Influence of ageing and genetics on cognitive function

The ageing world population adds urgency to studying the causes of mental deterioration with age. The Scottish Mental Surveys of 1932 and 1947 subjected 11-year-old children to a well-validated test of general intelligence. Almost 2,000 of these individuals have been tested in subsequent years — and genome-wide single nucleotide polymorphism data collected — to provide a unique data set of lifetime cognitive measures. The data suggest that genetic factors underlie the differences in intelligence stability across the human lifespan. Estimates of the genetic contributions to cognitive stability and change in this cohort imply that a search for the genetic causes of lifetime cognitive change is worthwhile.