As a veteran reporter who now has her own TV show on OWN, Lisa Ling has covered everything from criminal informants to exorcism.

It was while filming an episode of "Our America With Lisa Ling" on the topic of Attention Deficit Hyperactivity Disorder (ADHD), however, that she made a personal discovery.

"My head is kind of spinning," Ling, 40, said after receiving a diagnosis of attention deficit disorder (ADD) herself while the cameras were rolling. "But I feel a little bit of relief because, for so long, I've been fighting it and I've been so frustrated with this inability to focus."

Ling, the mother of one young daughter, says on the show that she had long suspected something was not right.

"As a journalist, when I'm immersed in a story, then I feel like I can laser-focus. But if I'm not working, my mind goes in every direction but where it's supposed to go," Ling says. "I've been like that since I was a kid."

Ling's diagnosis of ADD at age 40 is unusual, experts say, compared to the average age of diagnosis at seven.

"ADD is more accepted now than 10 or 20 years ago," said Dr. Edward Hallowell, a psychiatrist and ADD/ADHD specialist, who does not treat Ling. "People don't think of ADD in adults."

"The diagnosis can dramatically change your life for the better," Hallowell said. "You can go from languishing to succeeding at the highest level."

In a statement, Ling says the diagnosis of ADD has given her "clarity."

"While the diagnosis confirmed what I had always expected, I don't feel inhibited," she said. "Rather, I feel I have more clarity."

"Our America With Lisa Ling" airs Thursday at 10 p.m. ET on OWN.