Vol. 4, No. 4, 1998 Page 6&7 
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Vol. 4, No. 4, 1998 Page 6&7 |
In the 1980s, scientists raised concerns that thousands of babies exposed to cocaine in utero would grow up to be uneducable and uncontrollable. These fears proved to be exaggerated, giving way to the current perception that little if anything is wrong with children exposed before birth to cocaine. However, research suggests that this new view is overly optimistic.
According to a research review by Barry Kosofsky, studies indicate that a subset of children exposed to cocaine in utero exhibit language deficits and "subtle but profoundly important behavioral deficits" including impulsivity and attention problems. In general, he says, the more cocaine a mother uses, and the longer she uses the drug during pregnancy, the more profoundly her child is likely to be affected. He speculates that genetic factors also play a role in the degree of impairment suffered by cocaine-exposed children.
More than 45,000 children born each year in the United States have been exposed to cocaine before birth. While many of these children appear to suffer no obvious effects, Kosofsky says, "the subtle behaviors that may be compromised [by prenatal cocaine exposure] are important for socialization, educability, and the adaptive skills required for individuals to become enfranchised in schools, communities, and society."
Kosofsky and colleagues Aaron Wilkins and Kenneth Jones have studied the effects of prenatal cocaine exposure on mice, and report that mice exposed to cocaine showed "a persistent behavioral deficit" in a test of selective attention skills, "with greater prenatal cocaine exposure and increased prenatal malnutrition resulting in more significant behavioral impairments." Even when the researchers controlled for malnutrition (by comparing the cocaine-exposed offspring to offspring of non-drug-exposed but diet-restricted mice), cocaine exposure was linked to impaired performance on a task measuring selective attention. Heavily exposed mice also exhibited brain and body growth retardation.
The researchers say their findings are in agreement with data from clinical studies of cocaine-exposed children, which indicate that "the dose and duration of prenatal cocaine exposure have direct effects on offspring brain and body growth and on behavioral performance."
"Cocaine-induced alterations in neuro-development," Barry E. Kosofsky, Seminars in Speech and Language, Vol. 19, No. 2, 1998, pp. 109-121. Address: Barry Kosofsky, Laboratory of Molecular and Developmental Neuroscience, Massachusetts General Hospital-East, 149 13th Street, Charlestown, MA 02129.
"Transplacental cocaine exposure 2: Effects of cocaine dose and gestational timing," Aaron S. Wilkins, Kenneth Jones, and Barry E. Kosofsky, Neurotoxicology and Teratology, Vol. 20, No. 3, 1998, pp. 227-238. See address above.