In 2009, after Nelson Dellis's grandmother Josephine passed away from Alzheimer's disease (which may have a hereditary component), he was inspired to find ways to keep his own brain healthy and sharp.
"I was a good student, but my memory was average," Dellis, 35, tells CNBC Make It.
Dellis scoured the internet looking for tips to improve his memory and joined a few forums where professional "memory athletes" (people who train their memory skills for high performance) chatted about different memory techniques. Then he listened to "Quantum Memory: Learn to Improve Your Memory with The World Memory Champion," an audiobook by Dominic O'Brien, a seven-time world memory champion.
"After that, I went off and, through trial and error, figured out what [techniques] worked well for me," Dellis says.
Today Dellis, author of the book "Remember It" and a four-time USA Memory Champion (an annual competition for elite mental athletes), is a full-time memory coach based in Miami, Florida. He charges $250 an hour for private lessons to the likes CEOs and billionaires, including Mark Cuban and Sara Blakely.
Here are Dellis' top three tips on improving your memory and staying sharp.
Dellis says one the easiest memory tips that he's learned over the years is to take time to totally disconnect from technology — including your smartphone — for at least an hour a day.
That's because presence is important for memory, says Dellis.
"Your brain is a processing unit," he says. "If your brain isn't present to receive [information] (i.e., you're distracted and not paying attention), how on earth do you think it's going to be able to remember it? You'll be surprised how powerful your natural memory is if you just try and pay attention."
Dellis's advice is supported by research: According to a 2017 study from the McCombs School of Business at The University of Texas at Austin, researchers found the mere presence of a smartphone reduces cognitive capacity, affecting one's brain to hold and process data.
"My goal whenever I memorize something is to turn it into a mental picture in my mind," he says, which is "any mental representation of what you're trying to memorize, using as many of your senses as possible." It could be an association, a sound, a feeling — anything that's "meaningful" to you, Dellis says.
That's because it's much easier to remember a picture of something that you are familiar with than words relating to something new and difficult, he says. (Studies in older adults have shown that pictures can help with memory.)
Dellis uses the example of remembering the name chervil (an herb) to buy at the grocery store.
"Most people might not even know what that is. So I might break that word down into what it sounds like: 'sure-vill.' So maybe my meaningful image could be, me saying 'sure!' enthusiastically to a 'vill'ain. The more context the better. Maybe I'm agreeing with this villain, because if I don't, he'll take all the chervil in the world and secretly garnish all the food in the world and ruin the taste of everything," Dellis says.
The "more over-the-top and bizarre you make the image, the better."
To practice, Dellis suggests that when you meet someone for the first time, turn their name into mental images, as he did with chervil.
"You'll have a higher chance of remembering the person's name, and you'll be training your brain to get better/quicker at thinking in pictures," he says.
When you're thinking in pictures, you need a place to store those images. So most memory athletes use a technique called the "memory palace," according to Dellis. The technique (which dates back to the ancient Greeks) has to do with remembering things based on location
According to Dellis, a memory palace works like this: Think of a familiar place (like your house, apartment, office, etc.) and imagine a mental pathway through it. To store your images, simply imagine or "stick" each image on a location along the path in your mind. The idea is that later on when you want to retrieve the information, all you have to do is think of your memory palace, walk back through it in your mind and pick up the images you left there.
It sounds a bit crazy, but it works, according to Dellis and it allows top memory athletes to memorize thousands of pieces of information, he says.
"It's an effective way of stringing together sets of memories because it uses more and various parts of the brain than simply short term recall (visual, emotional, language, imagination and short term memory)," neuroscientist Tara Swart tells CNBC Make It.
To practice, Dellis suggests choosing three familiar places and selecting 10 locations along your mental path through each. Start by storing daily to-do lists and grocery lists there as practice.
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