A test to identify long-term memory loss is likely to provide an early indication of Alzheimer’s disease and potentially help in reversing its effects by the development of new treatment, new research suggests.
Alzheimer’s disease is caused by proteins building up in the brain to form structures called plagues and tangles. This leads to the loss of connection between nerve cells and, eventually, to the death of the nerve cells and loss of brain tissue.
The findings showed that testing memory over a long timescale reveals early deficits in the brain’s ability to remember. These are not detected by checks for short-term forgetfulness, which is the current practice for diagnosis.
When short-term memory is used to diagnose Alzheimer’s disease – as is currently the case – it may not reveal the true extent of memory loss at the onset of the condition.
By testing long-term memory, it may be possible to detect the earliest signs of Alzheimer’s disease and offer interventions sooner.
A brain scan in combination with a memory test could identify early abnormalities in the brain activity of Alzheimer’s patients that would be otherwise undetected, the researchers said.
The researchers studied long-term memory in young mice, some of which had the equivalent of very early stage Alzheimer’s disease, and some of which were healthy.
Both groups were taught to locate a hidden platform in a pool filled with water, using signs on the wall of the room to navigate.
The results showed that when tested shortly after the initial task, both groups of mice were able to remember the way to their destination.
However, when both groups were tested one week later, the mice in the Alzheimer’s group had significantly more difficulty remembering the route.
Tests revealed that brain activity was normal in both groups of mice at their young age when no task was involved.
“We recognise that tests with animals must be interpreted with caution, but the use of these genetic models in conjunction with appropriate testing is pointing at an important dimension of early diagnosis,” said lead researcher Richard Morris, Professor at University of Edinburgh in Britain.
“It is widely acknowledged that earlier intervention is needed to effectively treat Alzheimer’s disease, and better diagnostic tools are needed for that. We believe that our approach could make a significant contribution,” added Vassilios Beglopoulos from University of Edinburgh.