John Thackray, a retired business journalist and active mountain climber, vividly recalls "the most cognitively difficult thing I ever did in my life." It was 1979, and he was leading the first ascent of Thalay Sagar, a 22,000-foot peak in the Indian Himalayas. While rappelling down after five days on the mountain, his rope jammed. Thackray had to figure out a complex gear maneuver he'd never done, to unjam himself before cold and exhaustion rendered him senseless. "You pull out the idea from someplace deep within you," he says. "And you better get it right."
Cognitively speaking, Thackray is what University of Florida cognitive neuroscientist Adam Woods calls a SuperAger, someone who at 82 is pretty much as sharp as he was when he climbed Thalay Sagar. No doubt those wits have kept Thackray alive in the mountains, and constant exposure to mentally and physically challenging situations has helped him maintain his mental edge.
For most of us, however, cognitive rot can set in surprisingly early. In one broad aging study, a number of subjects showed significant drops in cognitive test scores by their late thirties. Between the ages of 25 and 75, our ability to put the right name to the right face, or what neuropsychologists call face-name recognition, drops by half. Raffaele says this type of age-associated memory loss is the most common complaint he hears from his patients who are 40 and older. The problem isn't that neurons are dying off; it's that the thin myelin sheath protecting them begins to degrade, making it harder to create synapses between neurons that allow mental connections.
At the other end of the spectrum from Thackray and SuperAgers are the roughly 17 percent of people who, by middle age, experience enough of a mental slowdown to qualify for a diagnosis of mild cognitive impairment (MCI). "A much higher percentage of people who have MCI will convert to Alzheimer's disease," says University of Alabama psychologist Karlene Ball. There's no perfect way to define MCI and Alzheimer's, but this old saw holds true: If you habitually can't find your keys, you may have MCI. If you can't remember what the keys are for, it's Alzheimer's.
No one wants to think about developing Alzheimer's. But Raffaele says it's better to know where you may be headed so you can act on it, and memory and processing speed tests can tell you if you're on that path. Based on my lousy memory scores, that's me. (The only reason my Neuro Age isn't alarming is that Raffaele bases it on processing speed, which is the aspect most tightly linked with aging.) Thankfully, many lifestyle tweaks have been proved to defend against cognitive weaknesses. And myriad studies show that people do better on cognition tests after they adopt these brain-building habits.
No one will be sharper at 80 than he was at 30, but everything we know says that taking protective measures will help reduce the likelihood, or at least the severity, of MCI. Does that mean we can sidestep Alzheimer's? "That's the hope," says Woods. Considering my own memory issues, I'll take it.
How to Lower Your Cognitive Age
Despite what you may have heard, crossword puzzles don't stave off cognitive decline. Instead, Woods says, do new things you're not naturally good at, such as painting, learning a musical instrument, or playing a new sport. It will feel frustrating because you're exercising mental "muscles" that are out of shape. "But that's a good thing," Woods says, "like soreness after a hard workout." Call it cognitive cross-training. "These are complex activities that stress multiple cognitive systems and enhance the connections between neurons," he adds.
After Hernandez, the middle-aged Florida businessman, cranked his strength and cardio sessions from virtually nothing to six days a week, his cognitive test scores jumped from percentiles in the 80s (good) to those in the high 90s (superb). The real-world payoff: "I was more relaxed and much more efficient at work," he says. Age-management physician Steven Masley, who oversaw Hernandez's transformation, later published a study showing cognitive jumps in people who worked out five times a week versus those who did so only twice.
Research-backed brain-boosters: coenzyme Q10, acetyl-l-carnitine, phosphatidylserine, and omega-3s.
Here is your guide to assessing — and slowing — everything from your cognitive age to your metabolic decline.