 岁之间）中测量了言语流畅性任务（VFT）的类别版本期间双侧前额叶的血氧变化。我们还评估了参与者的全量表智商（FIQ）并检索了父母的社会经济地位（SES）。经典结构方程模型用于估计遗传率。
VFT 相关脑激活的遗传率分别估计为右前额叶和左前额叶区域的 44％和 37％。我们还发现 FIQ 存在显著的遗传贡献（74％），但 VFT 任务表现则没有。父母 SES 与 FIQ，任务表现或与任务相关的前额叶激活均无相关性。
这项发现进一步证明了前额叶功能的变异性具有遗传成分，因为从儿童期开始，并且强调了由 NIRS 测量的大脑功能是神经发育障碍的内表型的有希望的候选者。
