Prenatal cocaine exposure may have lasting effects on a child’s ability to pay attention during the early school years, new study findings suggest.
“This study provides further evidence of a subtle but consistent effect on attention through early school-aged years,” lead author Veronica Accornero of the University of Miami commented in a statement.
Previous studies in animals have shown that cocaine exposure before birth leads to problems with selective and sustained attention. In some cases, the cocaine-associated deficits were apparent even in adulthood.
In humans, cocaine exposure has been linked to arousal and attention problems among infants and toddlers. Few researchers have examined whether such effects are long-lasting, however.
To investigate, Accornero and her colleagues looked at attention and response inhibition test results from 415 children involved in the long-term Miami Prenatal Cocaine Study. About half - 219 children were exposed to cocaine before birth and 196 children had not experienced such prenatal cocaine exposure. All of the children completed at least one Continuous Performance Test, which measures vigilance and response inhibition.
At the age of 5, the children were told to press a switch to identify a target figure out of two figures randomly presented on a computer screen. At the age of 7, they were presented with various bold-faced letters during a certain time period and were told to press the space bar for every letter except the letter X.
Children exposed to cocaine in utero had more errors in omission at ages 5 and 7 during their respective tests, the researchers report in this month’s Journal of Developmental & Behavioral Pediatrics.
The 7-year-old exposed children also took longer to press the space bar than did their non-cocaine-exposed peers, and were less consistent in their responses than were their peers, the report indicates.
These findings suggest that the cocaine-related deficits in attention processing “are generally persistent across the years bridging the preschool and school-age period,” the researchers write.
Despite the greater attention problems observed among the cocaine-exposed children, however, the “clinical significance is as yet unclear,” particularly with regard to these children’s school performance in later years, Accornero and her team note.
“Certainly, attention and the ability to maintain attention is an important skill that supports the development of other skills like language and behavior,” she said. “It’s possible that because of subtle deficits we may see an effect on academic performance. We just don’t know yet.”