U.S. Congresswoman Gabrielle Giffords of Arizona, who was seriously wounded in Saturday's shooting incident in Tucson, Arizona, was breathing on her own three days after being shot in the head, doctors said on Tuesday.

The congresswoman is recovering from a devastating head wound she suffered when a gunman opened fire at point-blank range on Saturday morning, The Arizona Republic reported.

"I'm happy to say she is holding her own," Michael Lemole, University Medical Center's chief of neurosurgery, said at a briefing on Giffords' condition. "She is able to follow simple commands."

Lemole said doctors are keeping a breathing tube in Giffords to clear her airways of fluids and to prevent other medical problems such as pneumonia.

"She is breathing on her own. The only reason we keep that breathing tube in is to protect her airway," Lemole said.

In addition to Giffords, five patients remain in the hospital with three listed in serious condition and two in fair condition after the shooting rampage, the report said.

Giffords was presumably the major target in the shooting, which killed six people. In addition to Giffords, 13 others were wounded.

Giffords' brain swelling has remained at about the same level as a day ago -- a good sign, doctors said, because such swelling is the most significant risk for head-trauma patients. Doctors removed nearly half of her skull to allow the brain to freely swell and heal itself.

Dr. Peter Rhee, University Medical Center's trauma director, said after the news conference that he is positive that Giffords won't die and likely will avoid a vegetative state. But he said it 's too early to tell how quickly and to what degree Giffords will recover.

She continued to follow simple commands to lift fingers and her thumb, and she moved parts on both sides of her body, Rhee said.

In a related development, President Barack Obama and First Lady Michelle will travel to Tucson on Wednesday along with three top federal officials -- Attorney General Eric Holder, Associate Supreme Court Justice Anthony Kennedy and Homeland Security Secretary Janet Napolitano, according to the report.

They will attend a memorial event at the McKale Center on the University of Arizona campus.

Obama said earlier that his administration was keeping in touch with families of the victims, Arizona Governor Jan Brewer and congressional leaders, and that there is "no doubt" that plans for a memorial will evolve over the next several days.

"It's going to be important, I think, for the country as a whole, as well as the people of Arizona, to feel as if we are speaking directly to our sense of loss, but also speaking to our hopes for the future and how out of this tragedy we can come together as a stronger nation," Obama said.