Sydney - A musical 40 years ago was her first success and Australian playwright Julia Britton is still turning out saleable scripts. "I thoroughly enjoy writing," the 95-year-old said. "I'm a fast writer with lots of ideas."
Britton is not the sort of wizened wunderkind that Canadian psychologist Norman Doidge holds up as an exemplar of neuroplasticity - his theory that the brain is more an organism than a machine and is wearied by lack of use rather than wear.
Doidge, whose book The Brain that Changes Itself tops non-fiction bestseller lists, takes as his poster people those who don't just refuse to retire but who rage against the dying of the light by taking on new careers, new hobbies, new challenges.
"If you go and dance all the old dances, that won't help your brain - but new dancing will," the Columbia University professor said while on a visit to Sydney. "It will improve your balance and your left-right co-ordination and the mild cardio exercise will trigger the growth of new brain cells."
Imagine that: new cells, newly minted cerebral computing power.
Rather than wearing out, Doidge argues, the brain is like a muscle that atrophies when it's not exercised but grows when it is. He's committed to overturning the old paradigm of brains being like machines that will eventually malfunction.
"Machines do many glorious things, but they don't rewire themselves and they don't grow new parts," he said. "And it turns out that that metaphor was actually just spectacularly wrong and that the brain is not inanimate - it's animate and it's growing, it's more plant-like than machine-like - and it actually works by changing its structure and function as it goes along."
People unfortunate enough to suffer a retinal detachment find that after a few difficult months their brains work out that one eye is not working properly and so switch off the distorted signals received from it.
Those who suffer strokes find their brains can come to deal with the infirmities and lessen the disability.
It's not necessary to wait for a catastrophe before the brain limbers up to deal with it. Doidge urges people to keep exercising their brains rather than wait for bad things to happen.
"It seems to me just common sense that, just as a person would want to do cardiovascular training in their 50s, 60s and 70s, that you'd want to do some brain training as part of it - especially when the studies are showing that you can really turn the memory clock back so significantly," he said.
So, turn the memory clock back: learn a new language, take up the classical guitar, paint portraits, get on Facebook.
