The literature informing susceptible periods of exposure on children's neurodevelopment is limited. We evaluated the impacts of pre- and postnatal fine particulate matter (PM_2.5) exposure on children's cognitive and motor function among 1303 mother-child pairs in the Spanish INMA (Environment and Childhood) Study. Random forest models with temporal back extrapolation were used to estimate daily residential PM_2.5 exposures that we averaged across 1-week lags during the prenatal period and 4-week lags during the postnatal period. The McCarthy Scales of Children's Abilities (MSCA) were administered around 5 years to assess general cognitive index (GCI) and several subscales (verbal, perceptual-performance, memory, fine motor, gross motor). We applied distributed lag nonlinear models within the Bayesian hierarchical framework to explore periods of susceptibility to PM_2.5 on each MSCA outcome. Effect estimates were calculated per 5 μg/m³ increase in PM_2.5 and aggregated across adjacent statistically significant lags using cumulative β (β_cum) and 95% Credible Intervals (95%CrI). We evaluated interactions between PM_2.5 with fetal growth and child sex. We did not observe associations of PM_2.5 exposure with lower GCI scores. We found a period of susceptibility to PM_2.5 on fine motor scores in gestational weeks 1–9 (β_cum = −2.55, 95%CrI = −3.53,-1.56) and on gross motor scores in weeks 7–17 (β_cum = −2.27,95%CrI = −3.43,-1.11) though the individual lags for the latter were only borderline statistically significant. Exposure in gestational week 17 was weakly associated with verbal scores (β_cum = −0.17, 95%CrI = −0.26,-0.09). In the postnatal period (from age 0.5–1.2 years), we observed a window of susceptibility to PM_2.5 on lower perceptual-performance (β = −2.42, 95%CrI = −3.37,-1.46). Unexpected protective associations were observed for several outcomes with exposures in the later postnatal period. We observed no evidence of differences in susceptible periods by fetal growth or child sex. Preschool-aged children's motor function may be particularly susceptible to PM_2.5 exposures experienced in utero whereas the first year of life was identified as a period of susceptibility to PM_2.5 for children's perceptual-performance.

有关儿童神经发育的易受影响时期的文献有限。我们在西班牙 INMA（环境与童年）研究中评估了 1303 对母子中出生前和产后细颗粒物 (PM _2.5 ) 暴露对儿童认知和运动功能的影响。使用时间反向外推的随机森林模型来估计每日住宅 PM _2.5暴露量，我们对产前 1 周滞后和产后 4 周滞后进行平均。麦卡锡儿童能力量表 (MSCA) 在大约 5 岁时进行，以评估一般认知指数 (GCI) 和几个分量表（语言、知觉表现、记忆、精细运动、粗大运动）。我们应用贝叶斯分层框架内的分布式滞后非线性模型来探索每个 MSCA 结果对PM _{2.5的敏感期。PM 2.5}每增加5 μg/m ³计算效果估计值，并使用累积 β (β _cum)和 95% 可信区间 (95%CrI)在相邻的统计显着滞后期间进行汇总。我们评估了 PM _2.5与胎儿生长和儿童性别之间的相互作用。我们没有观察到 PM _2.5暴露与较低 GCI 分数之间的关联。我们发现妊娠第_1-9周的精细运动评分（β _cum  = -2.55, 95%CrI = -3.53,-1.56）和第 7-17 周的粗大运动评分（β _cum  = −2.27,95%CrI = −3.43,-1.11)，尽管后者的个体滞后仅具有统计学意义。妊娠第 17 周的暴露与言语评分微弱相关（β _cum  = -0.17，95%CrI = -0.26，-0.09）。在出生后时期（0.5-1.2 岁），我们观察到感知表现较低时对 PM _2.5的易感性窗口（β = -2.42，95%CrI = -3.37，-1.46）。观察到一些结果与产后后期暴露的意外保护关联。我们没有观察到胎儿生长或儿童性别导致易感期存在差异的证据。学龄前儿童的运动功能可能特别容易受到子宫内PM _2.5暴露的影响，而生命第一年被认为是儿童感知表现对PM _2.5的易感期。