Researchers at the University of Dundee are refining the system

Developers hope the system, which uses a live video stream, will increase the independence of sufferers and help them remain in their own homes for longer.

The system works by prompting patients with visual or audio cues when they are carrying out tasks like hand washing.

The device is currently being tested at a long term care facility in Toronto.

Dr Jesse Hoey, who helped to design the device, said it could help dementia sufferers remain independent at home for longer.

He said: "Of course, the bathroom is the one place where they really want some privacy, so we want to develop techniques to help them there.

"Hand washing is a very important problem in the development of technology for people with dementia.

"Often they want to stay in their own home as long as possible, but they can only do that with help."

The system, which is being developed in partnership with the University of Toronto, is in the process of being refined so that it can identify when a sufferer with dementia is getting worse and react accordingly.