So many comic greats have made us laugh while suppressing their own demons. Just like Robin Williams, they all share one thing in common -- they use comedy to mask the pain behind the punchline.
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"It's almost like a drug, because you get this kind of immediate adrenaline rush, especially if you're finding stuff," Robin said in 2006.
Dr. Phil McGraw explained the appeal that making people laugh has for comedians, saying, "As long as [the audience] is laughing and talking, they're not focusing on them, so it doesn't really get healed."
"I didn't want anyone to know about me," Robin said in 1986. "I didn't want people to know the quiet side or any other side, because of fear of what they would do with it."
Laugh Factory founder Jamie Masada, who has seen many comic legends come and go, told ET's Nancy O'Dell that Robin kept up a happy façade until the end.
"He always masked [the pain]," said Jamie.
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Legendary Comedy Store comedians such as David Letterman, Richard Pryor and Jim Carrey have also had publicized battles with depression.
Letterman explained his experience during a sit down with Oprah.
"You can't stand looking at the sunlight," said Letterman. "You can't wait to get back in bed at night; you're shaking; you're shivering."
Letterman continued working through his dark periods, saying that he just "pushed through it."
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