A new study reveals that human brains have been getting larger over recent decades. Specifically, people born in the 1970s were found to have brain volumes 6.6% larger and brain surface areas almost 15% larger than those born in the 1930s. This increase in brain size, the researchers suggest, could be boosting our brain reserve, potentially lowering the risk of age-related dementias. The findings have been published inJAMA Neurology. The overall health of Americans has significantly improved over the past century, despite persisting health disparities. With people living longer, there’s a grow…