科研人員把兒童和青少年的大腦發(fā)育與新生兒出生體重聯(lián)系了起來?？蒲腥藛T已經(jīng)越來越多地認識到認知,、行為和心理健康特征可以追溯到胎兒發(fā)育,，但是人們對胎兒生長的正常波動和之后的生命階段的大腦發(fā)育的關系還知之甚少。
Kristine Walhovd及其同事使用來自對628名健康美國兒童和青少年所作的一項多中心研究的信息將個體出生體重和大腦結構,、區(qū)域以及體積進行了比較,。這組作者發(fā)現(xiàn)即便在控制了年齡、性別,、家庭收入和遺傳世系之后,，嬰兒期體重更重的兒童比體重較輕的健康嬰兒在多個區(qū)域的大腦表面積更大，而且大腦總體積更大,?？瓷先ヅc出生體重最高度相關的某些大腦區(qū)域是負責解決認知沖突的一個網(wǎng)絡的部分。
為了確定這些結果差異是否影響認知功能,，這組作者把出生體重和大腦結構數(shù)據(jù)與一個標準的認知對照測試進行了比較,。盡管這個比較表明大腦功能和相關大腦區(qū)域之間存在一種聯(lián)系，這組作者沒有發(fā)現(xiàn)出生體重和認知功能之間的聯(lián)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.
