The congresswoman’s recovery, documented on video, shows how a brain reconstructs itself.

At seven weeks, Giffords crinkles her nose to say no. She squints wryly at Kelly. She pokes fun at herself. “Goofball Giffords,” she says.

Finally, at 10 months, Giffords sits down for an ABC interview. Her voice is strong, her eyes full of life. She reaches over to fix Diane Sawyer’s hair. Giffords’ vocabulary is much improved. She says moving her right arm is “difficult,” despite “two hours of therapy” every day. She looks at a picture and pronounces it “beautiful.” Thinking back to the people who died at the scene of her shooting, she finds the word she couldn’t summon earlier: “sad.” She gropes for simple terms to express her feelings: “Better. Stronger. Hard.” And for her husband: “Brave.”

The interview shows how extensively Giffords has recovered. “Awful,” she snorts when Kelly jokes that she likes football. “Stinks!” she adds. But the most remarkable thing caught on camera is her struggle to regain what’s still missing. When Sawyer asks Giffords whether she really thinks she can return to Congress, Giffords, at a loss for words, shapes her hand into a gesture that conveys what she wants to say. Giffords’ face is tight with concentration and effort, her eyes locked on her hand. She seems to be speaking in sign language, but not to Sawyer or anyone else. The brain, through the hand, is rewiring itself.

What you see in Giffords is what researchers are learning about the mind. Right now, at the annual meeting of the Society for Neuroscience, 30,000 humans are swarming around the Washington, D.C., convention center, exchanging the latest discoveries about neurons, receptors, and circuits. What they’re finding everywhere is plasticity. The brain isn’t built once. It rebuilds itself, day after day, editing a network of 100 trillion synapses that absorb, represent, and manage experience. It makes us who we are. And, when necessary, it remakes us. Just ask Gabby Giffords.

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