It was genuinely unplanned, but in one of life's spooky coincidences, the Dana Centre launched Enhancing Me last month, a book about the science of human enhancement, just as the new series of Heroes was hitting our screens. If you haven't discovered it yet, Heroes is a sci-fi TV serial (Thursdays, BBC Two, 9pm) in which ordinary mortals have each developed a specific superhuman power. Commanding electricity, flying, walking through solid walls, regenerating - it's familiar X-Men territory. But is it science fiction or can humans enhance their powers, both physical and mental?

Most headline writers are convinced that super-enhancing bionics are already with us. Earlier this month, two blind people had devices implanted in their eyes which received pictures from a camera mounted on a pair of glasses. It allowed them to distinguish shapes and light and shade.

This is an extraordinary achievement but it's hardly the 20:20 vision enjoyed by LaForge with his special visor in Star Trek, let alone being able to read a car numberplate from three miles away like the Six Million Dollar Man. On the other hand, people do already have access to cochlear implants, that restore high-quality sound to the previously deaf. But is this enhancement? “No,” says Dr Pete Moore, author of Enhancing Me. “It's human beings using clever tools.” He distinguishes between per-sonal enhancement, which might be as simple as someone using a walking stick, and human enhancement, which would push humans beyond the bounds of what we can now achieve: running 100m in five seconds,for instance.

The carbon-fibre cheetah feet of “Blade Runner” Oscar Pistorius enable him to compete with top-class athletes, but have they enhanced his personal speeds? Since he lost both legs in childhood, a before and after comparison is not possible. But what seems clear, after investigations by officials who banned him from competing in the next Olympics, is that Pistorius does use 25 per cent less energy when running, so perhaps you could say that he definitely is enhanced, if not in speed, then in how his body behaves when he runs.

Transhumanists are people who believe it is both desirable and possible to extend human capabilities through technology. Todd Huffman is an American neuroscientist and transhumanist who has had a weak magnet inserted beneath the skin of his ring finger. He also has a permanent screw fixing in his skull so that he can attach decorations such as chrome horns at will. Through his finger he is able to detect weak magnetic fields such as security detection systems in shops and sense things that others miss. For instance, his finger buzzes if an electric socket is live and he can sense whether software on his laptop is running efficiently. This is genuinely more likely enhancement. Curiously, “communicating” with electrical appliances is one of the powers possessed by a character in Heroes.

The man who calls himself Cyborg 1.0

Kevin Warwick is a professor of cybernetics at Reading University. He has dubbed himself Cyborg 1.0, the first in what he thinks will be increasingly advanced human technology amalgams. His first experiment involved inserting a device into his arm that allowed him to open doors, in the same way that cats fitted with special collars can open cat flaps. Would you call him a cyborg if he had the same device, but merely stashed in a pocket?

However, a subsequent implant in 2002 is more interesting. It plugged directly into the nerves in his arm. One experiment involved putting ultrasonic sensors (of the sort used in top-end cars for parking) on either side of a baseball hat, linking them to his implant. As the sensors approached an object, they sent a buzzing signal to his nerves.

Within six weeks he could move around blindfolded. A simpler electrode was put into his wife's arm in an effort to enhance communication between them. He was also able to connect his nerves up to a computer in Columbia University, New York, networking them back to a robotic system in his lab. He claims that: “My body was, in effect, extended over the internet.”

But half-human, half-machine as we might expect of a cyborg? It's a million miles away.

A more likely enhancement relates to mood. Could we have a happiness switch built in? Tipu Aziz is the Oxford neurosurgeon best known for his work with movement disorders, such as Parkinson's disease. He implants an electrode in a specific part of the brain. When this area is electrically stimulated, the patient's tremor stops instantly. Many thousands of people now have these implants for controlling Parkinson's and they are now also being used to control pain and, significantly, depression and other mood disorders. What if they were available for people who were not depressed but wanted to feel in a party mood or experience more intense levels of happiness?

Aziz believes this is possible, provided, of course, that people were prepared to risk brain surgery to have the electrode implanted. But given the example of Warwick and Huffman, there are certainly people out there who would be prepared to do this.

There are less drastic routes to becoming temporarily enhanced. We know that caffeine, for instance, boosts concentration, and drugs such as Modafinil, devised for people with narcolepsy, enhance alertness. Medicines used for therapy by those with Alzheimer's and attention deficit hyperactivity disorder (ADHD) can also be used by those with normally functioning minds to enhance their brain activity.

But while a drug like Ritalin can improve concentration in those with ADHD, those without the condition report a “tunnel effect”. It aids attention but at the expense of creativity and imagination, nor is the effect long-lasting.

Another possible route to enhancement might be through gene therapy. This week we have already seen reports of sight restored by this therapy, but the technique could conceivably also be used to create enhanced humans. For instance, Repoxygen is a gene therapy developed by Oxford Biomedica to treat anaemia. It persuades the body to produce more erythropoietin, a hormone that increases the number of red blood cells. If this were used by athletes, they would have greater levels of endurance and stamina. Other forms might be used to increase muscle mass. But these techniques (which are as yet confined to lab mice) would likely only slightly improve the already gifted sportsman, not transform the likes of you and me from Sunday cyclist to Tour de France winner.

Ethical concerns

There are many ethical concerns about enhancement. Most are about fairness, particularly in relation to competitive sport or exams. But there are darker worries. If a brain implant was shown to control mood, could you force a violent criminal to have one? If many had mood-enhancing implants, could someone override their individual controls and thus control them all? And there are always two sides to the many coins in the enhancement debate. For instance, chemicals called ampakines can enhance memory, but some would rather take drugs that prevent rather than enhance memory formation, such as those who work in stressful situations or those who have been subjected to trauma. What if soldiers were forced to take such drugs?

There is also an issue about diversity. Ask deaf people whether they want a cochlear implant and some, as Heather Bradshaw, a researcher who is working on a thesis on enhancement and disability at the University of Bristol has done, will say no. “They would rather build on some quality or talent that they already have,” she says.

It seems one man's enhancement is another man's burden.

Enhancing Me, by Dr Pete Moore (John Wylie, £12.99), is available from Times BooksFirst for £11.69, p&p free: 0870 1608080 or visit timesonline.co.uk/booksfirst

SUPERHUMANS IN NUMBERS

4,963 the number of World Transhumanist Association members

10kg the weight that the i-Limb, a bionic arm developed by Scottish scientists, can lift above head height

50% the amount of muscle growth in mice when injected with DNA

120 years the predicted average human life-span by the year 3000

Source: Times database

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