科研人员把儿童和青少年的大脑发育与新生儿出生体重联系了起来。科研人员已经越来越多地认识到认知、行为和心理健康特征可以追溯到胎儿发育，但是人们对胎儿生长的正常波动和之后的生命阶段的大脑发育的关系还知之甚少。
Kristine Walhovd及其同事使用来自对628名健康美国儿童和青少年所作的一项多中心研究的信息将个体出生体重和大脑结构、区域以及体积进行了比较。这组作者发现即便在控制了年龄、性别、家庭收入和遗传世系之后，婴儿期体重更重的儿童比体重较轻的健康婴儿在多个区域的大脑表面积更大，而且大脑总体积更大。看上去与出生体重最高度相关的某些大脑区域是负责解决认知冲突的一个网络的部分。
为了确定这些结果差异是否影响认知功能，这组作者把出生体重和大脑结构数据与一个标准的认知对照测试进行了比较。尽管这个比较表明大脑功能和相关大脑区域之间存在一种联系，这组作者没有发现出生体重和认知功能之间的联系。（生物谷Bioon.com）
doi:10.1073/pnas.1208180109
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PMID:
Long-term influence of normal variation in neonatal characteristics on human brain development
Kristine B. Walhovd, Anders M. Fjell, Timothy T. Brown, Joshua M. Kuperman, Yoonho Chung, Donald J. Hagler, Jr, J. Cooper Roddey, Matthew Erhart, Connor McCabe, Natacha Akshoomoff, David G. Amaral, Cinnamon S. Bloss, Ondrej Libiger, Nicholas J. Schork, Burcu F. Darst, B. J. Casey, Linda Chang, Thomas M. Ernst, Jean Frazier, Jeffrey R. Gruen, Walter E. Kaufmann, Sarah S. Murray, Peter van Zijl, Stewart Mostofsky, Anders M. Dale, and for the Pediatric Imaging, Neurocognition, and Genetics Study
Familiarity to the mother and the novelty afforded by the postnatal environment are two contrasting sources of neonatal influence. One hypothesis regarding their relationship is the maternal modulation hypothesis, which predicts that the same neonatal stimulation may have different effects depending on the maternal context. Here we tested this hypothesis using physical development, indexed by body weight, as an endpoint and found that, among offspring of mothers with a high initial swim-stress–induced corticosterone (CORT) response, neonatal novelty exposure induced an enhancement in early growth, and among offspring with mothers of a low initial CORT response, the same neonatal stimulation induced an impairment. At an older age, a novelty-induced increase in body weight was also found among offspring of mothers with high postnatal care reliability and a novelty-induced reduction found among offspring of mothers with low care reliability. These results support a maternal modulation of early stimulation effects on physical development and demonstrate that the maternal influence originates from multiple instead of any singular sources. These results (i) significantly extend the findings of maternal modulation from the domain of cognitive development to the domain of physical development; (ii) offer a unifying explanation for a previously inconsistent literature regarding early stimulation effects on body weight; and (iii) highlight the notion that the early experience effect involves no causal primacy but higher order interactions among the initial triggering events and subsequent events involving a multitude of maternal and nonmaternal influences.
