Remember the child in your class no one ever wanted for their partner? Or that furtive-looking microbiologist in your hall of residence, who never spoke but ended up getting a first? Or your train-spotting ex-boss? You probably dismissed them, more or less sympathetically, as nerds and geeks. But what if the reason they struggled on the social fringes but succeeded academically was because they had the form of autism known as Asperger syndrome?
Asperger syndrome was unheard of 20 years ago. Now it seems to be everywhere. Ludwig Wittgenstein, the philosopher, who designed and made a sewing machine at the age of 10 and was friendless and teased by his fellow students, is thought to have had Asperger. So too is long-haired, green-slippered Albert Einstein, who used to lose his train of thought in the middle of giving a lecture.
Their modern day equivalent, Bill Gates, the Microsoft chief executive and Windows inventor, has been described as having autistic-type traits: lack of eye contact, poor social skills, a monotonous voice, a prodigious memory and a tendency to rock backwards and forwards during business meetings.
Twenty years ago we thought we knew what autistic people were like. They had low IQs and limited language, they behaved bizarrely, and they were put into special schools and residential homes. Autism occurred in about one in 10,000 of the population. Since then, it has been redefined as a spectrum ranging from mild to severe - and with that redefinition has come a massive increase in numbers. Some researchers say one schoolchild in every 70 is now diagnosed with a form of autism, including children with average or higher intelligence and no difficulty learning to speak. These are the ones categorised as having Asperger.
Much of this extraordinary increase is due to teachers and psychologists looking again at children who might have been written off as loners or anti-social, and recognising the typical autistic pattern of social reticence, poor imagination, inability to see into others' minds, emotional blankness, unusual obsessions. But unless something nasty has got into the water, the implication of finding all these extra autistic children is that there have always been large numbers of otherwise ordinary people with this cluster of symptoms, which means that an awful lot of us are walking around with AS and no idea that we have it.
Dr Simon Baron-Cohen, a Cambridge psychologist and autism expert, sees adults making this discovery all the time in his recently established clinic, the first in the country to specialise in late diagnosis of the syndrome. Their GPs have referred them because they fit a set of criteria suggesting that they have had unrecognised AS all their lives.
Some of them are terribly sad, says Baron-Cohen: "We are seeing people in their 20s, 30s and 40s. Many have awful stories to tell about being bullied at school, losing jobs, broken relationships. You see men who have meals and sex with their wives, but they don't have an emotional relationship. Their partners will start saying something that is a clear signal for emotional support, like "I got the results of my tests back from the doctor today" and they will say "Not now, I'm watching the football."
Since the clinic was established, Baron-Cohen has seen more than 50 adults and has a waiting list of another 20. To confirm Asperger, which is always detectable in early childhood, whereas schizophrenia or obsessive-compulsive disorder would appear in the teenage years, patients must, if possible, bring along a parent: "It can be a bit embarrassing, asking an 80-year-old mother if her 40-year-old son used to mix with the other children when he went to playgroup. But quite often you get a really clear picture. They say, 'My child has always been a loner; at school the only people my child talked to were the teachers'. That's a classic."
The majority of clinic attenders are men. (Nine out of ten autistics are male). Half are married or in steady relationships. Their jobs (most are in work) are largely in computing, scientific research, mathematics and engineering. They all have obsessions: "One 35-year-old woman had 2,000 videos and knew the directors of all of them," says Baron-Cohen. "You begin to get a picture of what these people's bedrooms are like."
But one man's obsession is another's life work. Many people with Asperger are high-achievers: one man reads dictionaries and speaks 10 languages; others are at the cutting edge of technology. Not all gain promotion to the level of their qualifications: one draughtsman had won a string of awards for his work, but remained low on the pay scale because he would not allow anyone who worked for him to stop for coffee or conversation.
Some work environments enable people with the syndrome to flourish. Richard Borcherds, professor of maths at Berkeley in California, was 38 and teaching at Cambridge when he won the Fields medal - the equivalent of the maths Nobel prize. He suspected he might have autism after reading an article about it when he was in his 30s and recognised many of its symptoms in himself. Borcherds, who describes himself as "socially inept", knew Baron-Cohen, who assessed him for a study of Asperger high-flyers and diagnosed that he did indeed have AS. Yet his career has certainly not suffered: "I've spent most of my life in universities, where eccentricity is fairly common, which probably made me stand out less. Most maths departments I've been in have at least one person who is clearly weirder than I am."
There are theories that whatever makes the Asperger brain function differently - and the current theory is that the right and left halves of the AS brain have insufficient "central coherence" or pulling-together power to see the overall picture - may also be of benefit in work which requires very precise attention to detail.
People may need to think like this, to a greater or lesser extent, to be the best computer analysts. That does not necessarily mean that all computer analysts have Asperger. But there are weird results from surveys of students and professionals in science and engineering showing that very large numbers - "sometimes more than one in four" - have a close relative with autism. Since autism has a powerful genetic factor, the implication is that the labs are full of people who fit somewhere on the autistic spectrum too.
But if they can live and work with Asperger, why go to the trouble of labelling them? Borcherds believes that for him, diagnosis was fairly pointless: "It might have been useful 20 or 30 years ago; maybe I could have had explicit lessons in social behaviour or something like that. But by now it seems to make little difference."
That is not what the people attending the Cambridge clinic feel, since they or their families - several patients have been sent along by their desperate wives - are by definition seeking some kind of help. Nor is it the view of Clare Sainsbury, daughter of Lord Sainsbury, the Labour peer and science minister, who was 20 and an Oxford philosophy student when she read about Asperger and recognised herself.
She grew up, she says, bullied, depressed, convinced that she was either schizophrenic or an abandoned alien from another planet. She trained herself to perform social smiles in front of a mirror, and got away with parroting back greetings like "hello" and "goodbye" until the awful day when somebody wished her happy birthday.
"Being diagnosed was a huge relief. Finally to have a name for it, to be able to say, 'this is how Clare is and it's not that she's not trying hard enough or being deliberately difficult'. I have been able to stop tortur ing myself, and it has been wonderful for my family because parents often get blamed for their children's behaviour and it must have been very hard for them to defend the way I behaved, even if it didn't conform to other people's ideas of normal."
Viewed from the majority perspective, people who fail to make eye contact are shifty or sinister. Asperger adults are constantly tailed by shop security guards, even though their inflexible mental processes make it unthinkable that they would break the law. Viewed from the perspective of an AS researcher at Yale University, the picture is rather different: "If we are autists, you guys are heterists. The diagnostic features of heterists are making lots of eye contact and overlooking details such as small coins on patterned carpets or car number plates."
Maybe what we need is to value as well as label the differences between the ways our different brains work. Or as Temple Grandin, an American autistic woman whose obsession with cattle pens led her to become the world's expert on humane corralling of cattle cattle, puts it: "What would happen if you eliminated the autism gene from the gene pool? You would have a bunch of people standing around in a cave, chatting and socialising and not getting anything done."
• From the Cambridge Lifespan Asperger Syndrome Service, email sb205@cus.cam.ac.uk
