Michael Jackson reportedly didn't sleep properly for two months before his death.

The King of Pop passed away from Propofol intoxication in 2009 but according to Dr. Charles Czeisler, a Harvard sleep researcher testifying during Michael's mother Katherine's wrongful-death suit against concert promoter AEG Live, he would have died a few days later anyway from the lack of rapid eye movement (REM) sleep.

He explained that lab rats exposed to the same lack of REM often died after five weeks.

Dr. Czeisler said: ''The symptoms that Mr. Jackson was exhibiting were consistent with what someone might expect to see of someone suffering from total sleep deprivation over a chronic period.''

Adding that Propofol injections by Michael's doctor Conrad Murray did not help him adequately rest, he said: ''It would be like eating some sort of cellulose pellets instead of dinner. Your stomach would be full and you would not be hungry, but it would be zero calories and not satisfy any of your nutrition needs.

''Like a computer, the brain has to go offline to maintain cells that we keep for life, since we don't make more. Sleep is the repair and maintenance of the brain cells.''

However, lawyers acting for AEG Live said it was Michael who hired Dr. Murray and they had no idea he was treating Michael with Propofol.