The sound of a mother’s voice plays a critical role in a baby’s early development, multiple studies have shown. Now, researchers have demonstrated that the brain itself may rely on a mother’s voice and heartbeat to grow.

Researchers at Brigham and Women’s Hospital in Boston studied 40 babies born eight to 15 weeks prematurely. Like most severely premature babies, the infants were confined to incubators and spent limited time with their mothers.

“Preemies born this early are basically fetuses that happen to be out there by accident,” said Amir Lahav, an assistant professor of pediatrics at Harvard Medical School and senior author of the study.

Using tiny speakers placed inside the incubators, half the babies were exposed to the sounds of their mothers’ voices and heartbeats for three extra hours every day. The other half received no additional exposure to such sounds.

After 30 days, babies in the first group had developed a significantly larger auditory cortex — the hearing center of the brain — than those in the second group. The findings, published in Proceedings of the National Academy of Sciences, could help guide doctors and parents caring for premature babies, who often suffer from developmental and cognitive disabilities.

“This is part of the biological recipe for how you cook a baby,” Lahav said. “Any deviation from original recipe” could result in developmental problems, he added.


Another reason to drink coffee

Drink up, coffee lovers. Neurologists say a healthy appetite for coffee may reduce your risk of developing multiple sclerosis.

We’re not talking a cup or two of joe in the morning. Even a triple espresso might not be enough to register a difference.

In a new study, researchers found that Americans who downed at least four cups of coffee per day were one-third less likely to develop multiple sclerosis than their counterparts who drank no coffee at all. They also found that Swedish adults who guzzled at least six cups of coffee each day were also one-third less likely to get MS.

Put another way, people who eschewed coffee were 1.5 times more likely to be diagnosed with MS than people with a serious coffee habit.


Sleep may be clue to stroke risk

There’s no way to diagnose a stroke before it happens, but researchers say they’ve identified a clue to help doctors predict who’s at risk — the amount of sleep they get.

Older adults who said they slept more than eight hours were 46 percent more likely to suffer strokes in the next decade than adults who slept for six to eight hours, according to an analysis published in the journal Neurology.

Even worse, the stroke risk for people who went from sleeping less than six hours to sleeping more than eight hours was nearly four times greater than for people who consistently got six to eight hours of sleep.


Human DNA amps up mice brains

When injected with bits of human DNA, mice embryos grew brains that were 12 percent larger than those of embryos injected with the same genes from chimpanzees.

Scientists at Duke University, writing in the journal Current Biology, say the experiment demonstrates the role that a particular gene sequence, HARE5, plays in the development of the human brain, which is far heavier and more complex than the brains of our closest animal cousins. The research also may help reveal why humans suffer from such conditions as Alzheimer’s and autism, but chimpanzees do not.

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