New research suggests that the infant brain is even more impressionable than previously thought. Opening a new window into the mysterious realm of how infants respond to their surroundings, researchers have found that parental bickering appears to have a visible effect on babies’ brains – even when the little ones are sleeping.

So psychologists at the University of Oregon asked mothers to fill out a standard survey gauging how often tempers flare at home, and then examined the brain activity of their 6- to 12- month-old babies using functional MRI, a type of noninvasive imaging technology designed to detect blood flow in real time.
That blood flow serves as a proxy for brain activity. Each of the 24 infants was placed in the laboratory scanner after a parent had put him or her to sleep. The babies wore headphones that delivered recordings of nonsense phrases read in neutral and angry voices- and that protected tiny ears from the machine’s loud banging noise.
The brain scans turned up an intriguing difference, says Alice Graham, the graduate student who conducted the study. Babies whose parents often fought at home had a stronger neurological response to angry tones-as shown by the intensity of the colors in a computer generated brain map-compared with babies from less conflict- ridden households.