Kids' language gap begins even earlier
A landmark study nearly 20 years ago found that by age 3, the children of wealthier professionals have heard words millions more times than those of less-educated parents, giving them a distinct advantage in school and suggesting the need for increased investment in prekindergarten programs.
Now a follow-up study has found a language gap as early as age 18 months.
The new research by Anne Fernald, a psychologist at Stanford University, which was published in Developmental Science earlier this year, showed that at 18 months children from wealthier homes could identify pictures of simple words they knew — "dog" or "ball" — much faster than children from low-income families.
By age 2, the study found, affluent children had learned 30 percent more words in the intervening months than the children from low-income homes.
"That gap just gets bigger and bigger," said Kris Perry, executive director of the First Five Years Fund, an advocate of early education for low-income children. "That gap is very real and very hard to undo."
Study ties poverty to brain development
Children raised in poverty or in orphanages experience chronic stress that can have long-lasting effects on the brain, setting them up for mental and physical ailments as adults, two studies found.
The stress of poverty may affect regions in a child's brain that control emotion, according to research published Monday in the journal Proceedings of the National Academy of Sciences. A second study found that children who had lived in an orphanage were more anxious than those who hadn't.
In childhood, the brain is still immature and developing rapidly so it is more sensitive to high-stress situations than an adult brain, said Pilyoung Kim, lead study author of the childhood poverty study.
The findings from both papers suggest that early intervention programs to address chronic stress may benefit these children, the authors said.
"Long-term exposure to chronic stress is likely to cause wear and tear in children's physical and psychological systems for coping with stress over time," said Kim, an assistant professor and director of the Family and Child Neuroscience Lab at the University of Denver. "Living in poverty at a young age can cause long-lasting changes in brain development."
Why don't sugar, honey and molasses ever rot?
"It's almost all about water," said Kathie T. Hodge, associate professor of mycology at Cornell University.
Molds and bacteria cannot survive on very sugary foods, she said, because the concentrated sugar, like salt, has the effect of drawing moisture out of cells.
"We talk about a food's water activity, how much of its water is available," Hodge said. "Sugar, honey, molasses and maple syrup have very low water activity. In fact, they will pull water right out of the air."
That's why maple syrup left on the table will absorb water from a steamy kitchen and eventually become dilute enough to support mold growth, Hodge said.