Medical science has found a link between an increased risk of dementia and those who live in the vicinity of heavy traffic or a major roadway. No firm explanation for how traffic increases one’s risk for developing dementia is given but the study was quite large (6.6 million involved) and numerous other risk factors accounted for too. But the takeaway message is that the closer that you live to a busy highway the greater your odds of developing dementia or some other neurological disability.