General anesthetic drugs that physicians commonly administer to children undergoing surgery, when given to baby rats, trigger brain cells to commit a cellular form of suicide that leads to lasting memory and learning deficits, neuroscientists have found. So far, there's no evidence of similar effects in children who have received anesthesia, researchers say.
As the brain develops, countless nerve cells branch out and meet up. Excess neurons are then pruned back through a programmed process of cell death, called apoptosis, which yields precise networks. In rats, connections form most abundantly in the first 3 weeks of life, whereas in people the most prolific connection making begins during the third trimester of pregnancy and continues for 2 to 3 years after birth.
Researchers have known for years that exposure to alcohol during the brain's growth spurt can ramp up cell death in rats and people. In children whose mothers drink heavily during late pregnancy, this cellula