Ted Turner has Lewy body dementia, a progressive brain disorder, the CNN founder tells Ted Koppel in an interview to be broadcast this weekend on CBS Sunday Morning.

"It's a mild case of what people have as Alzheimer's. It's similar to that. But not nearly as bad. Alzheimer's is fatal," Turner, 79, tells Koppel in an excerpt of the interview released Friday by CBS News. "Thank goodness I don't have that. But, I also have got, let's — the one that's — I can't remember the name of it."

After a pause, according to CBS, Turner said, "Dementia. I can't remember what my disease is."

Evidence of Lewy body dementia was found in the  autopsy of comedian Robin Williams, who died by suicide in 2014 after reportedly experiencing a bewildering series of mental and physical symptoms.

Turner, who was interviewed on his ranch in Bozeman, Mont., reported his symptoms to be forgetfulness and fatigue. But as CBS News notes, he has  been "known for going through euphoric highs and dark lows, which were initially diagnosed as symptoms of manic depression. Turner says that was a misdiagnosis."

Lewy body was a plot point in the 2011-12 Starz drama Boss, in which Kelsey Grammer starred as a fictional Chicago mayor who was trying to hide his diagnosis while experiencing symptoms that included hallucinations. The actor also participated in a public-service campaign for the Lewy Body Dementia Association to promote awareness of a condition that's believed to affect some 1.3 million Americans.

Other topics of Sunday's interview include Turner talking about the current state of his former  network — he thinks "they're stickin' with politics a little too much" — and the idea Turner once had to run for president.

"Well, the closest I came to running for office was when I was married to Jane Fonda. And when I discussed it with her — she was married to one politician," Turner tells Koppel, as reported by CBSNews.com. "And she said, you know, 'If you run for, for office, you run alone.'"