US Hearing Health, Better Telephone Speech

Newswise — Which US population groups have the best and worst hearing, according to a new study? Do whales use their sonar as an x-ray system to identify their dinner? How have researchers improved cell-phone sound quality without changing the existing telecommunications infrastructure? What amazing ultrasound trick did scientists employ to perform what may be the first noninvasive delivery of a medical compound into a specific region of a living brain? These questions will all be answered in a web pressroom and a press luncheon for the Acoustical Society of America (ASA) meeting in Providence, RI.

The luncheon will be held on Tuesday, June 6 from 11:30 a.m.-1:15 p.m. in the Blackstone Room of The Westin Providence (One West Exchange St, Providence, RI). The speakers and topics are listed below. The entire acoustics meeting takes place from June 5-9, 2006.

The following text describes the press luncheon topics, and lists some examples of lay language papers that are available online.

PRESS LUNCHEON TOPICSAcoustical Society of America MeetingBlackstone Room, Westin Providence HotelOne West Exchange St, Providence, RITuesday, June 6, 200611:30 a.m. - 1:15 p.m.

1. Better-Sounding Phone Speech with "Bandwidth Extension"Presenter: Harsha M. Sathyendra, University of Florida. Ever wonder why it's hard to tell the difference between words like "sailed" and "failed" on the telephone? It's because phones only transmit a limited range of audio frequencies (between 300-3400 Hz), rather than the 50-8000 Hz range that contains most speech content. Employing a method called bandwidth extension (BWE), Harsha M. Sathyendra , in collaboration with Ismail Uysal, both from the University of Florida, will demonstrate a technique for restoring relevant information to the missing low and high frequencies. Working with existing telecommunications infrastructure, this technique has the potential of improving both mobile-phone and landline audio in the future. (Paper 3aSC5)

2. Whale Bubble Nets and Trumpet Sounds for Identifying and Catching Herring.Orest Diachok, Johns Hopkins Applied Physics Laboratory , Laurel, MDIn the Gulf of Alaska, humpback whales work in groups to capture herring, with one whale broadcasting sound at a herring school to drive them to the water surface. A second whale blows a "net" of bubbles to encircle the rising school. As Orest Diachok of the Johns Hopkins University Applied Physics Laboratory in Laurel, MD reports, during this process one or more of the whales emits long "trumpet" tones at several different frequencies, one of which resonates with, and is attenuated (absorbed) by the swim bladders of the herring (analogous to x-rays being absorbed by water in human lungs). Diachok proposes that the whales might use this phenomenon to infer the fish length, species, and size of school. (Paper 4aAO5)

3. Noninvasively Delivering Molecules to Specific Brain RegionsPresenter: Elisa Konofagou, Columbia UniversityThe Blood Brain Barrier (BBB) prevents pathogens in the bloodstream from entering the brain, but it also prevents the admission of potentially helpful drugs. Researchers in recent years have discovered that ultrasound can temporarily open up the BBB. Injecting microbubbles into mice and applying ultrasound transcranially (through intact skin and skull), a Columbia University group (Elisa Konofagou and James Choi) has demonstrated that it is possible to send gadolinium, an FDA-approved contrast agent used for medical imaging, directly and noninvasively into a part of the mouse brain known as the hippocampus. These results demonstrate the very promising feasibility of using ultrasound to noninvasively deliver drugs to specific parts of the brain. (Paper 1aBB11)

4. New Data on Hearing HealthPresenter: William Murphy, National Institute for Occupational Safety and Health, Cincinnati, OHInvestigating the hearing levels of today's adults and comparing the data to those collected 35 years ago, Murphy will report the results of the National Health and Nutrition Examination Survey (NHANES), which tested a nationally representative sample of over 5000 individuals in the US population from 1999-2004. The median hearing levels of persons aged 20-69 have changed little from the NHANES conducted from 1971-1975, which examined adults who were 25-74 years of age. In addition, the recent NHANES indicate that, as a function of ethnicity, non-Hispanic blacks have the best hearing and non-Hispanic whites have the poorest hearing thresholds, particularly among males and in the older age groups. (Paper 2aPPb5)