23 July 2012
- Lost children: Charles Nelson’s most famous work follows the lives of orphans, like this young girl, at institutions in Romania.
Ten years had passed since the execution of Romanian dictator Nicolae Ceaușescu, and his infamous network of state-run orphanages was beginning to disintegrate. As these children came under international scrutiny, theMacArthur Foundation funded the Bucharest Early Intervention Project. Led by Nelson and several other scientists, the longitudinal study would randomly place some children in foster care and then compare their fates to those of children who stayed in the institutions.
Nelson’s team found that even when institutionalized children receive adequate food and decent living conditions, their social and physical neglect results in stunted growth, motor delays, anxiety, attention deficit, repetitive behaviors and low intelligence quotients1. But they also found an encouraging trend: Many of these symptoms can be at least partially reversed if the children enter foster homes before age 2.
From his lab at Boston Children’s Hospital, he is asking the same thing about autism: How do different risk factors — whether a single mutation, a family history or extreme social deprivation — lead to different manifestations of the diverse disorder?
| Good sport: Last year, compelled by a Facebook campaign to raise money for the nonprofit Autism Speaks, Nelson shaved his mustache of 30 years. |
Environmental effects:
In the late 1990s, Fox, Nelson and nine other researchers were part of the MacArthur Foundation’s Research Network on Early Experience and Brain Development. For nine years, the group met a few times a year to share ideas and launch pilot projects. One of these studies investigated the effects of maternal separation on rhesus macaque monkeys.
The results showed that it all comes down to timing: When 1-week-old monkeys are separated from their mothers, they tend to develop severe social deficits. If they are separated when they’re 1 month old, they wind up anxious and nervous, and if at 3 or 6 months, have no problems at all.
- Family ties: Nelson measures brain waves in young children — including his son, Colin, pictured here in 1986 at 6 months old.
Inspired, in 2000 the group launched the Bucharest study on the effects of foster care. The years since have seen growing international awareness about the dangers of institutional care, in large part because of the highly publicized scientific reports from the project. “When I travel to other countries, like Russia and China, they’re aware of the Bucharest study,” says Johnson, professor of pediatrics at the University of Minnesota. “There’s been a real change in attitudes.”
All of his work, Nelson says, suggests that the environment shapes the brain just as much as the genome does. And that has big implications for the autism field.
“The simplistic model that there is a genetic vulnerability, whatever that means, and some environmental hit, whatever that means, is probably the right one,” he says. “But so much attention has been paid to genetics, and too little to the environment.”
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