Memory problems might not always be the first sign of dementia. Researchers from the University of Kansas studied 444 people, of whom 134 developed dementia. They gave the participants in the study a series of different cognitive tests then looked back to see which of them developed dementia. They found that visuospatial skills - like the ones people use to read a map or put together a jigsaw - began to decline sharply three years before diagnosis and an overall decline in mental abilities was seen the following year. However, a sharp decline in memory skills was not seen until one year before a diagnosis of Alzheimer's.
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