The sound of babies crying is uniquely able to get adults to react at speed, British scientists said on Tuesday.
A study by Oxford University researchers using the classic arcade game "whack-a-mole" found that adults' responses were swifter when they were listening to babies crying, compared to hearing sounds of adults in distress or twittering birds.
"The improvements in speed and dexterity may reflect an evolved response that kicks in when an immediate reaction to a baby in distress is required. It is not hard to see how this could facilitate care-giving behavior," said Morten Kringelbach of Oxford's psychiatry department, who led the study.
The research team compared the scores of 40 volunteers playing 'whack-a-mole' - which requires players to hit one of nine as they light up at random - after listening to various cries including babies crying, adults in distress and birdsong played at a similar pitch to the infants' cries.
The results, published in the journal Acta Paediatrica, suggest baby cries get special attention, Kringelbach said.
"Few sounds provoke a visceral reaction quite like the cry of a baby," he said in a statement. "For example, it's almost impossible to ignore crying babies on planes...despite all the other noises and distractions around."
The scientists said their work was not purely an academic exercise, but could help researchers studying women with post-natal depression, who may be suffering some kind of disruption to this baby cry response.
"Depression and postnatal depression may result in some people not attending so much to babies' cries. We are looking at whether interventions can make a difference to this," Kringelbach said.