Is understanding speech in noise and over distance a challenge HCPs should address for all, or only some of their patients? Fitting data offers insights into who can benefit from microphone technology.
As human beings, many of us connect with others and create relationships through listening and verbal communication. We use communication to gain knowledge, perform work tasks, and to socialize. However, the presence of background noise, distance and reverberation make it challenging to communicate, even for those with normal hearing, but the effect is quite significant for those with hearing loss.
There are a number of factors that affect speech intelligibility, including room geometry, reverberation time, distance away from the speaker, background noise level, and severity of hearing loss. The closer you are to the source of the sound, the louder the sound is perceived. For every doubling in distance away from the sound source, the intensity decreases by 6 dB SPL and is perceived to be softer. This is also true in free field environments. Sound spreads out and becomes weaker as the energy thins.
Increasing the volume isn’t the answer
The more favorable the signal-to-noise ratio (SNR), the more intelligible the spoken message. SNR is approximately +6 dB for individuals with normal hearing. This level is even greater for those with hearing loss (up to +20 dB). Now, imagine a frustrating scenario for a hearing aid wearer trying to understand speech in a restaurant where noise can reach peak levels of 80 dB (A). The listener’s reaction may be to increase the volume of their hearing aid in order to improve the audibility of the speech. Unfortunately, what also happens is that amplification of the noise occurs at the same time. While the listener perceives the speech as being louder, the noise is also proportionately louder and intelligibility has not been improved.
Modern hearing aids and cochlear implants have improved over the years in providing greater benefit in hearing and speech understanding. However, there are still some limitations when used alone. In fact, MarkeTrak 9 survey showed 31 percent of hearing aid wearers reported listening challenges in background noise, even while wearing hearing aids.1 Additionally, a study performed in 2016, illustrated a reduction in speech intelligibility from 52 percent at 1.5 meters to 13 percent at 4.5 meters with hearing aids.2 Therefore, hearing aids and cochlear implants alone are sometimes not enough.
Roger designed specifically to overcome hearing challenges
To combat hearing challenges in noise and over distance, assistive listening technologies, such as wireless microphones, can be combined with hearing aids and/or cochlear implants. Roger™, a digital adaptive multi-channel microphone technology, wirelessly transmits a speaker’s voice directly to a hearing aid or cochlear implant sound processor via a Roger receiver. It is designed specifically to improve speech understanding in noise and over distance.
However, is Roger a solution for everyone? It has been previously assumed that Roger is for those with severe to profound hearing loss to improve their speech understanding. To understand the profiles of the end-users being fitted with Roger and to determine if this assumption stands true, data collection was performed using CUPeR data from Phonak Target fitting software. The sample consisted of 698 end-users from the United States, Belgium, Austria and Israel. The end-user profiles included age of the end-user, hearing loss severity, and hearing aid performance level.
CUPeR data sheds light on who benefits
The data showed that Roger is fit across all ages, from infancy to 90+ years, with approximately 54 percent of working age. Furthermore, Roger is fitted across all severities of hearing losses, with the greatest percentage (38 percent) at moderate hearing loss. When considering hearing aid performance level and Roger, CUPeR data highlighted that Roger is combined mostly with premium and advanced level hearing aid technology, approximately 80 percent of the time. This suggests that regardless of age and hearing loss severity, end-users who invest in premium and advanced technology levels are more likely to want the complete hearing solution package to obtain the best advantage in improving speech understanding.
The highlighted results proved our previous assumption to be incorrect. Roger technology is not just for those with severe to profound hearing losses. And, even the most advanced hearing aids have limitations when worn alone when in background noise and at a distance. A Roger microphone is needed to improve intelligibility of the sound source in these challenging situations. CUPeR data also illustrates that regardless of age and hearing loss severity, the Roger system is a beneficial solution to bridge this gap.
1 Abrams, H. & Kihm, J. (2015). An introduction to MarkeTrak IX—A new baseline for the hearing aid market. Hearing Review 22: 16.
2 Selesho, E. & Zwarts, G. (2016). Improved speech recognition in meetings with the Roger Table Mic™. Phonak Field Study News. Retrieved from http://FSN_Roger_improved_speech_recognition_210x297_GB_V1.00.pdf