An elderly couple I knew lived together in a nursing home well into their 90s.
He had advanced dementia, inhabiting a world separate from reality, but physically he was strong and healthy.
She was physically frail and unsteady, with constant pain and suffering from chronic diseases. But her mind was not impaired at all, and she could engage with the world and express herself clearly.
We marvelled at how each compensated for the other's disabilities.
And yet, anyone over 40 who knew the couple couldn't help thinking, "Which loss would be worse for me? Loss of a functioning, healthy mind? Or loss of a functioning, healthy body?"
"I think that people fear both," says Dr. William Reichman, president and CEO of Baycrest, a world-renowned centre for studying and treating diseases of aging.
And we're right to fear both. Because, except for a lucky few, most people who reach a great age will be in a "state of fairly severe physical and mental frailty," Reichman says.
"We will ultimately get more frail physically and mentally if we live long enough."
The good news?
Dire as it sounds, it's a happy thought. It means we'll be spending a shrinking percentage of our overall lifespan in that state of physical and mental frailty.
"There is," Reichman says, "the ability to hold at bay some of the things we thought inevitable as we get old."
Until now, that's been mostly true for the physical fallout of aging, particularly musculoskeletal and cardiovascular health: joint replacements, steroids, blood thinners, statins, stents and more.
But Reichman promises, "What we did for heart health in the 20th century, we can do for brain health in the 21st century."
At Baycrest's Rotman Research Centre and in other centres around the world, scientists are using imaging technology that's been developing over the last decade to focus on prevention: understanding the risk factors of brain failure and how to support brain health.
As with reducing mortality from heart attacks and heart failure, it's early intervention that makes a difference. "By the time you show symptoms, you're already in a pretty advanced stage of brain failure," says Reichman.
A major motivation for the focus on prevention is the threat of a "coming epidemic of dementia."
Already, 30 to 40 per cent of people over the age of 80 are suffering from dementia. And, with more and more people living over the age of 85, the prevalence of dementia, with Alzheimer's being most common, is going to double.
It's no wonder that what scares us leading edge boomers most, even more than losing our mobility, is losing our minds.
I have an aunt in her 90s, the last family member of the generation ahead of mine, who lives in a nursing home and stands at the dementia unit's locked door at the end of every day, a frightened child trying to get out to find her mother in Moldova, the place she left when she was seven.
Next up is my generation.
And so I was overjoyed to learn about some of the research at Baycrest that just might help keep my mind sound as the decades continue to accumulate.
Working at the deepest, broadest and perhaps most profound level, in the emerging field of population neuroscience, is a couple new to town.
Dr. Tomas Paus, working with his wife, Dr. Zdenka Pausova who is based at SickKids, will screen generations of Toronto families in different ethnic communities to learn how environment, culture and genes interact to shape the human brain and body.
"Obesity, cardiovascular disease, metabolic disorders – most are complex traits," he explains, "and not just (caused by) a single gene or even multiple genes in isolation from the environment.
"And it's pretty much the same for disorders of the brain, psychiatric disorders, depression. It's multiple genes interacting with environment."
For example, he says, the probability of depression can be affected by your genetic component for serotonin interacting with the number of stressors and stressful events that occur in your environment and in your life.
Researcher Nicole Anderson is leading a brain imaging study with both healthy aging adults and adults with mild cognitive impairment to see if cognitive rehab training can help people improve their cognitive powers.
And scientist Carol Greenwood is researching how diet impacts brain function, and the relationship of Type 2 diabetes to cognitive function.
As someone who spent hours every day practising the piano all through my school years, I was especially glad to talk to psychologist Claude Alain whose research involves how musical training impacts brain circuits.
Hearing decreases as we get older, he explains, and one of the more common complaints is trying to have a conversation in a noisy setting – in other words, sorting out and separating sounds.
Researchers aren't sure whether this is related to the mechanics of the ear itself, or whether it's a function of the brain's loss of ability to concentrate.
"So we came up with this idea to look at whether musical expertise and training has an impact on how you process or solve complex auditory problems," he said.
Preliminary findings, he says, suggest that "the rate of decline is shallower in musicians" and that "musical expertise or training does alleviate some of the change in auditory perception."
More and more, scientists are telling us what poets already put forth: That in the end is the beginning and that how and where we finish up is determined by the path we followed on the way.