The research team in the Neuropsychopharmacology Laboratory at Yale School of Medicine found that prenatal exposure to cocaine leads to over-stimulation of the medical prefrontal cortex of the brain in the offspring, and a dramatic impairment in learning.
"Children exposed to cocaine in the womb may have a problem with excitable neurons in part of the brain that helps control attention and memory," said Bret Morrow, associate research scientist, associate clinical professor and lead author of both studies. "Potentially, this excitable prefrontal cortex may be the basis of the learning deficits in these children."
"The use of cocaine among women of childbearing age is alarmingly high," he added. "When a pregnant woman uses cocaine she also exposes her fetus to the drug. Studies have shown that these cocaine exposed children have increased occurrence of symptoms similar to those seen with attention deficit hyperactivity disorder increased distractibility, impulsivity and select learning deficits. Based on our animal studies, we are concerned the effects could very well be lifelong in humans."
The first study published in the February issue of Behavioral Brain Research involved administering cocaine to pregnant rats and then assessing short term memory in the offspring when they were adolescents and adults.
The test animals were placed in a cage with two identical objects. They were then removed from the cage for a brief interval, and then put back in with one of the former objects and a second new object. If the animal explored the new object preferentially, that was taken as evidence that the animal remembered the first object. The test is similar to one
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