Understanding speech-in-noise (SIN) is a frequent complaint of the approximately 38 million people in the United States who have a hearing loss. Hearing aid wearers often struggle with SIN too despite the advanced devices in their ears. However, there is an additional 26 million Americans with normal hearing who also complain of hearing difficulty and SIN. People who have a hearing ability that appears normal but still experience hearing difficulty and SIN problems seek out hearing healthcare professionals for help. These individuals are usually told to use better lighting and sit closer to people who are speaking. Unfortunately, these people are probably not being tested any further nor told of tools that could potentially help their problem. The welcome news is that there is help for those who have hearing thresholds within reasonable limits.
What Is Normal?
Defining normal hearing is not easy. Often, the definition of normal hearing is simply the absence of a hearing loss. Numerous scales measure hearing loss and define it differently. The American Speech-Language-Hearing Association (ASHA), defines normal hearing and hearing loss as follows:
- Normal (-15 dB to +15 dB)
- Mild (26-40 dB)
- Moderate (41-55 dB)
- Severe (71-90 dB)
- Profound (91 dB)
Although an individual may have normal hearing according to the scale, they may still experience hearing difficulty and SIN problems. It is essential to administer additional tests for these individuals to seek possible hidden problems.
Possible Causes For The Problem
There are plausible reasons that a person with normal hearing may have trouble with SIN and hearing. Because normal hearing does not warrant the need for additional tests, these conditions are rarely detected. A few of these reasons include:
- A hidden hearing loss and cochlear synaptopathy
- Extended high-frequency hearing loss
- Auditory processing disorders (APD)
- Auditory neuropathy spectrum disorder (ANSD)
Tests For SIN
Because SIN is a complaint among people with normal hearing as well as those without a normal hearing ability, several tests for SIN exist. It is imperative that comprehensive audiometric testing beyond routine testing be available to any patient with normal hearing who complains of hearing difficulty or SIN recognition. Typical tests include:
- Bamford-Kowal-Bench Speech-in-Noise test
- Words-in-noise Test
- Hearing in Noise Test
- BKB-SIN for children
Treating The Problem
Numerous studies demonstrate the benefits of improving the SNR for people with and without hearing problems. Wireless technology helps people understand SIN without the use of cumbersome devices. Hearing aids are a treatment option for people who present with hearing problems, but who have hearing ability within reasonable limits. A remote microphone system can offer many benefits to those who are coping with this condition. These systems can improve cortical auditory-evoked potentials (CAEPs), frequency discrimination, binaural temporal resolution, frequency pattern recognition, and auditory working memory. Other benefits include attention, learning, and behavior improvement. It is crucial for hearing healthcare professionals to offer information, hearing aid trials and speech enhancing technologies to clients who present as normal but claim to have problems hearing and understanding SIN.