Ted Turner has revealed his Lewy Body dementia diagnosis.

The 79-year-old media mogul, who founded CNN in 1980, opened up about his illness for the first time during an interview with CBS Sunday Morning in a clip that was released on Friday.

“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 said of LBD, which is caused by abnormal protein deposits that build up over time and disrupt normal brain function.

“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,” he said, pausing momentarily before adding, “Dementia. I can’t remember what my disease is.”

Turner, who filmed the interview at his 113,000-acre ranch near Bozeman, Montana, also described his symptoms of feeling “tired [and] exhausted. That’s the main symptoms, and forgetfulness.”

LBD is the same disease Robin Williams was suffering from before he died of suicide in August 2014 at age 63, according to his widow Susan Williams.

RELATED: Robin Williams and the Brain Disorder That Drove Him to Suicide: What Is Lewy Body Dementia?

“Lewy Body dementia is the second most common neurodegenerative dementia after Alzheimer’s,” Dr. Alex Pantelyat, Director of Atypical Parkinsonism Center and Assistant Professor of Neurology at Johns Hopkins previously told PEOPLE in November 2015. “It is an incredibly devastating disease. It affects your core, it affects who you are as a person. In the case of DLB and some of these other related disorders it tends to a great extent affect the frontal lobe, which is really what makes us human. It’s really unbelievably devastating.”

Turner was most recently featured in his ex-wife Jane Fonda‘s HBO documentary Jane Fonda In Five Acts, which premiered on Sept. 24.

After 10 years of marriage, Turner and Fonda divorced in 2001.

“[Ted] was sexy. He was brilliant. He had two million acres by the time I left. It would have been easy to stay,” she told PEOPLE editor-in-chief Jess Cagle, in the most recent episode of the Jess Cagle Interview.

“But there was this angel on my shoulder. …It was hard to even hear her voice, saying, ‘If you stay, you will die without ever becoming who you can be. You will not really be authentic,’ ” she said.

Turner’s full interview will air on CBS Sunday Morning at 9 a.m. on Sunday.