Brains Age Earlier Than We Thought

Scientists have thought that a measurable decline in brain function, such as speed of perception, spatial skills, or verbal function, begin around 5 years before death. But new research shows that acceleration in mental decline starts around 15 years before death. The scientists from Sweden published their findings in the journal Neurology.

In a study lasting 30 years, researchers tracked 288 men and women from age 70 until death; they were all free of dementia. During the study their mental skills were measured at regular intervals. Three functions were selected: perceptual speed (e.g. how quickly people can compare numbers), spatial ability (e.g. how to understand and analyze visual information from diagrams and pictures), and verbal skills (e.g. understanding a paragraph, recognizing synonyms and antonyms).

By charting the scores for these functions over time, the onset of ‘terminal decline’ was determined for each participant, and set in relation to the individual’s death. The onset of decline was found to precede death by the following number of years:

Verbal Skills - 6.6 years

Spatial Ability - 7.8 years

Perceptual Speed - 14.8 years

These periods are considerably longer than those reported 5 years ago, using similar methodology: 3.3, 6.0, and 2.75 years for semantic memory, visuospatial memory, and perceptual speed, respectively.

What are the reasons for such declines? Maybe lack of exercise and mental stimulation in old age, or increasing health problems. Further studies will clarify this. In the meantime, those of us over 70 must keep our brains exercised – we know that there are things we can do to postpone dementia, at any rate!