A top doctor has suggested that many babies thought to have suffered from "shaken baby syndrome" may actually have been injured accidentally.

Leading neuropathologist David Doyle, of Southern General Hospital in Glasgow, has indicated that it takes much less force than most doctors believe to damage babies' delicate nerves in the neck which control breathing and can lead to swelling of the brain.

His study of 53 infants suspected of being victims of assault has suggested that the damage could have been caused by accidentally. The implication is that relatively mild manhandling could lead indirectly to fatal brain damage.

The research could undermine a number of convictions for the deaths of babies.

His study, published last week in New Scientist claims some doctors many be over zealous in ascribing brain injuries in babies to being shaken violently by their parents.

But a report in the Glasgow Herald last week challenged the findings. Dr Robert Minns, a consultant paediatric neurologist at the Royal Hospital for Sick Children in Edinburgh, told the paper it was unlikely the kind of injury associated with shaken baby syndrome could be caused by normal handling or play.

However, he added: "It can occur when people give in to exasperation and give the baby a shake without intending to cause injury.

"The truly non-accidental cases tend to have other injuries apart from these changes inside the skull, maybe older injuries, or a knowledge of previous abuse."