Abstract:Temperament growth has been examined in infancy, but the spectrum of reactive and regulatory dimensions was not previously considered. We evaluated linear and nonlinear growth trajectories for overarching factors and fine-grained indicators of infant temperament obtained via parent report (N = 143) at 4, 6, 8, 10, and 12 months of age. Contributions of infant sex, family socioeconomic status, maternal stress, depression, and anxiety to trajectory parameters were also considered. Results indicated nonlinear trajectories as best fitting for negative emotionality (quadratic model) and regulatory capacity/orienting (piecewise), with a linear model deemed most optimal for positive affectivity/surgency. However, models of best fit associated with the overarching temperament factors were not consistently representative of the underlying fine-grained dimensions. Results indicate primarily nonlinear growth of infant temperament across the first year of life and support the importance of fine-grained level analyses. Effects of infant sex, socioeconomic status, maternal stress, anxiety and depression symptoms were generally consistent with hypotheses.

中文翻译：

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婴儿的气质性增长：人口统计学，母体症状和对总体和细粒度尺寸的压力贡献

摘要：婴儿期的气质生长已被检查过，但以前没有考虑反应性和调节性的范围。我们通过4、6、8、10和12个月的父母报告（N = 143）评估了线性和非线性增长轨迹的总体因素和婴儿气质的细粒度指标。还考虑了婴儿性别，家庭社会经济地位，母亲压力，抑郁和焦虑对轨迹参数的影响。结果表明，非线性轨迹最适合负面情绪（二次模型）和调节能力/方向（分段），而线性模型被认为对于正面情感/突发事件最合适。然而，与总体气质因子相关的最佳拟合模型并不能始终代表潜在的细粒度。结果表明，在出生的第一年中，婴儿气质主要呈非线性增长，并支持进行细粒度水平分析的重要性。婴儿性别，社会经济地位，产妇压力，焦虑和抑郁症状的影响通常与假设相符。