A new study has indicated that changes to a person's intelligence throughout their lifetime may be influenced by genetic factors.
Researchers from the Universities of Edinburgh, Aberdeen and Queensland took part in the study, which explored the genetic and environmental factors that influence cognitive change.
Professor Ian Deary of the University of Edinburgh’s Centre for Cognitive Ageing and Cognitive Epidemiology, who led the study, told The Journal: “There are big differences between people in how much they change in intelligence between childhood and old age. Our samples are a rare opportunity to find out why.”
The study, which began in the late 1990s, has revealed that up to 24 per cent of cognitive changes may be due to genetic factors.
The study offers a new insight into the nature of intelligence, as it was previously believed that any changes were the result of environmental factors rather than genes.
The results further suggest that in many cases it is the same genes that affect intelligence, despite factors such as age.
Researchers used data that was collected by standard cognitive testing in Scotland in 1932 and 1947. The majority of children born Scotland in 1921 and 1936 underwent the test, and around 2,000 of these were traced to take part in the study.
DNA analysis was then used to determine the genetic similarities in these people, who took a second intelligence test between the ages of 65 and 79.
Scientists believe that identifying these genetic factors could lead to a greater understanding of the relationship between a person’s knowledge and their problem solving abilities, or even a person’s achievement in life.
Professor Deary said: “We are also looking at how genetic differences are associated with people's differences in brain structure (based on detailed MRI brain scans) and how this in turn affects thinking skills generally.”
The study is titled 'Genetic contributions to stability and change in intelligence from childhood to old age', and is available in the journal Nature.