The nine-year-old, of Watson, has autism and prefers a strict routine and his own company; people are too complicated for friendships.

But now a dachshund called Major is starting to enter his world.

The Gurney family bought Major from the pound in October for Max, and mother Rachel said she had already seen big changes in her son.

''He's very attached to him already,'' Mrs Gurney said.

''People talk to animals with affection. Most people will see an animal and give them a nice greeting, and what that does is it shows children with autism how to greet and how to interact.

''I think the dog has really got a sixth sense. He just knows what Max is about.''

A new study at Monash University in Melbourne will explore how man's best friend may change the world of a child with autism.

There is a growing number of organisations worldwide training dogs to assist children with autism. Many have been inspired by Nuala Gardner's book, A Friend Like Henry, which tells the story of how Gardner's son, Dale, conquered autism with help from a golden retriever.

School of psychology senior lecturer Pauleen Bennett said academics wanted to scientifically evaluate the extraordinary claims of the benefits of dogs for children with autism. ''It's about trying to bring science into something that a whole lot of people think is a really good idea,'' Dr Bennett said.

''Dogs are really special. They have a different relationship with people than other animals do.''

The $40,000 study will take place over the next three years. Researchers will work with Bendigo-based Righteous Pups Australia, a non-profit organisation, which trains assistance dogs for people with disabilities. The organisation is the only one of its kind in Australia to train assistance dogs for children with autism.

It trains these dogs, predominantly Labradors, in companionship and behaving appropriately in public spaces. It also teaches the dogs to interrupt repetitive behaviour by gently nuzzling or using their paw to distract a child. Righteous Pups began training assistance dogs for children with autism in 2005 and has trained and established nine dogs with families across Australia.