According to a study by Stanford University School of Medicine, a greater area of children’s brains is activated by their mother’s voice than by the voice of women they don’t know.
Brain regions in children that are strongly activated by the voice of their mothers extend beyond auditory ares to include regions involved in emotion, reward processing, social functions, detection of what is personally relevant and face recognition.
The study found that the strength of connections between the brain regions stimulated by the voice of the child’s mother would predict the child’s social communication abilities.
“Many of our social, language and emotional processes are learned by listening to our mom’s voice,” said lead author Daniel Abrams, PhD, instructor in psychiatry and behavioral sciences. “But surprisingly little is known about how the brain organizes itself around this very important sound source. We didn’t realize that a mother’s voice would have such quick access to so many different brain systems.”
Many years of research has revealed children prefer their mother’s voice. In one classic study, one year old babies sucked harder on their pacifiers once they heard their mother’s voice as opposed to the voice of other woman.
However, the mechanism behind this inclination was not known.
“We want to know: Is it just auditory and voice -selective areas that respond differently, or is it more broad in terms of engagement, emotional reactivity and detection of salient stimuli?”, said senior author Vinod Menon, PhD, professor of psychiatry and behavioral sciences.
This study tested 24 children aged between 7 to 12 with an IQ of at least 80. Children were all raised by their biological mothers and did not have any developmental disorders. Before the brain scans the voice of each mother was recorded saying three nonsense word.
Menon said these nonsense words were used to prevent the activation of a whole different set of circuitry in the brain.
The voice of two mothers whose children were not included in the experiment were recorded to use as controls.
The brain scans, revealed that even from very short clips, less than a second long, the children could distinguish their own mother’s voices with more than 97 percent accuracy.
“The extent of the regions that were engaged was really quite surprising”, said Menon.
“We know that hearing mother’s voice can be an important source of emotional comfort to children,” said Abrams. “Here, we’re showing the biological circuitry underlying that.”
Children whose brains showed a stronger degree of connection between all the different regions while hearing their mother’s voices had the strongest social communication ability.
This finding shows increased brain connectivity between the regions, is a neural fingerprint for increased social communication abilities in children.
Menon said this finding is an important template to examine social communication defects in children with disorders such as autism.
“Voice is one of the most important social communication cues, It’s exciting to see that the echo of one’s mother’s voice lives on in so many brain systems.”