Shot politician Gabrielle Giffords was "even more alert" and progressing well, her chief doctor said, a day after beginning intensive rehabilitation in Houston, Texas.
Dr Gerard Francisco of Texas Medical Centre said the 40-year-old Arizona congresswoman did not speak or make any sounds when he examined her, but that could be because she still has a breathing tube.
He said it was too soon to say whether she could or would be able to talk.
Democrat Ms Giffords was shot in the head in an attempted assassination on January 8 while meeting constituents in Tucson.
Six people died in the rampage, including Arizona's top judge John Roll, and 18 other people were injured.
The suspected gunman, Jared Loughner, 22, is in federal custody.