In one sitting, Farrow recalled the order of 52 shuffled decks, or 2,704 cards, when he was just 21 years old. He even reclaimed the title after his record was broken, by memorizing the order of 59 decks of shuffled cards, which is 3,068 cards.
"For memory and mental focus in general, the key is novelty," Farrow, author of "Brainhacker: Master Memory, Focus, Emotions, and More to Unleash the Genius Within," tells CNBC Make It.
"The more novel something is, the more you're going to remember it. But also an activity that's very novel, and that just [means] unique or different, is something that challenges your brain more."
Here's how the world record holder increases his memory and focus.
1. Short intervals of intense focus, followed by resting periods
"We have this powerful brain, but we have a terrible battery for it," Farrow says. "The key is to trigger focus at will, not try to force your brain to focus for 24 hours."
If you're working hard to memorize something or focus on an activity, you should ebb and flow between intense focus for six to eight minutes and completely clearing your mind using meditation or deep breathing exercises for a brief period, he suggests.
"This is actually one of the secrets behind my Guinness record. I never would've been able to memorize 59 decks of cards all shuffled together if I tried to memorize it all in one go," he says.
"If you do it in short intervals, you never actually push yourself to build up so much chemistry that you need a vacation to clear your head."
2. Conversations with new people
Meeting new people and engaging in interesting conversations is stimulating for the brain and can be great for boosting memory, says Farrow.
"You have to be social. Go out and meet new people," he adds. "[For] people with Alzheimer's or dementia, or [those] who have risk factors for that, the single greatest thing they can do is be social."
3. Challenging activities
Don't be afraid to try something new, especially if you think you won't be good at it, he says. Playing a new instrument, for instance, may be challenging but even if you're not amazing at it, it's helpful for brain stimulation.
"By the time you're start sounding good, it's actually less challenging for your brain," says Farrow. "So, constantly try new things and be adventurous."
Also consider learning a new language, taking up juggling, starting a garden or changing the oil in your car if you've never done that before, he notes.
4. Looking up as often as you can
This one may be hard to wrap your brain around, but it's actually a quirky trick for boosting memory, according to Farrow.
"When you look up, it's your brain's natural tendency when it's trying to recall something," he says. "Nobody knows why, but we do know that it sends more energy to your cerebral cortex and hippocampus, all of the memory centers of the brain."
So, by looking up, "you actually improve your memory," says Farrow.
5. Deep-breathing exercises
Every so often, Farrow suggests breathing deeply enough that your chest stays in place, but your stomach moves in and out.
"You'll find that your brain changes [and] you relax," he says. This is primarily helpful if you're unable to focus or remember certain information because you're extremely stressed, he notes.
"[With] the students that I've worked on this with, when they take a few deep breaths if they're blanking out on something and it's stress-related, they generally recall the information," says Farrow.
- Standing on one foot for a while, every now and then
- Brushing your teeth with the opposite hand
- Aiming to memorize people's names and faces
"When I was a kid, I was diagnosed with ADHD and dyslexia," Farrow says. With little knowledge of those conditions at the time, people saw them as disadvantages, and initially Farrow did too.
"When I went for the Guinness record the first time, nobody believed I could do it. When I went for it the second time, they were all like, 'Oh, why didn't you do this sooner?'" Farrow continues.
"I just wanted to show people with ADHD or dyslexia that you can accomplish some great things."
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