By Shankar Vedantam
For years now, psychologists have been telling couples who yell at one another to stop for the sake of the kids. Such conflict in the home — even when no violence is involved — is associated with a host of negative and for children.
Some strands of have gone so far as to suggest that dissolving a marriage for kids than exposing them to high levels of conflict within a bad marriage.
Still, the effects of parental conflict do not appear to be experienced equally by all children. Some kids do badly when exposed to conflict; others seem to cope much better. Recently, researchers at the University of Oregon decided to try to get a handle on this variability: Is it possible, they asked, that experiences early in life might sculpt the brain in ways that shape the child’s response to conflict later in life?
Psychologists Alice Graham, Philip Fisher and Jennifer Pfeifer decided to take a look at what happens inside the brains of infants when they hear conflict and angry voices. The approach was straightforward: Use a noninvasive brain-scanning technique known as fMRI to scan the brains of infants and identify, in real time, which areas of the brain are activated by angry voices.
That is, unless, the psychologists reasoned, the infants were asleep. Was it possible that even during sleep, the brain continued to take in and process angry voices?
In a published in Psychological Science that is at least as remarkable for its methodology as for its results, the researchers had a couple of dozen infants brought into a brain-scanning lab at bedtime. First, the parents rocked the infants to sleep. Then Graham and her colleagues carefully placed the sleeping children inside the brain scanner. Via a pair of headphones, they piped in voices saying nonsense sentences such as, “I pulimented a mopar.” The voices spoke in different tones — angry, neutral and happy.
Graham, a doctoral student at the school, said the most surprising thing was not that the brains of infants responded differently to the different tones — which suggests that the brain is more than capable of taking in information while a child is asleep — but that there were stark differences among the children. Infants who came from homes with lots of conflict, where the parents yelled at one another and called each other unpleasant names, showed a heightened activation in certain areas of the brain.
“What we see for the infants in higher-conflict homes is that they are showing greater reactivity to the very angry tone of voice,” Graham says, “and that reactivity is in brain regions that we think are important later on in terms of your ability to regulate your emotions and function well.”