Memory problems may not be the first sign of Alzheimer’s.
Difficulty creating mental maps of new surroundings could be the earliest sign of Alzheimer’s, research finds.
The sign is present long before it is possible to clinically diagnose Alzheimer’s.
Dr Denise Head, one of the study’s authors, said:
“These findings suggest that navigational tasks designed to assess a cognitive mapping strategy could represent a powerful new tool for detecting the very earliest Alzheimer’s disease-related changes in cognition.
The spatial navigation task used in this study to assess cognitive map skills was more sensitive at detecting preclinical Alzheimer’s disease than the standard psychometric task of episodic memory.”
The study involved people trying to navigate a maze on a computer.
The maze had a series of different landmarks and wallpaper patterns to aid navigation.
People were tested on how well they could navigate a learned route and how well they created a mental map of the maze.
Dr Head explained the results:
“People with cerebrospinal markers for preclinical Alzheimer’s disease demonstrated significant difficulties only when they had to form a cognitive map of the environment — an allocentric, place-learning navigation process associated with hippocampal function.
This same preclinical Alzheimer’s disease group showed little or no impairment on route learning tasks — an egocentric navigation process more closely associated with caudate function.”
Study participants with preclinical Alzheimer’s also found it harder to learn the locations of objects in the maze.
Dr Head concluded:
“These findings suggest that navigational tasks designed to assess a cognitive mapping strategy could represent a powerful tool for detecting the very earliest Alzheimer’s disease-related changes in cognition.”
The study was published in the Journal of Alzheimer’s Disease (Allison et al., 2016).
