Lamar Odom Being Weaned Off Life Support

Lamar Odom was able to breathe on his own, with the help of a mask rather than a ventilator ... TMZ has learned.

Our sources say doctors are trying to get Lamar functioning on his own, so a few minutes before this story was posted, they took him off the ventilator and put a breathing mask on Odom.

We're told doctors are putting him back on the ventilator and used the mask as a test, and they plan on going back and forth to see if Lamar would be able to breath without heavy life support.

It's another hopeful sign. As we reported, tests Friday morning revealed Lamar's heart has shown some improvement. That said, our sources were quick to add Lamar is not out of the woods by any means, and it's unclear if he'll be able to sustain breathing on his own.