Brains that maintain healthy nerve connections as we age help keep us sharp in later life, new research funded by the charity Age UK has found.
Older people with robust brain 'wiring' that is, the nerve fibres that connect different, distant brain areas can process information quickly and that this makes them generally smarter, the study suggests.
According to the findings, joining distant parts of the brain together with better wiring improves mental performance, suggesting that intelligence is not found in a single part of the brain.
However a loss of condition of this wiring or 'white matter' the billions of nerve fibres that transmit signals around the brain can negatively affect our intelligence by altering these networks and slowing down our processing speed.
The research by the University of Edinburgh shows for the first time that the deterioration of white matter with age is likely to be a significant cause of age-related cognitive decline.
The research team used three different brain imaging techniques in compiling the results, including two that have never been used before in the study of intelligence.
These techniques measure the amount of water in brain tissue, indicate structural loss in the brain, and show how well the nerve fibres are insulated.
The researchers examined scans and results of thinking and reaction time tests from 420 people in the Lothian Birth Cohort of 1936, a group of nearly 1100 people whose intelligence & general health have been tracked since they were 11
The research was part of the Disconnected Mind Project, a large study of the causes of people's differences in cognitive ageing, led by Professor Ian Deary.
Study author Doctor Lars Penke said "Our results suggest a first plausible way how brain structure differences lead to higher intelligence. The results are exciting for our understanding of human intelligence differences at all ages
|Contact: David Scott|
University of Edinburgh