Last week brain developed a highly dopaminergic pathway regarding neurodegenration (read: 'Last week I found a very good reason to take a serious interest in dementia'). Only 2% of people aged 65-75 suffer dementia, but as the babyboomer generation gets older and medical science continues to develop cures for everything BUT neurodegeneration, diseases like Alzheimer's (50% of dementias) and vascular dementia (30%) will become some of the largest strains on European, north American, East Asian and Australian economies over the next few decades. Paying pensions will be difficult and the cost of physical and psychological care for boomers with dementia will outweigh TOTAL current spending on healthcare.
So. It turns out the best form of preventative treatment for neurodegenerative diseases is physical exercise. For details on this I strongly recommend a 35 min audio clip by John Medina called 'Brain Rule 1: Exercise', which is available on iTunes and explains in a clear, no-neuroscience-knowledge-needed way how increased blood and oxygen supply stimulates neurogenesis and helps fight the buildup of free radicals.
Very few people exercise properly, hence the obesity epidemic. Some of the aforementioned nations may therefore be open to alternative ways of avoiding disaster, say a brain implant that helps people exercise.. I'm sure you see where I'm going with this.
So, my apologies in advance to those of you who know a lot more than me about this subject - please correct me when I over-simplify and feel very free to point me to new sources of information, particularly audiovisual ones.