Loneliness increases risk of memory loss in older adults

Respondents who were socially isolated and lonely experienced the greatest decline in memory. But loneliness alone, not social isolation, had the second greatest impact on memory.

While social connections have been proven to keep you sharp and happy as you age, it’s just as important to stay mentally active whether or not you’re surrounded by people.

“The brain never finishes wiring itself,” said psychologist and neuroscientist Dr. Lisa Feldman Barrett during the course “The Science of Aging Smarter.”

Your brain’s ability to change the wiring of its neurons, also called plasticity, lasts your entire life. This means you can learn new skills at any time.

One way to improve your brain’s plasticity is to try new things.

“Anytime you encounter something that you didn’t anticipate or plan for, and it might be useful in the future, your brain is going to try to learn it,” Barrett said. “And learning is plasticity.”

Activities like traveling, learning a new language, or reading a book can all improve your brain health.

Physical activity can also stimulate brain cell growth, Dr. Wendy Suzuki, a neuroscientist and dean of New York University’s College of Arts and Sciences, told CNBC Make It.

“Forms of activity that require strategy will engage your prefrontal cortex more,” she said.

Of course, having stimulating social relationships isn’t entirely useless. In fact, meeting new people can also improve brain plasticity.

“All of these things represent a metabolic challenge today,” Barret said. “But they represent an investment in a healthier, stronger life.”

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