A wearable digital camera may hold the key to helping people who have memory problems, experts believe.
The camera can store up to 30,000 images
Sensecam, produced by Microsoft, takes photos of daily events every 30 seconds so they can be played back later at high-speed to jog memory.
Trials showed it helped people recall the event and emotions related to it.
Experts believe it could help people with general memory loss and more serious conditions such as Alzheimer's disease, but they say it is early days.
Universities in the US and UK are currently testing the device.
The camera, which can fit in the palm of a hand, can store up to 30,000 images - enough for a fortnight's use.
It has been tested on a 63-year-old woman with memory loss caused by a brain infection.
She spent about an hour every two days reviewing the images for a two-week period.
Without any other memory aids, she typically forgot everything within five days.
But during the test her memory steadily increased and after two weeks she could recall about 90% of the events she experienced.
Researchers are now testing the device on healthy elderly people who would typically struggle to recall memories as a result of ageing as well as patients with Alzheimer's.
Dr Chris Moulin, from Leeds University, who is involved in the research, said: "It is very early days, but the signs are encouraging.
"Not only were the memories of the event recalled, but the emotions surrounding it were.
"It has the potential to help people with conditions such as Alzheimer's and epilepsy as well as people who just struggle with general memory loss.
"And what is also particularly appealing is that there are no side effects."
Alzheimer's Society chief executive Neil Hunt said: "Many people with memory problems find aids such as diaries can offer psychological benefits.
"This new camera could potentially act in the same way although practically it needs to be very simple to operate and time would need to be set aside to select and store the images."