Researchers are uncovering deeper insights into how the human brain ages and what factors may be tied to healthier cognitive aging, including exercising, avoiding tobacco, speaking a second language or even playing a musical instrument.Video above: How traffic pollution and brain function are relatedSome aspects of cognitive abilities in older age may be connected to test scores around age 11, according to a review paper published Thursday in the journal Genomic Psychiatry from Genomic Press New York.The paper, based on data from the Lothian Birth Cohorts studies in Scotland, suggests that about half of the variabilities in people’s cognition at older ages – why some people may have greater cognitive decline than others – may already have been present in their childhoods.Yet some adult lifestyle factors still appeared to be linked with improved cognitive performance and slower aging of the brain.”We have found that things like keeping physically and mentally …