An Australian trial study has shown how specially trained dogs can help younger people suffering from dementia as their world becomes increasingly confusing.
The study followed about 15 dogs and their owners for three years, and the results are yet to be written up.
The animals, which have not quite passed muster in guide dog training, are being used as companions for people with dementia in their 40s and 50s.
University of Melbourne professor Keith McVilly said the dogs were already improving the lives of not only the people taking part in the trial, but also their families.
He told Nine to Noon people with dementia could become increasingly anxious as they found it harder to make sense of what was happening around them
"And it's having the dog there as an influence of calm, it's ... a psychological anchor to keep them feeling safe."
Prof McVilly said the animals helped people to not get lost in their homes, such as on the way to and from the bathroom in the middle of the night.
The dogs not only provided practical assistance to their owners, but became "part of the family unit" and were calming for other members of the family - even giving them respite from the demands of care.
"With the dog there we're finding that carers are more happy to leave their loved one at home for short periods so they can get out and about and do things," he said.
"And they're also much happier that their loved one is going down the street to the shop in the company of the dog which provides that little extra reassurance."
Prof McVilly said the dogs have different personalities from guide dogs, which makes them perfect for working with younger people suffering from dementia.
"They're ... more [like] companions, more nurturing, rather than leading [the person]."
"But their temperament, their intelligence and their ability to be trained makes them absolute wonders at being assistance dogs."
Prof McVilly said humans and dogs have been living together for more than 15,000 years, but the therapeutic benefit of the relationship was only beginning to be explored.
Other people who could be helped by assistance dogs include young people with autism, he said.
Dogs could also be used to spot the warning signs of someone about to have an epileptic seizure or a diabetic fit, Prof McVilly said.