The Impact of Formal Musical Training on Speech Comprehension in Heavily Distracting Environments

Alexandra Bruder – alexandra.l.bruder@vanderbilt.edu

Vanderbilt University Medical Center, Department of Anesthesiology, 1211 21st Avenue South, Medical Arts Building, Suite 422, Nashville, TN, 37212, United States

Joseph Schlesinger – joseph.j.schlesinger@vumc.org
Twitter: @DrJazz615

Vanderbilt University Medical Center
Nashville, TN 37205
United States

Clayton D Rothwell – crothwell@infoscitex.com<
Infoscitex Corporation, a DCS Company
Dayton, OH, 45431
United States

Popular version of 1pMU4-The Impact of Formal Musical Training on Speech Intelligibility Performance – Implications for Music Pedagogy in High-Consequence Industries, presented at the 183rd ASA Meeting.

Imagine being a waiter… everyone in the restaurant is speaking, music is playing, and co-workers are trying to get your attention, causing you to miss the customer’s order. Communication is necessary but can be hindered due to distractions in many environments, especially in high-risk environments, such as aviation, nuclear power, and healthcare, where miscommunication is a frequent contributing factor to accidents and loss of life. In domains where multitasking is necessary and timely and accurate responses must be ensured, does formal music training help performance?

We used an audio-visual task to test if formal music training can be useful in multitasking environments. Twenty-five students from Vanderbilt University participated in the study and were separated into groups based on their level of formal music training: no formal music training, 1-3 years, 3-5 years, and 5+ years of formal music training. Participants were given three tasks to attend to, a speech comprehension task (modeling distracted communication), a complex visual distraction task (modeling a clinical patient monitor), and an easy visual distraction task (modeling an alarm monitoring task). These tasks were completed in the presence of a combination of alarms and/or background noise and with/without background music.

formal musical training study Image courtesy of Bruder et al. original paper. (Psychology of Music).

Our research focused on results regarding the audio comprehension task and showed that the group with the most formal music training did not show changes in response rate with or without background music added, while all the other groups did. Meaning that with enough music training, background music is not a factor influencing participant response! Additionally, the number of times the participants responded to the audio task depended on the degree of formal music training. Participants with no formal music training had the highest response rate, followed by the 1-3-year group, then the 3–5-year group, with the 5+ year group having the lowest response rate. However, all participants were similar in accuracy overall, and accuracy decreased for all groups when background music was playing. Given the similar accuracy among groups, but less frequent responding with more formal music training, it appears that formal music training helps inform participants to not respond when they don’t know the answer.

Image courtesy of Bruder et al. original paper (Psychology of Music).

Why does this matter? There are many situations when responding and getting something wrong can be more detrimental than not responding, especially in time pressure situations where mistakes are costly to correct. Although the accuracy was similar between all groups, the groups with some formal music training seemed to respond with overconfidence, but did not know enough to increase accuracy, resulting in a potentially dangerous situation. This is contrasted with the 5+ formal music training group, who showed no effect of background music on response rate and who used their trained ears to better judge the extent of their understanding of the information and were less eager to respond to a difficult task under distraction. It turns out that those middle school band lessons paid off after all, that is, if you work in a distracting, multitasking environment.

A moth’s ear inspires directional passive acoustic structures

Lara Díaz-García – lara.diaz-garcia@strath.ac.uk
Twitter: @laradigar23
Instagram: @laradigar

Centre for Ultrasonic Engineering, University of Strathclyde, Glasgow, Lanarkshire, G1 1RD, United Kingdom

Popular version of 2aSA1-Directional passive acoustic structures inspired by the ear of Achroia grisella, presented at the 183rd ASA Meeting.

Read the article in Proceedings of Meetings on Acoustics

When most people think of microphones, they think of the ones singers use or you would find in a karaoke machine, but they might not realize that much smaller microphones are all around us. Current smartphones have about three or four microphones that are small. The miniaturization of microphones is therefore a desire in technological development. These microphones are strategically placed to achieve directionality. Directionality means that the microphone’s goal is to discard undesirable noise coming from directions other than the speaker’s as well as to detect and transmit the sound signal. For hearing implant users this functionality is also desirable. Ideally, you want to be able to tell what direction a sound is coming from, as people with unimpaired hearing do.

But dealing with small size and directionality presents problems. People with unimpaired hearing can tell where sound is coming from by comparing the input received by each of our ears, conveniently sitting on opposite sides of our heads and therefore receiving sounds at slightly different times and with different intensities. The brain can do the math and compute what direction sound must be coming from. The problem is that, to use this trick, you need two microphones that are separated so the time of arrival and difference in intensity are not negligible, and that goes against microphone miniaturization. What to do if you want a small but directional microphone, then?

When looking for inspiration for novel solutions, scientists often look to nature, where energy efficiency and simple designs are prioritized in evolution. Insects are one such example that faces the challenge of directional hearing at small scales. The researchers have chosen to look at the lesser wax moth (fig 1), observed to have directional hearing in the 1980s. The males produce a mating call that the females can track even when one of their ears is pierced. This implies that, instead of using both ears as humans do, these moths’ directional hearing is achieved with just one ear.

Lesser wax moth specimen with scale bar. Image courtesy of Birgit E. Rhode (CC BY 4.0).

The working hypothesis is that directionality must be achieved by the asymmetrical shape and characteristics of the moth’s ear itself. To test this hypothesis, the researchers designed a model that resembles the moth’s ear and checked how it behaved when exposed to sound. The model consists of a thin elliptical membrane with two halves of different thicknesses. For it, they used a readily available commercial 3D printer that allows customization of the design and fabrication of samples in just a few hours. The samples were then placed on a turning surface and the behavior of the membrane in response to sound coming from different directions was investigated (fig 2). It was found that the membrane moves more when sound comes from one direction rather than all the others (fig 3), meaning the structure is therefore passively directional. This means it could inspire a single small directional microphone in the future.

Laboratory setup to turn the sample (in orange, center of the picture) and expose it to sound from the speaker (left of the picture). Researcher’s own picture.
Image adapted from Lara Díaz-García’s original paper. Sounds coming from 0º direction elicit a stronger movement in the membrane than other directions.

Media Invited to Acoustical Society of America Meeting in Nashville, Dec. 5-9

Livestreamed press conferences highlight latest advancements in science of sound #ASA183

Contact:
AIP Media Line
301-209-3090
media@aip.org

NASHVILLE, Tenn., Nov. 10, 2022 – The Acoustical Society of America (ASA) will hold its 183rd meeting Dec. 5-9 at the Grand Hyatt Nashville Hotel. ASA183 will be an in-person meeting with several hybrid sessions where remote attendance will also be possible.

The scientific conference brings together acoustical experts and researchers from around the world to share experiments and applications on topics as diverse as dust devils on Mars, therapeutic music apps, 3D printed violins, and using machine learning to detect diarrhea and prevent cholera outbreaks – just to name a few. Conference highlights can be found on social media by searching the #ASA183 hashtag.

Reporters are invited to attend the meeting at no cost (registration details below) and participate in a series of press conferences featuring a selection of newsworthy sessions. Reporters may also register to join the press conferences virtually. Times and topics will be announced in the coming weeks, and journalists may pre-register here: https://live.webcastplatform.com/go/asa.

——————— SAMPLING OF INTERESTING SESSIONS ——————–

  • 1pMU6 – Emotion equalization app: A first study and results.
  • 2aSA4 – Old meets new: 3-D printing and the art of violinmaking
  • 3aPAa6 – Automated detection of dust-devil-induced pressure signatures
  • 5aAB2 – Vocal learning, chorusing seal pups, and the evolution of rhythm.
  • 3pAA1 – Modern movie sound: reality and simulated reality.
  • 1pCA9 – The feces thesis: Using machine learning to detect diarrhea.
  • 1pCA8 – Pneumonia diagnosis algorithm based on room impulse responses using cough sounds
  • 2aAAa7 – Noise from above: A summary of studies regarding the perceived annoyance due to impact sounds

More information on these and all other meeting sessions is available via ASA’s meeting page and in the technical program:
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eppro02.ativ.me/web/planner.php?id=ASAFALL22&proof=true

———————– MORE MEETING INFORMATION ———————–
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eppro02.ativ.me/web/planner.php?id=ASAFALL22&proof=true

ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are 300 to 500 word summaries of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org.  For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

The safe noise level to prevent hearing loss is probably lower than you think

Daniel Fink – djfink01@aol.com
Twitter: @QuietCoalition

Board Chair, The Quiet Coalition, 60 Thoreau Street Suite 261, Concord, MA, 01742, United States

The Quiet Coalition is a program of Quiet Communities, Inc.

Popular version of 3pNS1-What is the safe noise level to prevent noise-induced hearing loss?, presented at the 183rd ASA Meeting.

Ear structures including outer, middle, and inner ear. Image courtesy of CDC

If something sounds loud, it’s too loud, and your auditory health is at risk. Why? The safe noise exposure level to protect your hearing- to prevent noise-induced hearing loss (NIHL) and other auditory disorders like tinnitus, also known as ringing in the ears, might be lower than you think. Noise damages delicate structures in the inner ear (cochlea). These include minuscule hair cells that actually perceive sound waves, transmitted from the air to the ear drum, then from bones to the fluid in the cochlea.

Figure 1. Normal hair cells (left) and hair cells damaged by noise (right). Image courtesy of CDC

[A little detail about sound and its measurement. Sound is defined as vibrations that travel through the air and can be heard when they reach the ear. The terms sound and noise are used interchangeably, although noise usually has a connation of being unpleasant or unwanted. Sound is measured in decibels. The decibel scale is logarithmic, meaning that an increase in sound or noise levels from 50 to 60 decibels (dB) indicates a 10-times increase in sound energy, not just a 20% increase as might be thought. A-weighting (dBA) is often used to adjust unweighted sound measurement to reflect the frequencies heard in human speech. This is used in occupational safety because the inability to understand speech after workplace noise exposure is the compensable industrial injury.]

Many audiologists still use the industrial-strength 85 dB noise level as the level at which auditory damage begins. This is incorrect. The 85 dBA noise level is the National Institute for Occupational Safety and Health (NIOSH) recommended occupational noise exposure level (REL). This does not protect all exposed workers from hearing loss. It is certainly not a safe noise level for the public. Because of the logarithmic decibel scale, 85 decibel sound has approximately 30 times more sound energy than the Environmental Protection Agency’s 70 decibel safe sound level, not about 20% as might be thought.

The EPA adjusted the NIOSH REL for additional exposure time- 24 hours a day instead of only 8 hours at work, 365 days a year instead of 240 days- to calculate that 70 dB average noise exposure for a day would prevent noise-induced hearing loss. This is the only evidence-based safe noise level I have been able to find.

But the real safe noise level to prevent NIHL must be lower than 70 dB. Why? EPA used the 40-year occupational exposure in its calculations. It didn’t adjust for lifetime exposure (approaching 80 years in the United States before the COVID pandemic). NIHL comes from cumulative noise exposure. This probably explains why so many older people have trouble hearing, the same way additional years of sun exposure explains the pigmentation changes and wrinkles in older people.

My paper explains that the NIOSH REL, from which EPA calculated the safe noise level, was based on studies of workers using limited frequency audiometry (hearing tests), only up to 4000 or 6000 Hertz (cycles per second). More sensitive tests of hearing, such as extended-range audiometry up to 20,000 Hertz, shows auditory damage in people with normal hearing on standard audiometry. Tests of speech in noise- how well someone can hear when background noise is added to the hearing test- also show problems understanding speech, even if standard audiometry is normal.

The actual noise level to prevent hearing loss may be as low as 55 dBA. This is the noise level needed for the human ear to recover from noise-induced temporary threshold shift, the muffling of sound one has after exposure to loud noise. If you’ve ever attended a rock concert or NASCAR race and found your hearing muffled the next morning, that’s what I’m talking about. (By the way, there is no such thing as temporary hearing loss. The muffling of sound, or temporary ringing in the ears after loud noise exposure, indicates that permanent auditory damage has occurred.)

55 dB is pretty quiet and would be difficult to achieve in everyday life in a modern industrialized society, where average daily noise exposures are near 75 dB. But I hope that if people know the real safe noise level to prevent hearing loss, they will avoid loud noise or use hearing protection if they can’t.

The FAA allows Americans to be exposed to unsafe levels of aircraft noise

Daniel Fink – djfink01@aol.com
Twitter: @QuietCoalition

Board Chair, The Quiet Coalition, 60 Thoreau Street, Concord, MA, 01742, United States

The Quiet Coalition is a program of Quiet Communities, Inc., Lincoln, MA, USA

Popular version of 4aNS8-The Federal Aviation Administration (FAA) allows Americans to be exposed to unsafe levels of aviation noise

Presented at the 183rd ASA Meeting

Photo credit: Pixabay 

The American Public Health Association states, “Noise is unwanted and/or harmful sound.” Noise not loud enough to damage hearing causes high blood pressure, heart attacks, and strokes. The Federal Aviation Administration (FAA) considers noise an annoyance but does not acknowledge the adverse health effects of aircraft noise. Based on the Schultz curve, the FAA adopted 65 dBA Day-Night Level (DNL) as “the threshold for significant aviation noise, below which residential land use is compatible.”  The FAA’s recent Neighborhood Environmental Survey found that many more Americans are annoyed by noise than previously known.

Schultz Curve and Neighborhood Environmental Survey results, showing that many more Americans are annoyed by noise than the Schultz Curve showed. Source: FAA

Schultz Curve and Neighborhood Environmental Survey results, showing that many more Americans are annoyed by noise than the Schultz Curve showed. Source: FAA

[I have to tell you a little about the science of sound or noise measurement. The words sound and noise are used interchangeably. Sound is measured in decibels (dB). The decibel scale is logarithmic. This means that a 10 dB increase from 50 to 60 dB indicates 10 times more sound energy, not merely 20% more. Because noise disrupts sleep, DNL measures noise for 24 hours but adds a 10 dB penalty for noise between 10 p.m. and 7 a.m.  A-weighting (dBA) adjusts sound measurements for the frequencies heard in human speech. A-weighting is not the right measure for aircraft noise because aircraft noise has lower frequencies than speech. A-weighting also reduces unweighted sound measurements by about 20-30 dB.]

According to the Environmental Protection Agency (EPA), though, safe noise levels are only 45 dB DNL for indoor noise and 55 dB DNL for outdoor noise. The World Health Organization (WHO) recommends lower aircraft noise levels: 45 dB Day-Evening-Night Level (adding a 5 dB penalty for noise between 7-10 p.m.) and 40 dB at night.  Both EPA safe noise levels and WHO recommended aircraft noise levels are obviously much lower than the FAA’s 65 dBA DNL, especially because they use unweighted dB.

Being annoyed or disturbed by aircraft noise is stressful.  Stress increases heart rate and blood pressure. Stress increases blood levels of stress hormones.  Stress causes inflammation of the blood vessel lining. in turn causing cardiovascular disease, including hypertension and heart attacks, and other adverse health effects. Scientific experts think that the evidence is strong enough to establish causality, not merely a statistical association. Epidemiological studies demonstrating these effects have been confirmed by human and animal research. The biological mechanisms are now understood at the cellular, subcellular, molecular, and genetic levels.  Aircraft noise also affects poor and minority communities more than others. Children are also more sensitive to damage from noise, which also interferes with learning.

The FAA insists that more research is needed, but no more research is needed to know that aviation noise is hazardous to health.  The FAA must establish lower noise standards to protect Americans exposed to aircraft noise.