Dr Helen Grant, a neuropathologist and former adviser to the International Olympic Committee on the risk of brain damage in boxing, dismissed claims by supporters of the sport that it was no more dangerous than rugby, football or horse racing.
'The object of the exercise is to knock your opponent out and in doing that you are inflicting a degree of brain damage,' she said. 'We have known this for many, many, years, and yet after each death the same arguments are trotted out.'
A study in the 1970s highlighted the danger of boxing relative to other sports, Dr Grant said. Neurosurgeons throughout the country were asked how many patients with post-traumatic brain damage they had treated. A list of their patients included 12 jockeys, 5 footballers, 2 rugby players, 2 wrestlers, 1 parachutist - and 290 boxers.
'When you consider the frequency of soccer or rugby matches relative to how many times a boxer fights, then the figures are alarming. And those injuries are accidental, while in boxing it is premeditated,' Dr Grant said.
However, Dr Adrian Whiteson, medical officer of the British Board of Boxing Control, said that since the 1940s there had been only 14 deaths worldwide from brain haemorrhage after a boxing injury. 'The brain behaves no differently whether it is a fist, a football or a shoulder (hitting the skull),' he said.
The brain has the consistency of cold custard and is vulnerable to injury because it is 'suspended' within the skull in a pool of fluid, attached only by a series of delicate bridging veins. It is free to move within the skull, 'swishing from side to side' after a blow, and moving against the skull lining which is irregular and sharp in some areas. Parts of the grey matter are shaved off, with the inferior frontal and inferior temporal areas, involved in memory and personality, at greatest risk.
Glancing blows to the head can damage an area known as the substantia nigra, causing symptoms similar to those of Parkinson's disease.
In a study of 15 brains removed from former boxers, 11 had Parkinsonian appearance.