Sir Paul McCartney's claim that he can remember being born may be extraordinary, but scientists say it is almost certainly impossible.

The Beatles legend recently revealed that he remembers hearing forceps clanging during his own delivery and even recalled the doctor's unusual hairstyle.

However, memory researchers say the human brain is simply not equipped to store autobiographical memories from birth.

The phenomenon is known as ‘infantile amnesia’, a well-established quirk of memory that leaves most adults unable to recall events from their first few years of life.

Experts say that adults rarely remember events that occurred before the age of three and often have only patchy recollections of experiences between the ages of three and seven.

Psychologist Vanessa LoBue, from Rutgers University, explained: ‘What we do know is that any memories we claim to recall before the ages of two or three might have been constructed by someone else’s retelling of an event.

‘No one can really remember anything before they were around that age.’

Experts have explained that infantile amnesia does not mean that babies are incapable of forming memories.

In fact, infants can recognise their mother's face within hours of birth and are capable of learning and remembering information.

The problem is that these early memories are not stored in the same way as the autobiographical memories we rely on later in life.

Scientists believe the rapidly developing brain effectively wipes the slate clean as it grows, making those earliest experiences impossible to consciously retrieve.

Dr Kaori Ikeda, science policy officer at the Australian Brain Alliance, explained that the brain is still developing after birth and that memory systems continue to change throughout childhood.

‘At birth, a human baby’s brain is only a quarter of its adult size,’ she said. ‘By the age of two, it’ll be three-quarters of the size of an adult brain.

‘This change in size correlates with the growth of neurons and the testing and pruning of connections.

‘Scientists think that this rapid rate of neuron production in childhood could contribute to our higher rate of forgetting when we’re young. How? By forming new connections with memory circuits, the masses of new neurons may disrupt existing networks of already-formed memories.’

Neuroscientist Flavio Donato, from the University of Basel, explained there is a ‘paradox’ when it comes to brain growth and memory.

‘In the moment that the brain is learning at a rate it will never show again during the whole lifetime, those memories seem not to stick in the brain,’ he told Science.

Scientists also point out that autobiographical memories rely on an understanding of time, place and the self, concepts that babies have yet to develop.

So while Sir Paul may genuinely believe he remembers the moment he entered the world, scientists say the far more likely explanation is that his brain has woven together fragments of stories, family memories and imagination into a scene that feels real.