CLAREMONT (CBS/AP) — President Barack Obama led a shocked nation in a moment of silence Monday morning for the victims of the Arizona shootings and their families.

LA Congressman Xavier Becerra Talks With KNX 1070

Meanwhile, 22-year-old Jared Lee Loughner faces a federal court hearing on charges that he tried to assassinate Rep. Gabrielle Giffords.

Six people died in the rampage that left Giffords critically wounded.

Students at Scripps College in Claremont, where Giffords earned her degree, also paused to honor her Monday morning.

Doctors are optimistic about her odds, but it can take weeks to months to tell the damage from a gunshot wound to the head.

Doctors say the bullet traveled the length of the left side of Giffords’ brain, entering the back of the skull and exiting the front.

Fortunately, it stayed on one side of her brain, not hitting the so-called “eloquent areas” in the brain’s center where such wounds almost always prove fatal.

Importantly, Giffords was responding nonverbally Sunday to simple commands in the emergency room — things like “squeeze my hand.”

That implies “a very high level of functioning in the brain,” said Dr. Michael Lemole of Tucson’s University Medical Center, Giffords’ neurosurgeon.

Now, her biggest threat is brain swelling. Surgeons removed half of her skull to give the tissues room to expand without additional bruising, Lemole said.

That bone is being preserved and can be reimplanted once the swelling abates, a technique the military uses with war injuries, added his colleague and trauma surgeon Dr. Peter Rhee.

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