Page 38 - April 2008

Fig. 2. Ranking, writing comments, and psychoacoustic evaluation.
activities over areas and in time. Sounds are processed differ- ently by people in diverse cultures and different meanings and evaluations can be given to the “same” acoustical event depending on living situations.
The question whether there is any significant influence on animals through environmental noise was brought up with respect to psychoacoustic measurements by Klaus Genuit and Andre Fiebig. In contrast to Schulte-Fortkamp and Dubois, who prioritized the meaning of noise, they highlighted rele- vance, determination, and interpretation of psychoacoustics and other hearing related parameters “in the context of envi- ronmental noise, with respect to hearing sensation of humans.” The question of whether ani-
mals undergo similar psy-
choacoustic processes was
debated at the end of their
talk. Finding techniques to
make these measurements
represents an important chal-
lenge of animal research.
David C. Waddington and his coworkers described a practical application of these ideas, describing the assess- ment of residential low fre- quency noise complaints. They collected field measure- ments of both noise and citi- zen complaints and described results that included a consid- erable “top down” influence of subject attitudes on genera- tion of noise complaints, uncorrelated with the acoustic characteristics of the noise.
Overview papers on ani- mals showed the importance of improving technological as well as theoretical approaches to studying the effects of noise
on wildlife. Due to differences in the psychoacoustic capabili- ties and ecology of the many species of concern, a wide range of approaches and metrics have been applied over the past twenty years to determine effects on animals, making studies somewhat difficult to compare and progress slow (Robert Kull). Issues and outcomes of experimental studies of noise impact on wildlife suggested that much of this research has been overly focused on short-term, high-amplitude exposures. More sophisticated models of effect need to be developed, with emphasis on mechanisms of injury, which are rarely docu- mented in animals, and long-term, cumulative impact of expo- sure to multiple sources (A. Bowles and coworkers).
Fig. 4. Psychoacoustic analysis.
Fig. 3. Measuring people’s minds; talking to the new experts.
36 Acoustics Today, April 2008