Hodel Amanda S, Brumbaugh Jane E, Morris Alyssa R, Thomas Kathleen M
Institute of Child Development, University of Minnesota, USA.
Stead Family Department of Pediatrics, University of Iowa Hospitals and Clinics, USA.
Dev Sci. 2016 Mar;19(2):221-34. doi: 10.1111/desc.12307. Epub 2015 Apr 14.
Interest in monitoring long-term neurodevelopmental outcomes of children born moderate-to-late preterm (32-36 weeks gestation) is increasing. Moderate-to-late preterm birth has a negative impact on academic achievement, which may relate to differential development of executive function (EF). Prior studies reporting deficits in EF in preterm children have almost exclusively assessed EF in affectively neutral contexts in high-risk preterm children (< 32 weeks gestation). Disrupted function in motivational or emotionally charged contexts (hot EF) following preterm birth remains uninvestigated, despite evidence that preterm children show differential development of neural circuitry subserving hot EF, including reduced orbitofrontal cortex volume. The present study is the first to examine whether low-risk, healthy children born moderate-to-late preterm exhibit impairments in the development of hot EF. Preterm children at age 4.5 years were less likely to choose larger, delayed rewards across all levels of reward magnitude on a delay discounting task using tangible rewards, but performed more similarly to their full-term peers on a delay aversion task involving abstract rewards and on measures of cool EF. The relationship between gestational age at birth and selection of delayed rewards extended across the entire gestational age range of the sample (32-42 weeks), and remained significant after controlling for intelligence and processing speed. Results imply that there is not a finite cut-off point at which children are spared from potential long-term neurodevelopmental effects of PT birth. Further investigation of reward processing and hot EF in individuals with a history of PT birth is warranted given the susceptibility of prefrontal cortex development to early environmental variations.
对中度至晚期早产儿（妊娠32 - 36周）长期神经发育结局进行监测的关注度日益增加。中度至晚期早产对学业成绩有负面影响，这可能与执行功能（EF）的差异发展有关。先前报道早产儿EF缺陷的研究几乎都仅在高风险早产儿（妊娠< 32周）的情感中性情境中评估EF。尽管有证据表明早产儿在服务于热EF的神经回路方面存在差异发展，包括眶额皮质体积减小，但早产出生后在动机性或情绪激动情境中的功能紊乱（热EF）仍未得到研究。本研究首次探讨出生时为中度至晚期早产的低风险健康儿童在热EF发展方面是否存在损害。4.5岁的早产儿在使用有形奖励的延迟折扣任务中，在所有奖励幅度水平上选择更大、延迟奖励的可能性较小，但在涉及抽象奖励的延迟厌恶任务和冷EF测量方面，其表现与足月儿更为相似。出生时的胎龄与延迟奖励选择之间的关系在样本的整个胎龄范围（32 - 42周）内都存在，并且在控制智力和处理速度后仍然显著。结果表明，不存在一个特定的临界点，超过该点儿童就能免受早产出生潜在的长期神经发育影响。鉴于前额叶皮质发育对早期环境变化的敏感性，对有早产出生史的个体的奖励处理和热EF进行进一步研究是有必要的。
