The amount of time children spend in institutional（学会的，制度的） care may affect how their brains develop. That's the conclusion of a new study carried out by researchers at the University of Wisconsin, Harvard Medical School/Children's Hospital Boston, and the University of Minnesota. The study is published in Child Development in the journal's January/February 2010 issue.

To learn how the deprivation（剥夺，损失） and neglect that institutionalized（体制化，制度化） children often experience affect brain development, the researchers looked at 132 8- and 9-year-olds. Some of the children were adopted into U.S. homes after spending at least a year and three-quarters of their lives in institutions in Asia, Latin America, Russia and Eastern Europe, and Africa. Others were adopted by the time they were 8 months old into U.S. homes from foster care（看护，照顾） in Asia and Latin America; most of these children had spent no time in institutional care, while some had spent a month or two in institutions prior to foster placement. On average, the internationally adopted children had been living with their families for more than 6 years. These children were compared to a group of American children raised in their birth families.

Children adopted early from foster care didn't differ from children who were raised in their birth families in the United States. Children adopted from institutional care performed worse than those raised in families on tests measuring visual memory and attention, learning visual information, and impulse control. Yet these children performed at developmentally appropriate levels on tests involving sequencing and planning.

The take-home message: Children make tremendous advances in cognitive（认知的，认识的） functioning once they reach their adoptive families, but the impact of early deprivation on their brains' development is difficult to reverse（颠倒，倒转） completely.

"We identified basic learning processes that are affected by early institutionalization," notes Seth Pollak, professor of psychology（心理学） and pediatrics（小儿科） at the University of Wisconsin, who was the study's lead author. "Policies that speed the time in which children can be removed from institutionalized care so they can develop within family contexts should be implemented（执行，实施） to decrease the likelihood（可能性） of learning problems later in children's lives."