HHTM Hearing News Round-up: Notable Stories This Week

November 14, 2018

Before you deep fry that turkey or candy those yams, take a few minutes to catch up on some noteworthy news items of professional interest.


New Study Suggests Sparse Real-World Differences Between Basic and Premium Technology


A new peer reviewed study, published-ahead-of-print at Ear and Hearing suggests older adults with mild-to-moderate hearing loss are unlikely to experience real-world benefits of advanced hearing aid technology relative to basic technology.

Yu-Hsiang Wu and collaborators at the University of Iowa compared basic-level hearing aid technology to more expensive premium-level hearing aid technology in a group of 54 older adults with mild-to-moderate hearing loss. Table 1 from the article shows some of the key differences between the two different hearing aids technology levels.

Table 1. Wu, et al, Ear and Hearing, 2018


Each of the study participants wore a pair of hearing aids for series of five-week trials under four conditions:

  1. Basic-level technology, noise reduction features off,
  2. Basic-level technology, noise reduction features on,
  3. Premium-level technology, noise reduction features off, and
  4. Premium-level technology, noise reduction features on. 

Study participants were blinded to the level of technology they were wearing, and all fittings were conducted using a scientifically-validated prescriptive method. These four conditions used the same two commercially available hearing aids, released in 2013.

According to the authors, the suggested retail price of the basic-level device is $1500 per pair, while the premium device has a suggested retail value of approximately $5000 per pair. Both models were from the same manufacturer and shared the same hardware and signal processing chip.

At the end of each five-week trial a series of lab-based and self-report outcomes were collected, including speech-in-noise intelligibility testing at various noise levels and speech locations in the soundbooth, as well as several standardized outcome questionnaires such as the SSQ and APHAB.

Additionally, the study collected real-time in-situ self-report measures while the participants wore the devices throughout the day. The in-situ self-reports were gathered using a smartphone-based ecological momentary assessment system, which is believed to provide a more valid assessment of real world outcomes compared to traditional retrospective self-reports completed in the clinic.

Laboratory data collected in the soundbooth, where listening conditions are well-controlled and carefully regulated by researchers or clinicians, indicated premium-level noise reduction features outperformed basic-level noise reduction features, and noise reduction features turned on outperformed conditions where noise reduction features were turned off. (In the study, noise reduction features are defined as the combination of advanced directional microphones and processed-based digital noise reduction algorithms.)

These laboratory findings, however, did not completely translate to equivalent results in the real world listening conditions of the participants. While data collected from both traditional retrospective self-reports, like the SSQ and APHAB, and from the real-time ecological momentary assessment system indicated participants were more satisfied with noise reduction features on versus noise reduction features off, there wasn’t evidence supporting the benefit of premium-level technology compared to basic-level hearing aid technology.

The findings of this study are like those from researchers at the University of Memphis, who published a series of studies from 2014-2017 that suggested real-world outcomes for basic and premium noise reduction features were similar.

For clinicians, these studies indicate that older adults with symmetrical mild to moderate who seldom communicate in noisy or very noisy listening situations are unlikely to perceive the differences between premium and basic levels of hearing aid technology. (A noteworthy finding of the recent University of Iowa study cited above is that the “typical” older adult spends about 10% of their daily living in noisy or very noisy listening places, perhaps much less time than what many clinicians believe. For consumers, the results of these studies that compare real-world outcomes between technology levels suggest they could save a significant amount of money by opting for a more basic-level of technology, as long as the devices are fitted using clinically-validated methods.

To read the study in its entirety, including its design, clinical implications and limitations, go to the gated site of the American Auditory Society.


The Peer Review Process is Flawed, but it Still Beats the Alternatives


The study mentioned above is a good example of peer reviewed research that is consumed by clinicians and incorporated into the clinical decision-making process. A recent New York Times commentary by Indiana University School of Medicine physician sheds light on the limitations of the peer review process. In his commentary he lists several problems associated with the current peer review process including the biases of those who serve as reviewers. He also provides suggestions for how the peer review process can be improved.

The article can be read here.


Mild Hearing Loss in Younger Adults May Have Long-term Effect on Brain


New research surmises young people with mild hearing loss are putting demands on their brains that typically wouldn’t be seen until later in life. According to the research, subtle forms of hearing loss in young adults– the kind they are probably not even aware of – are exacting a toll on cognitive resources and thus early hearing loss could be paving the way for dementia.

Yung Lee and colleagues at Ohio State University recruited 35 healthy men and women who were 18 to 41 years old and monitored their brain activity while the participants listened to various sentences. According to a report in the Ohio State News, the original study was designed to look just at brain differences when sentence complexity increased – something that is possible with use of functional magnetic resonance imaging (fMRI).

The research team, however, stumbled upon a surprising discovery:  Before the fMRI, the researchers tested participants’ hearing to make sure there weren’t any problems that would interfere with the study. Some of the young people had minor hearing deficits, but nothing serious enough to exclude them from the research.

Consequently, those with minor hearing deficits had fMRI results that took an unexpected turn. Lee and his colleagues were expecting brain activity in the left hemisphere of the brain. But in the subjects with mild hearing loss, the fMRI was showing activity in the right frontal cortex.

Scientists generally believe healthy young people exclusively use the left frontal lobe for language comprehension, and as people age they begin to use more of their right frontal brain to process language. Lee and his colleagues found that many of their study participants with mild (or what they termed subtle) hearing loss had fMRIs that showed right frontal lobe activity – the type of activity you might expect in an adult over the age of 50.  

These findings could indicate that by tapping into the right frontal cortex earlier in life, younger adults with subtle or mild hearing loss could experience a deterioration of hearing comprehension at an earlier than expected age. Thus, what to many younger adults appears to be innocuous habits, like listening to loud music or attending stentorious live concerts, could have irreversible effects later in life. The study can be found here.


The Case of the Shattered Mojito Glass


There has been plenty of speculation about the cause of the now infamous sonic attacks that occurred at the American Embassy in Havana Cuba in 2017. A recent report in the New Yorker speculates that the first sonic attack actually happened nearly 30 years prior. American diplomat, Jay Taylor, recounts a series of unexplained incidents inside the diplomatic residence that began with a mysteriously shattered mojito glass during the Christmas season of 1987. Within a few short days, a glass table top, an ornamental vase and a cup his 3-year-old was drinking out of were all bafflingly shattered.

Perhaps those weird sonic attacks in 2017 are not so new after all. The full report can read at the New Yorker.



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