The next time you dig your partner in the ribs at 3 o'clock in the morning to tell him it's his turn to tend to your baby, remember this: it's not his fault he didn't hear the child's crying.
Well, that's his excuse, anyway – and now there is scientific proof!
For a new study has discovered that men's brains do not register a baby's cry – whereas women are hard-wired to be alert.
The National Institute of Child Health in the US asked 18 men and women (so not a huge study, we have to admit!) to let their minds wander.
During this time the scientists conducted brain scans. The researchers then played a recording of white noise interspersed with short clips of a baby crying.
The scans showed that while women immediately became more alert after hearing a baby's cry, the brains of men remained in a resting state.
"Determining whether these responses differ between men and women, by age, and by parental status, helps us understand instincts for caring for the very young," said study co-author Marc Bornstein.
Although brain activity patterns differed between men and women, there was no difference in the brain patterns between parents and non-parents. The researchers also played the cries of infants who were later diagnosed with autism.
Interestingly, the study found that both men and women reacted to autistic babies. Previous studies have shown that babies with the condition have higher-pitched cries. Hearing these cries interrupted the mind wandering of both men and women.