Karmel B Z, Gardner J M
New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA.
Dev Psychobiol. 1996 Jul;29(5):463-80. doi: 10.1002/(SICI)1098-2302(199607)29:5<463::AID-DEV5>3.0.CO;2-M.
The organization of arousal and attention as a function of intrauterine cocaine exposure was investigated in 180 normal nursery infants prior to hospital discharge and at 1 month of age. This was done by studying visual looking preferences when infants were in three arousal conditions: less aroused (after feeding); more aroused-endogenous (before feeding); and more aroused-exogenous (after feeding but including 8-Hz visual stimulation prior to each visual preference trial). The stimuli were light panels illuminated at three temporal frequencies between 1 and 8 Hz presented in pairs using a balanced presentation series of trials. Infants not exposed to cocaine demonstrated strong arousal-modulated attention, preferring faster frequencies when less aroused and slower frequencies when more aroused in both endogenous and exogenous conditions. In contrast, cocaine-exposed infants showed a lack of arousal-modulated attention and preferred faster frequencies of stimulation regardless of arousal condition. Similar differences in arousal-modulated attention as a function of cocaine exposure were obtained at 1 month after birth, indicating that these effects lasted longer than would be reasonable to attribute to the active presence of cocaine or its metabolites. This form of stimulus-seeking behavior was shown to be independent of confounding factors associated with prenatal cocaine exposure such as the absence of prenatal care, alcohol use, minority status, or gender, as well as mediating factors associated with growth such as birthweight. A direct and more chronic effect of intrauterine cocaine exposure on arousal-modulated attention and presumably on the developing CNS therefore was supported.
在180名正常新生儿出院前及1月龄时，研究了子宫内可卡因暴露对唤醒和注意力组织功能的影响。通过研究婴儿在三种唤醒状态下的视觉注视偏好来进行此项研究：唤醒程度较低（喂食后）；唤醒程度较高-内源性（喂食前）；以及唤醒程度较高-外源性（喂食后，但在每次视觉偏好试验前包括8赫兹视觉刺激）。刺激物是在1至8赫兹之间的三个时间频率下照亮的灯板，以平衡的试验呈现系列成对呈现。未暴露于可卡因的婴儿表现出强烈的唤醒调节注意力，在内源性和外源性条件下，唤醒程度较低时偏好较快频率，唤醒程度较高时偏好较慢频率。相比之下，暴露于可卡因的婴儿表现出缺乏唤醒调节注意力，无论唤醒状态如何，都偏好较快频率的刺激。在出生后1个月时，也获得了与可卡因暴露相关的唤醒调节注意力的类似差异，这表明这些影响持续的时间比将其归因于可卡因或其代谢物的活性存在更为合理的时间要长。这种形式的刺激寻求行为被证明与产前可卡因暴露相关的混杂因素无关，如缺乏产前护理、饮酒、少数族裔身份或性别，以及与生长相关的中介因素如出生体重。因此，支持了子宫内可卡因暴露对唤醒调节注意力以及可能对发育中的中枢神经系统产生直接且更持久的影响。
