A sleep expert testifying in the trial of Doctor Conrad Murray, who is accused of involuntary manslaughter in the death of Michael Jackson, suggested that Murray experimented with the pop singer.

Dr. Nadar Kamangar, a sleep expert, testified before jurors Thursday that the drug Popofol which Murray used to treat Michael Jackson's insomnia was never approved for use as a sleep aid.

Murray's treatment amounted to "an experiment," said Kamangar today.

Defense attorneys cited research from Taiwan in which patients with insomnia were treated with propofol, but Dr. Kamangar said the study was from 2010, a year after Michael Jackson was dead.

The trial will continue Monday October 17.