A study conducted by the University of Oregon has found a link between parents' arguing and affects on their sleeping infant's brains. The team of researchers lead by Alice Graham of the University scanned the brains of twenty sleeping babies (ages 6 months to one year) using magnetic resonance imaging and found that the infants brains responded significantly to angrier tones of the words spoken by adult males.
Researchers concluded that even moderate stress can alter the brain function of the extremely malleable infants' minds and noted, per an official statement released by Graham, that conflicts between parents can impact how infants grow up to handle stress and emotion. Additionally, the study found that even moderate stress can significantly impact an infant's overall development.
Researchers used nonsensical sentences spoken by male adults in a range of tones - from happy and neutral to mildly and very angry to measure the corresponding patterns of activity in the infants mind. They found that infants within "high conflict homes" per reports from their mothers had a much greater brain response to very angry voices. They noted that brain regions responsible for stress and emotion regulation throughout the roastral anterior cingulated cortex, the thalamus, the hypothalamus, and the caudate were more affected by the angry voice. This theory supports previous research conducted on animals which defined a link between early life stress and overall development and suggests that humans indeed experience the same.
The study will be published in full within an upcoming issue of the Psychological Science journal. And in the meantime, read more here