Current tests involve the patient memorising lists of words or other information to check their episodic memory. But the latest study shows that focusing on another group of mental abilities, visuospatial skills, flags up problems earlier. American researchers examined the time it took for symptoms to appear after a drop in brain function.
Tests on episodic memory revealed problems a year before, but join the dots and other tests of visuospatial skills highlighted changes three years before. Alzheimer’s is incurable, but drugs can slow its progress if the disease is caught early enough.