Many an exhausted mum has suspected her husband of pretending to be asleep when baby cries in the middle of the night.
But the man really is firmly in the Land of Nod, say researchers.
While a baby’s sobbing is the number one sound most likely to wake up a woman, it doesn’t even figure in the male top ten.
Car alarms, howling wind and a buzzing fly are the prime noises guaranteed to disturb a man’s sleep.
The huge differences between the sexes were revealed by tests measuring subconscious brain activity.
They found that a woman’s maternal instincts kick in at the sound of a baby’s cries – whether or not she is actually a mother.
It was also discovered that women are more likely than men to find their sleep disturbed and men are more likely to be able to go back to sleep once they have been woken up.
The tests were carried out at the MindLab institution as part of research into the importance of a good night’s sleep.
MindLab recreated a ‘sleep environment’ for each volunteer before playing sounds and measuring the results on an EEG – electroencephalography – machine to measure how regular brain activity is disturbed by them.
Psychologist Dr David Lewis said: ‘There is nothing more likely to leave you feeling drained and depressed than disturbed sleep, especially when this happens over several nights.
‘As this unique study shows while some sounds, for instance your partner coughing or snoring beside you, disturb men and women equally, other noises such as a howling wind cause men to be more disturbed than women.
‘Women are more likely to be disturbed by a crying baby.
‘These differing sensitivities may represent evolutionary differences that make women sensitive to sounds associated with a potential threat to their children while men are more finely tuned to disturbances posing a possible threat to the whole family.’
The tests were commissioned by Lemsip Max All Night Cold & Flu Tablets. It found that 33 per cent of both sexes had moved to a spare room to get away from a partner’s snoring.
Other sounds which disturb both men and women include dripping taps, noisy drains and sirens from emergency vehicles.