How did a world expert in autism miss a diagnosis right under his nose?

That's the question that Professor Tony Attwood still mulls over and deeply regrets.

The clinical psychologist is recognised as a leading authority in the diagnosis and management of Asperger's syndrome.

But all his skills and research couldn't help his son Will.

It was only when the 35-year-old ended up with an overwhelming drug addiction and in jail for burglary that Professor Attwood had a sudden insight.

While watching family videos of himself and Will as a four-year-old, Professor Attwood noticed an inability to connect with him.

"I was trying to interact with him, but even at the age of four, there was a barrier," Professor Attwood said.

"[My daughter] Rosie is a teacher of kids with autism and we just turned to each other and said, 'He's Asperger's'!"

Will Attwood was not diagnosed with Asperger's syndrome until he was an adult. ( Australian Story: Anthony Sines )

Many have since wondered how a world expert on Asperger's could overlook a diagnosis so close to home.

But as Professor Attwood points out, the condition hadn't even been given a name back in Will's childhood.

He fell into the same trap that has plagued parents for years.

"We just thought he was a naughty, ADHD, difficult, emotional kid."

Autism a gift not something to be 'fixed'

Professor Attwood runs his clinic from underneath his house on the outskirts of Brisbane. Such is the demand for his skills, his waiting list is fully booked well into the future.

He's been researching autism for nearly four decades and is credited with writing "the bible" on Asperger's syndrome.

Asperger's, also known as high-functioning autism, is where the brain is wired differently in terms of perceiving, thinking, learning, and relating to the world.

Having grown up with a stepfather who was on the spectrum, Professor Attwood said he learnt to speak the language of those with Asperger's syndrome — or "Aspies" as they call themselves.

"I describe myself as a translator between two different cultures — to explain the neurotypical world to the Aspie and the Aspie world to neurotypical," he said.

Famous 'Aspies' Albert Einstein

Albert Einstein Peter Sellars

Peter Sellars Vincent Van Gogh

Vincent Van Gogh Andy Warhol

Andy Warhol Lewis Carroll

Lewis Carroll Marie Curie

Marie Curie Courtney Love

The University of Queensland adjunct professor is credited with revolutionising the approach to Asperger's syndrome.

Clinical colleague, Dr Michelle Garnett, says he was the first psychologist in the world to see Asperger's syndrome as a gift and not as something to be "fixed".

"It's something to be congratulated for, something to be enjoyed in the person's life, and we always look for those gifts, those strengths and abilities that the person has because they're always there," Dr Garnett said.

Professor Attwood's patients say his skill lies in his ability to connect with them, find their special talent and harness it to help them to reach their potential and lead a fulfilling life.

He believes the intense focus on a special interest shown by people with Asperger's has led to some of the world's greatest achievements.

"I think many of the heroes in life, and the greatest scientists and artists, actually have Asperger's syndrome," Professor Attwood said.

'I don't hold it against him'

It's with deep sadness that Professor Attwood reflects on his inability to help Will find that special talent when he was a child.

"In hindsight, there are things that I'd have liked to have focussed more on in terms of helping him cope with his intense emotions, but sometimes, as a parent, it's hard to be objective in that situation," he said.

Will's mother, Sarah Attwood, believes the sort of early intervention programs that her husband now recommends for his patients would have helped Will.

"Nowadays, we would have taught him how to manage his frustration … to sort of self-soothe and stay calm," Ms Attwood said.

"He may even have avoided the drug path, who knows, we'll never know."

Will Attwood doesn't hold his father responsible

"I don't hold it against him in any way, shape or form for failing to diagnose me," Mr Attwood said.

"It seems to me, for whatever reason, that my Asperger's was less pronounced when I was a child."

The chicken whisperer

Summer Farrelly, 10 and her mother Cynthia from Bundaberg, Queensland. ( Australian Story: Anthony Sines )

One of Professor Attwood's patients is 10-year old-Summer Farrelly.

He identified her ability to relate to chickens and has encouraged her passion.

But while chickens adore her, the pecking order in the playground is a real problem for her.

"Most kids think I'm weird because I'm not interested in fashion, music or technology," Summer said.

"I like chickens because they're non-judgmental, and they make me feel loved, needed and special."

Summer said she had a breakthrough when she met Professor Attwood.

"He understands my autism and he gives me tools to help with it, and he's kind of my go-to guy," she said.

Asperger's the 'next stage of evolution'?

With at least one in every 100 children being diagnosed on the spectrum, Professor Attwood wonders if Asperger's may be the next stage of evolution.

He believes the human race needs out-of-the box thinkers to solve the world's big problems.

"I think in the future some of our major problems, whether it be pollution, electricity or whatever, will be solved by people with Asperger's," he said.

"I think we need to embrace and encourage their particular abilities because our future is based on such individuals. And in a way, is Asperger's syndrome the next stage of human evolution?"

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