Why crying babies are so hard to ignore: Study suggests the sound of a baby crying activates primitive parts of the brain involved in fight-or-flight responses

Ever wondered why it is so difficult to ignore the sound of a crying baby when you are trapped aboard a train or aeroplane? Scientists have found that our brains are hard-wired to respond strongly to the sound, making us more attentive and priming our bodies to help whenever we hear it – even if we’re not the baby’s parents.

"The sound of a baby cry captures your attention in a way that few other sounds in the environment generally do," said Katie Young of the University of Oxford, who led the study looking at how the brain processes a baby’s cries.

She scanned the brains of 28 people while they listened to the sound of babies and adults crying and sounds of animal distress including cats meowing and dogs whining.

Using a very fast scanning technique, called magnetoencephalography, Young found an early burst of activity in the brain in response to the sound of a baby cry, followed by an intense reaction after about 100 milliseconds. The reaction to other sounds was not as intense. “This was primarily in two regions of the brain,” said Young. “One is the middle temporal gyrus, an area previously implicated in emotional processing and speech; the other area is the orbitofrontal cortex, an area well-known for its role in reward and emotion processing.”

Young and her colleague, Christine Parsons, presented their findings this week at the annual meeting of the Society for Neuroscience in New Orleans.