LOS ANGELES (CBSLA.com) — A Harvard sleep expert was on the stand all day in the Michael Jackson wrongful death trial, called by the Jackson family attorney to testify about the affect sleep deprivation had on the late superstar.

Dr. Charles Czeisler, who specializes in sleep study, told jurors in Los Angeles Superior Court the anesthetic propofol Conrad Murray administered to Jackson to help him sleep in the weeks prior to his death prevented the star’s brain from getting the rest it needed to allow him to perform.

READ MORE: USC To Conduct Zero Waste Game Saturday Evening

Czeisler testified that unlike other drugs used in anesthesia, propofol will “dissipate the drive for sleep”.

He also listed a number of side-effects that could result from lack of sleep, including reduced levels of judgment and a disheveled physical appearance.

Jackson died on June 25, 2009 after he received a dose of propofol administered by Murray and stopped breathing.

READ MORE: 4 People Shot At Willowbrook Metro Station, 3 Of Those Critically Injured

He was preparing for his This Is It comeback concert series at the time.

Jackson family attorneys are trying to convince the jury that executives at concert promoting giant AEG Live were negligent in hiring and supervising Murray, who was convicted of involuntary manslaughter in Jackson’s death.

Murray is currently serving a four-year sentence in a L.A. County jail for providing the fatal dose.

MORE NEWS: Thousands Participate In 'More Than Pink' Walk Raising Awareness, Funds In Fight Against Breast Cancer

(©2013 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)