Claire Robertson was in the changing room at her local swimming pool when she glanced up to see a woman looking at her. The woman had a nice face — warm, searching blue eyes; a hesitant smile — but seemed unsure of what to say. This often happens to Claire, a 49-year-old former nurse who six years ago suffered brain damage due to a rare viral infection called herpes encephalitis. Now an amnesiac who is unable to recognize faces, Claire lives in a world in which even her lifelong friends appear as strangers. Her husband Ed wears a distinct shark-tooth necklace at all times to help her identify him. Memory is so foundational to friendship that even those aware of Claire’s brain injury often wait a second or two upon seeing her before reintroducing themselves, hoping their presence might spark a flicker of recognition — which of course it never does. Claire assumed that was the case with the woman across from her in the changing room. But the woman continued to hover, not saying a word. Claire looked up again; this time the woman looked at her with an anxious expression. Claire decided to introduce herself. And that’s when she understood: she was walking toward a mirror. The anxious, unsure face that was staring at her was her own. There is no cure for Claire’s memory loss. The brain remains far too complex an organ for modern medicine to master, let alone reanimate after parts of it die off. Primitive memory aids — diaries, photo albums, reminder alerts on electronic devices — remain the most effective tools for helping amnesiacs like Claire cope with their condition. But the technology available to neuropsychologists is evolving fast, and Claire is among the first brain-injury patients to benefit from something as simple as a camera — albeit a very special one. The portions of Claire’s brain most damaged by the virus are known as the hippocampi, two deep, seahorse-shaped structures where new memories are formed and others are retrieved. Destruction of the hippocampi causes memory loss but only of a particular kind. Claire, like most such amnesiacs, retains a functioning procedural memory. She remembers, for instance, how to drive a car, and she could learn to play the piano if she wanted, although she would have little or no memory of receiving lessons. Likewise, Claire’s so-called semantic memory remains largely intact; her brain has preserved previously learned facts
