Lester B M, Corwin M J, Sepkoski C, Seifer R, Peucker M, McLaughlin S, Golub H L
Brown University Program in Medicine, Providence, RI.
Child Dev. 1991 Aug;62(4):694-705. doi: 10.1111/j.1467-8624.1991.tb01563.x.
The effects of fetal cocaine exposure on newborn cry characteristics were studied in 80 cocaine-exposed and 80 control infants. The groups were stratified to be similar on maternal demographic characteristics and maternal use of other illegal substances and alcohol during pregnancy. The hypothesis was that excitable cry characteristics were related to the direct effects of cocaine, while depressed cry characteristics were related to the indirect effects of cocaine secondary to low birthweight. Structural equation modeling (EQS) showed direct effects of cocaine on cries with a longer duration, higher fundamental frequency, and a higher and more variable first formant frequency. Indirect effects of cocaine secondary to low birthweight resulted in cries with a longer latency, fewer utterances, lower amplitude, and more dysphonation. Cocaine-exposed infants had a lower birthweight, shorter length, and smaller head circumference than the unexposed controls. Findings were consistent with the notion that 2 neurobehavioral syndromes, excitable and depressed, can be described in cocaine-exposed infants, and that these 2 syndromes are due, respectively, to direct neurotoxic effects and indirect effects secondary to intrauterine growth retardation.
对80名暴露于可卡因的婴儿和80名对照婴儿进行了研究，以探讨胎儿暴露于可卡因对新生儿哭声特征的影响。根据母亲的人口统计学特征以及孕期母亲使用其他非法药物和酒精的情况，将两组进行分层，使其具有相似性。研究假设为，易激惹的哭声特征与可卡因的直接作用有关，而低沉的哭声特征与低出生体重继发的可卡因间接作用有关。结构方程模型（EQS）显示，可卡因对哭声有直接影响，表现为持续时间更长、基频更高、第一共振峰频率更高且变化更大。低出生体重继发的可卡因间接作用导致哭声潜伏期更长、发声次数更少、振幅更低以及更多发声障碍。与未暴露的对照组相比，暴露于可卡因的婴儿出生体重更低、身长更短、头围更小。研究结果与以下观点一致：在暴露于可卡因的婴儿中可描述出两种神经行为综合征，即易激惹型和低沉型，且这两种综合征分别归因于直接神经毒性作用和宫内生长迟缓继发的间接作用。
