Rep. Gabrielle Giffords now breathing on her own

Rep. Gabrielle Giffords made major progress over the weekend. Doctors have upgraded her medical status from critical to serious condition, eight days after being shot in the head at a public event in Tucson.

Today on American Morning, CNN Senior Medical Correspondent Elizabeth Cohen explains how Giffords breathing on her own is a major step in recovery. Cohen also previews the next steps of recovery process.