NEW YORK (CNNMoney.com) -
Think you might get a kick out of having Mr. T. or Dennis Hopper give you driving directions? Several companies are rolling out celebrity voice systems that work with standard navigation systems. But making the wrong choice could be dangerous, according to an expert on computer voices.
While we change the ringtones on our cell phones all the time, our cell phones aren't interacting with us as we drive.
"Voices are incredibly powerful, much more so than ringtones." said Clifford Nass, author of the book "Wired for Speech" and a professor at Stanford University who studies human/computer speech interaction.
Even though we all realize that a car's navigation system is a computer, our brain still responds to anything speaking to us as if it were a person.
If we're feeling annoyed and our car is speaking to us in a chipper voice, we get more annoyed, said Nass.
Worse, said Nass, are voices that are overtly distracting. (Think of Mr. T barking at you to turn left). You know that it's just a computer, but, emotionally, you will still react.
Will Andre, chief executive officer of NavTones, the company that produces the Mr. T car navigation voice, said he feels the voice is no more distracting than a cell phone conversation and has the benefit of getting drivers to attend to the directions.
The best voices for cars, said Nass, are those that match the driver's mood and personality. Extroverted people trust computers that sound outgoing. Introverted people like computers that sound a little shy, like they are.
There are a lot of issues to consider.
If the voice coming out of our car's navigation system lacks sufficient authority, we might not trust it. In experiments, said Nass, drivers didn't feel comfortable when a car navigation system had the voice of an elderly person. That was true even of older drivers.
Emotions, which can change from moment to moment, are harder to match but computers can certainly sound happy, sad, excited or bored. The problem is gauging the driver's emotions so that the computer can respond appropriately, but that's something that is being worked on at automotive communication labs at Stanford, Nass said.
One general rule is that people like voices that sound more or less like themselves and voices that, we feel, are consistent with the role they're playing, said Nass. The wrong voice can be unnerving and distracting, he said.
"Most accents have stereotypes, good or bad, with them," he said. "From a societal point of view this leads to a very big problem."
The voices that come out of our computer guides could help break down some of those stereotypes. Instead, they usually tend to reinforce them by speaking to us in the "voice of authority" we already expect and trust. In the United States that means that , almost always, your car's voice is that of a white midwestern man or woman, said Nass.
Allowing users to install voices of their own choosing could mean that other types of voices will finally get some time in the virtual driver's seat.
Turn left in 500 feet... fool!