Joni Mitchell is suffering from a "traumatic brain injury".
The 'A Case of You' hitmaker was hospitalised after being found unconscious at her home and her friend David Crosby says she had an aneurysm and is currently unable to speak.
He told Huffington Post Live: "To my knowledge she is not speaking yet. She is home, she is in care, she is recovering. She took a terrible hit.
"She had an aneurysm, and nobody found her for a while. And she's going to have to struggle back from it the way you struggle back from a traumatic brain injury."
Meanwhile, a statement on the 71-year-old singer's official website recently dispelled rumours she was in a coma.
It read: "Contrary to rumors circulating on the Internet today, Joni is not in a coma. Joni is still in the hospital - but she comprehends."
A previous statement asked for fans to "light a candle" and send their good wishes.
It read: "She is currently in intensive care undergoing tests and is awake and in good spirits. More updates to come as we hear them.
"Light a candle and sing a song, let's all send good wishes her way. (sic)"