Kendrick Lamar recently opened up about battling depression and suicidal thoughts, and how those dark thoughts influenced his music.

During a four-part interview with MTV, Kendrick spoke honestly about where, exactly, his music comes from. One song off his latest release, To Pimp a Butterfly, deals with themes of depression and suicide in particular -- the introspective, self-defeating and critical "u."

With lines like, "I know depression is restin' on your heart for two reasons," and "And if this bottle could talk / I cry myself to sleep / Cause everything is your fault / Shoulda killed yo ass a long time ago / You shoulda felt that black revolver blast long ago / And if those mirrors could talk it would say 'you gotta go' / And if I told your secrets / The world'll know money can't stop a suicidal weakness," it offers up a direct contrast to the album's uplifting, self-love anthem of a lead single, "i." And according to Kendrick, those words come from a very real, very dark place.

He said, "I've pulled that song not only from previous experiences, but, I think my whole life. I think everything is drawn out of that. Even situations from Good Kid M.A.A.D City. Nothing was as vulnerable as that record. So it's even pulling from those experiences of coming up in Compton. It's pulling from the experience of going through change and accepting change. That's the hardest thing for man -- accepting change."

The song goes on to detail Kendrick's own disappointment in himself for not being there for his family and friends when his was on tour. He said, "When I was on that tour bus and things is happening back home in my city or in my family that I can't do nothing about, it's out of my control, [and to] put it in God's hands, I couldn't understand that. That can draw a thin line between you having your sanity and you losing it. This is how artists deteriorate if you don't catch yourself."

"It's real, man," he said. "Three of my homeboys [one] summertime was murdered, close ones too -- not just somebody that I hear about. These [are] people I grew up with. It all, psychologically, it messes your brain up. You live in this life...but you still have to face realities of this. I gotta get back off that tour bus and go to these funerals, talk to my mom and talk to their aunties -- the kids that lost their lives."

Kendrick also spoke to Rolling Stone about the song, saying, "That was one of the hardest songs I had to write. There's some very dark moments in there. All my insecurities and selfishness and letdowns. That shit is depressing as a motherf---er. But it helps, though."

You can check out the full MTV interview in the video above.