Page 50 - Spring 2006

Acoustics in the news
AARP Bulletin. The interactive software program, called LACE (Listening and Communication Enhancement) train- ing, runs on a personal computer. It feeds the brain exercises that include rapid speech as well as sentences spoken in noisy situations and against a competing voice. The exercises help users with skills critical to communication, like listening, attention and focus.
􏰀 Musical training can help the brain process the spoken word, according to a story in the November 17 San Francisco Chronicle. Musical experience helps the brain improve its ability to distinguish between rapidly changing sounds that are key to understanding and using language. Children, who aren’t good at rapid auditory processing and are at high-risk for becoming poor readers may especially benefit from musi- cal training. What is promising about the study, researchers believe, is the notion that the brain isn’t an immutable organ fixed at birth but is adaptable and people can change their mental agility.
􏰀 Conductors of bands and orchestras are much better at localizing sound sources than non-musicians, according to a story in the November 22 issue of The New York Times. The study, whose results were reported at a conference of the Society for Neuroscience, is part of an examination of the way in which auditory and visual information is integrated in the brains of highly trained musicians.
􏰀 The “updates” page in the December issue of United’s inflight magazine Hemispheres briefly describes noise-can- celing headphones and noise-isolating earphones. In the for- mer, microphones sample the acoustic environment and try to generate a sound that will cancel low- and midrange-fre- quency background noise. Noise-isolating earphones, on the other hand, try to shut out as much ambient sound as possi- ble by making an air-tight fit in the ear canal. They are most effective for high-frequency noise.
􏰀 Forbes.com posted a note, dated December 1, about how cochlear implants work, that attempts to explain why implants restore hearing for some, but not for others. The main bottleneck is a structure called the “endbulb of Held,” which contains a large number of synapses where signals pass from one auditory nerve cell to another. In congenitally deaf cats cochlear implants worked when endbulb synapses received electrical signals for three months. The study sug- gests that there is a window with congenital deafness that shuts just before puberty.
􏰀 A new advanced combat helmet allows soldiers to better localize sounds, according to a story on KGO-TV (San Francisco, Oakland, and San Jose) based on a Discoveries and Breakthroughs in Science tape produced by AIP. The new helmet, designed by acousticians, sits away from the ear, which allows more sound to enter the ear in a direct path. Tests on this and several other helmets were described in paper 4pPP3 at the 149th ASA meeting in Vancouver.
􏰀 A very thoughtful editorial “Poor acoustics can hinder learning” appears in the December 8 issue of the Kingsport (TN) Times-News. “Levels of noise that do not interfere with
perception of speech in adults may interfere significantly with the perception of speech by children.” The author, a clinical audiologist who also writes regularly for the Times-News, mentions that the ASA and other organizations helped to develop standards for classroom acoustics in 2002.
􏰀 “The Real Death of Print” is the title of a news feature in the 1 December issue of Nature. “Despite clashes with publishers over copyright,” the story says, “Google’s plan to make mil- lions of books available online is turning the tide for efforts to digitize the world’s literature. The move to digitize books is set to transform the worlds of publishers, librarians, authors, readers and researchers. The president of the American Library Association says he is not worried that libraries could become obsolete. As well as providing access to books, they serve as a place for people to meet and study, he says. The director of e-books for a major publisher thinks the future of reading lies in small electronic devices from whose screens people will read books wherever they are. Having a mixture of e-books and print books could be the answer.
􏰀 In an effort to understand bird calls, scientists at the University of Alberta have recorded and analyzed the sounds of black-capped chickadees, according to a story in the December 24 issue of the Toronto Star. “Songbirds learn their vocalization from caregivers, just like people,” the researchers say. “They’re potentially a good model for human speech and perception.” The next step in the research is to test how good human volunteers are at distinguishing avian chirping and then to start looking at how humans perceive animal vocal- ization.
􏰀 A simple sonic device that can continuously monitor the concentration of gas emitted by bacteria has been developed at Penn State University according to a story in the December 26 issue of the Pittsburgh Post-Gazette. The device includes a small loudspeaker and a pair of microphones that determines the resonance frequency of a tube; changes in gas composi- tion cause changes in the speed of sound. One application of the device is to monitor microbial fuel cells in which bacteria digest organic matter in wastewater to produce hydrogen to power the cells.
􏰀 An artist and a doctor are hoping to make a new map of the “sonic body” by revealing its sounds, from veins to organs and muscles, according to a news report on BBC News, December 27. The noises they record using sensitive medical equipment from stethoscopes to scanners will then be made into an interactive art installation triggered by visitors walking through a model of a body. People will need to walk around the installation to trigger the sounds.
􏰀 Few high school cheerleaders have won awards at interna- tional science fairs and appeared on national television, but Courtney Rafes of Justin, Texas has, according to a story in the December 23 issue of the Dallas Morning News. Courtney’s entry in the 2005 Intel International Science and Engineering Fair won an honorable mention from ASA (see “We hear that...” in this issue) and also brought her offers of a $20,000 scholarship and an internship with the Department
48 Acoustics Today, April 2006