A social networking service for people with dementia will be launched today by a man who watched his grandmother slowly lose her memories.

Described as a Facebook for those who are struggling with dementia and memory loss, the website Ourbigbox.com is to be launched in Glasgow.

The free service is being launched by Scott Downie, a web designer who sold his business to develop the project.

Mr Downie already runs the charity Memory Box Network, which delivers workshops to help reconnect sufferers of Alzheimer's Disease and other forms of dementia with their grandchildren. It also holds workshops in schools.

The new project will allow family members, carers and friends to create a virtual memory box for someone who is struggling with the loss of meaningful communication and conversation.

Based on the concept of reminiscence therapy, which has found prominence in Scotland through the acclaimed Football Memories project, the social networking site is intended to help stimulate memories and help those suffering from dementia to feel more connected with other people.

Crucially, it will allow uploaded images, audio and video files to be shared, so that different family members can use places, events and faces from the past to help provoke discussion and memory.

People with dementia can be encouraged to talk about their early lives with the use of photographs and pieces of music or items that will be familiar from their past.

Personal images will be able to be as private as users wish, while others, such as photographs of a public place, like a park or school, can be shared so they might be used by others on the network who might also react to them.

Mr Downie says using a picture of a place where someone spent a lot of time could be more effective than a memorable trip or occasion.

In his grandmother's case, it was a bus stance in Sauchiehall Street, Glasgow, he says, where she had spent hours at a time. "If you spent a lot of time there, the likelihood is better that you recall a story related to a place," he said.

"Reminiscence therapy helps those with dementia know they are not being left behind. The website is a digital repository of memories that can be accessed and added to by family members and friends wherever they are in the world."

In the past, people might have to travel across Scotland to access libraries and archives for old photographs - and then find their relative did not respond to them, Mr Downie said. Using the network other people can flag up images that have been effective for their own relatives. The system can also suggest other content based on what users have been looking at.

The site was set up with funding of £80,000 from the Nominet Trust, which promotes imaginative use of social media. Mr Downie aims for it to be self-funding within three years.

The service will launch at the annual conference of Alzheimers Scotland. Chris Lynch, spokesman for the charity, said it had worked with Mr Downie to help develop Ourbigbox.com: "We already know reminiscence therapy works from the Football Memories project.

"Testing the service on tablets has shown that people with dementia very intuitively understand the tablet mechanism, even if they would normally be intimidated by computers.

"We are keen to encourage inter generational communication. This means people can also participate from a distance where families are geographically separated."