To maintain a healthy brain and sharp memory, I avoid this one thing as a neurologist.

A healthy diet, good sleep hygiene, frequent exercise, and another important factor are crucial for brain health, according to Dr. Richard Restak, a clinical professor of neurology at The George Washington University School of Medicine and Health Sciences.

Restak, 82, has authored over 20 books on the brain, including "The Complete Guide to Memory: The Science of Strengthening Your Mind," which provides evidence-based strategies to enhance memory and maintain cognitive function.

What does Restak do to maintain a healthy brain?

"I strive to stay active and make learning new words and memory exercises enjoyable, as Restak suggests."

'Avoid boredom, stay challenged'

He's currently writing a book and has another one planned "if he chooses to do it."

Restak performs a memory exercise every morning while walking with his dog. On the day we spoke, he created a list of 10 words and wrote them down before leaving his house.

During our call, Restak recited the words he used in that morning's walk from memory.

Here's his method for memorization.

According to Restak, our primary method of recalling information is by visualizing it. The more unusual the image, and the more closely we adhere to the narrative.

Most people have a natural inclination towards storytelling, he remarks. "We enjoy listening to stories. We enjoy sharing stories. Therefore, we will remember the tale."

Restak created a brief story and linked each word to a mental image. One of the words he selected was "yo-yo," and to recall it, he envisioned a yo-yo delivering a speech in Chico, Calif., where the National Yo-Yo Museum is located.

Restak stays sharp and entertained on his morning walks by doing memory exercises.

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