MARY LOUISE KELLY, host:
Now, to another story about the human voice. NPR's Alix Spiegel talked to a man who has phonagnosia, literally translated from Greek as sound not knowing. It's a disorder which makes people completely unable to recognize voices.
ALIX SPIEGEL: As a boy growing up in Northern Virginia, Steve Royster was confronted with a small, but persistent mystery - a mystery that presented itself every time he used the phone.
Mr. STEVE ROYSTER: Everyone always knew when I was calling just by the sound of my voice, while I had no earthly idea who was on the phone when they called.
SPIEGEL: Royster couldn't understand this. It made no sense. Really, there was only one possible explanation.
Mr. ROYSTER: I thought I had such a distinctive voice that everyone could recognize me the second I spoke on the phone. That was the best I could come up with.
SPIEGEL: In fact, Royster has phonagnosia, or voice blindness, a very rare and very strange disorder. Like everyone else, phonagnosics can tell from the sound of your voice if you're male or female, old or young, sarcastic, upset, happy. They just can't tell who you are.
Mr. ROYSTER: Not that every voice sounds the same to me. It's just that hearing someone's voice doesn't bring that person to mind.
SPIEGEL: According to phonagnosia researcher Diana Sidtis, the part of the brain that allows people to distinguish things like age, gender and emotional content in a voice is different from the part of the brain that makes sense of whether or not the voice they're hearing has personal relevance, the part that's able to determine when something is familiar.
In phonagnosia, that part of the brain is damaged. So if they can't see you, they can't place your voice. This is why Steve Royster never knows who's calling him, even when the voice on the other end of the line is his own mother.
Mr. ROYSTER: I'm often at a loss, and I have to fake it.
SPIEGEL: So what do you do to fake it?
Mr. ROYSTER: I just continue to say, well, that's nice, and eventually hit on something about the house or one of my brothers, and that will clue me in that this strange woman who has called me is, in fact, the one who gave birth to me.
SPIEGEL: While for some people having phonagnosia is genuinely difficult, Royster says for him it falls into the category of minor annoyance. In fact, he didn't even know he had it until he was 27 and started sharing a small office with a coworker.
Apparently, one of his bosses would frequently call him up and start barking orders without ever identifying himself, while Steve - who had no idea who it was - just sat there, flummoxed.
Mr. ROYSTER: And after hearing my end of several of these conversations and my complaints after I would get off the phone that, well, why is this guy calling? He just said so, well, you recognize his voice don't you? I said well, no, how could I?
SPIEGEL: But probably the worst moment caused by his phonagnosia happened when Royster was a little bit older.
Mr. ROYSTER: Someone called me on the phone, and I was trying to be what I thought was flirtatious with the woman I was then married to, and it was the wrong woman.
SPIEGEL: Since that conversation, Royster has suggested that people identify themselves upfront.
Alix Spiegel, NPR News, Washington.
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