Doctors say Arizona congresswoman Gabrielle Giffords has been told by her husband that she was shot, but has no memory of the day a gunman in Tucson opened fire on her and a crowd of supporters two months ago.

Medical staff for Giffords provided an update on her progress Friday at a news conference in Houston. They said she is making "leaps and bounds" in her recovery from being shot in the head on Jan. 8, and is walking and talking in complete sentences.

Doctors also said they have removed Giffords' breathing tube, a big step forward in her recovery. Dr. Imoigele Aisiku described the tube removal as a "fist-pump" moment.

"It's a good possibility that she will be able to attend her husband's space shuttle launch next month," said Dr. Dong Kim.

Gifford's husband, astronaut Mark Kelly, will be the commander of Endeavour when it launches into space on its last trip.

At some point in May, Kim said, doctors expect to reattach a flap of her skull that had been removed to ease pressure on her brain, but that she can travel before that happens.

Alleged gunman Jared Loughner, 22, pleaded not guilty to fatally shooting six people in a Tucson grocery store parking lot and wounding 13 others, including Giffords.