Sheryl Crow opened up about her battles with a brain tumor on the first episode of Katie Couric's new talk show.
Crow, who wrote the theme song for the nationally syndicated "Katie," told the former morning show host that frequent cell phone use led to the singer's brain tumor.
She couldn't point to any medicinal proof to back up her claim - "there are no doctors who will confirm it," she admits. She insists using older model cell phones while doing promotional phoners had a negative impact on her health.
The singer says it became difficult to carry on normal conversations ... claiming she felt "mushy" ... and at one point she was convinced she had early onset Alzheimer's.
Later, she learned she had a benign tumor the size of her pinky that's located between her skull and the lining of her brain.