The idea of bringing people back from the dead by transplanting their brains into donor bodies may sound like science fiction.

But the bizarre vision could be a reality within three years, according to a controversial Italian surgeon.

Professor Sergio Canavero is famed for his plans to carry out the first human head transplant next year, and says that he will then focus on brain transplants.

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Professor Sergio Canavero is famed for his plans to carry out the first human head transplant next year, and says that he will then focus on brain transplants

WHAT CRITICS SAY Critics say Professor Canavero's plans are 'pure fantasy'. The Italian has been compared to the fictional gothic-horror character Dr Frankenstein and Arthur Caplan, the director of medical ethics at New York University's Langone Medical Centre, has described Dr Canavero as 'nuts'. On his head transplant plans, Dr Hunt Batjer, president elect of the American Association for Neurological Surgeons, told CNN: 'I would not wish this on anyone. I would not allow anyone to do it to me as there are a lot of things worse than death.' Advertisement

Professor Canavero is Director of the Turin Advanced Neuromodulation Group in Italy, and is aiming to carry out the world's first human head transplant next year.

In a new interview with Ooom magazine, he has outlined his next plan, which involves thawing frozen brains and inserting them into donor body.

While many experts are sceptical that complex organs like the brain can be thawed without damage, Professor Canavero believes the first frozen brain could soon be awoken.

He plans to awaken patients frozen by the Arizona-based Alcor Life Extension Foundation.

Professor Canavero told Ooom: 'We will try to bring the first of the company's patients back to life, not in 100 years.

While many experts are sceptical that complex organs like the brain can be thawed without damage, Professor Canavero believes the first frozen brain could soon be awoken

WHAT IS CRYOPRESERVATION? WHAT IS CRYOPRESERVATION? The deep freezing of a body to - 196C (-321F). Anti-freeze compounds are injected into the corpse to stop cells being damaged. The hope is that medical science will advance enough to bring the patient back to life. Two main US organisations carry out 'cryonics' – Alcor, in Arizona, and Cryonics Institute, Michigan. HOW IS IT MEANT TO WORK? The process can only take place once the body is legally dead. Ideally, it begins within two minutes of the heart stopping – and no more than 15. The body must be packed in ice and injected with chemicals to reduce blood clotting. At the cryonics facility, it is cooled to just above OC and the blood is replaced with a solution to preserve organs. The body is injected with another solution to stop ice crystals forming in organs and tissues, then cooled to - 130C. The final step is to place the body into a container which is lowered into a tank of liquid nitrogen at - 196C. WHAT'S THE CHANCE OF SUCCESS? Many experts say there is none. Organs such as the heart and kidneys have never been successfully frozen and thawed, so it is even less likely a whole body – and the brain – could be without irreversible damage. HOW MUCH DOES IT COST? Charges at the Cryonics Institute, start at around $35,000 (£28,000) to 'members' for whole-body cryopreservation. The girl was charged £37,000, which may include costs such as transportation. Rival group Alcor charges $200,000 (£161,000) for whole-body preservation. HOW LONG BEFORE PEOPLE CAN BE BROUGHT BACK TO LIFE? Cryonics organisations claim it could be decades or even centuries. However Medical experts say once cells are damaged during freezing and turned to 'mush' they cannot be converted back to living tissue, any more than you can turn a scrambled egg back into a raw egg. Advertisement

'As soon as the first human head transplant has taken place, i.e. no later than 2018, we will be able to attempt to reawaken the first frozen head.

'We are currently planning the world's first brain transplant, and I consider it realistic that we will be ready in three years at the latest.

'A brain transplant has many advantages. First, there is barely any immune reaction, which means the problem of rejection does not exist.

'The brain is, in a manner of speaking, a neutral organ. If you transplant a head with vessels, nerves, tendons and muscles, rejection can pose a massive problem. This is not the case with the brain.'

While he is optimistic about the plans, he did admit that there could be physical and psychological issues after putting a brain in a different body.

He said: 'What may be problematic, is that no aspect of your original external body remains the same.

'Your head is no longer there; your brain is transplanted into an entirely different skull.

'It creates a new situation that will certainly not be easy.'

Earlier this year, the High Court ruled that a teenage girl could be cryogenically preserved, and scientists expressed their concerns.

Martin Ingvar, a cognitive neuroscientist at Sweden's Karolinska Institute said the cryogenic process was bound to fail and accused its practitioners of charlatanism.

Valery Spiridonov, a Russian computer scientist volunteered to be the first head transplant patient

'When you look at the brain, with 100 billion cells and 10,000 links between these and other cells... there's no way in hell you can restore the function in that,' he said.

Professor Canavero is working with a team of doctors from the Harbin Medical Centre in China, led by Dr Xiaoping Ren.

While the team believes that the technology to carry out the world's first head transplant will be in place by the end of the year, they are still seeking a suitable donor body.

Valery Spiridonov, a Russian computer scientist volunteered to be the first head transplant patient.

Last year, Professor Canavero claimed scientists in China had performed a head transplant on a monkey where they connected up the blood supply between the head and the new body. They did not, however, reconnect the spinal cord and the animal was unable to regain movement

But he has been turned down by the researchers, who said the first trial is likely to be carried out on someone who is Chinese, because the chance of a Chinese donor body will be higher.

Last year, Professor Canavero claimed scientists in China had performed a head transplant on a monkey where they connected up the blood supply between the head and the new body.

They did not, however, reconnect the spinal cord and the animal was unable to regain movement.