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Research Uncovers How the Voice Gives Away a Person's Age GAINESVILLE, Fla., Oct. 1 (AScribe Newswire) -- Everyone knows wrinkles and gray hair are visible signs of age. But indicators of age in a person's voice are harder to pin down: For every seeming giveaway such as low volume, it's easy to think of an exception. Now, in findings that could have implications for treatment of speech disorders, criminal forensics and even prove useful in Hollywood, University of Florida scientists think they've cracked at least part of the mystery. Through experiments that hinged on playing recorded voices of people of various ages to listeners and having them guess their ages, UF experts in communication sciences and disorders identified two key elements of speech that seem to signal age: pitch and rate of word delivery. To test their results, they used computer software to manipulate these elements, then played the altered voices for other listeners. The results, to be presented at the Acoustical Society of America annual meeting next month in Austin, Texas, show the scientists consistently made old people sound young - and, to a lesser extent, the young sound old. "The speech signal carries a lot of information," said Rahul Shrivastav, an assistant professor of communications sciences and disorders and the lead investigator on the project. "It carries the meaning of the words, but it also tells you about emotion, identity and age, which is what we're trying to get at with this research." The research has wide applications, Shrivastav said. For example, it may help speech pathologists distinguish age- related speech problems from those related to disease in people suffering from Parkinson's disease. Confirming that a symptom is caused by disease, rather than the normal aging process, would indicate it is potentially curable and thus suggest therapeutic strategies, he said. In the first phase of the study, Shrivastav and his colleagues played to a group of 40 nonexpert listeners the recorded voices of young and old men saying the same sentence. The study focused on men in part because the researchers had more male voices in their database; however, the researchers have since gathered more female voices and will begin testing them soon. From the initial sample, the scientists selected 30 voices participants identified most commonly as those of old or young men, then analyzed them to determine their differences. Although the researchers identified several variables, the most common were speed and pitch. Perhaps predictably, old men speak more slowly than young, some taking twice as long to finish a sentence. Surprisingly, the pitch of old men's voices rise as they age, making their voices sound higher. In the study's second phase, Shrivastav used computer software to speed up and lower the pitch of 13 of the old voices and performed the reverse on 13 younger voices. All repeated the same phrase: "The rainbow is the division of white light into many beautiful colors." A majority of the 65 listeners consistently mistook 12 of the 13 old voices as young. The results were less consistent for the young voices altered to seem old, with a majority of listeners identifying some as old and others not. Shrivastav said the likely cause of the discrepancy was that the scientists didn't go far enough in altering the younger people's voices. "We believe young speakers can indeed be made to sound older," he said. "However, the extent of the manipulation in speed and pitch were not sufficient to result in a significant shift in this research." Richard Morris, associate professor and chairman of communication disorders at Florida State University, called Shrivastav's results "a significant and natural extension of what has previously been reported." "Dr. Shrivastav has taken an important step forward to help our understanding of the changes to speech and voice that occur with age," he said. In addition to providing potential ways to better diagnose and treat speech problems, the research may help therapists treat healthy patients with complaints about their voices. Shrivastav said a colleague recently began treating a 38- year-old woman who complains her voice makes her sound old; the new UF research suggests she try speaking more quickly and lowering her voice. Beyond the medical applications, the scientists say the research also could prove important in helping law enforcement authorities get as much information as possible from crime victims about whether a suspect sounded old or young. And if computer software is developed in the future to "convert" voices from old to young or vice versa in real time, police seeking to catch pedophiles, for example, could "speak" in the voice of typical adolescent girls or boys. Hollywood also may benefit. Just as digital animation and other computer technology has enhanced the portrayal of characters aging decades in movies, so computer software could properly "age" an actor's voice appropriately. Michael Douglas' voice would still be Michael Douglas' voice, just aged 30 or 40 years, depending on the needs of the film, Shrivastav said. SOURCE: AScribe Newswire http://tinyurl.com/pl4p * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn