One of the most difficult situations in which to hear well is to hear one person in a group of loud-spoken people. Not hearing well in the company of friends and family is a quality of life issue. Without the ability to hear what is going on, you tend to withdraw and become isolated. Rather than giving up on social interaction, I recommend that you try a pair of hearing aids. Hearing aids are outfitted with directional microphones to help you focus in a direction you choose. For instance, if you are driving a car and want to hear the passenger more clearly, you can push a button to stream the sound from the passenger side into the opposite ear hearing aid. The aids are able to turn down the noise from the window and receive the speech from the passenger so that you hear them in both ears equally. It really helps increase the clarity of the speech. Some of the hearing aids are able to do this without pushing a button. The aids have sensors (a computer program) that know when you are in a car environment and automatically make the adjustment for you!
What happens when you are in a restaurant? The hearing aids are able to reduce distant sound from a nearby table so that you are better able to focus on the person sitting across the table from you. To do this, the hearing aids turn down the input from the back facing microphone. This will provide a better signal-to-noise ratio. In this case, the signal is the person across the table and the noise is the group of people behind you. Research has shown us that people with hearing loss need more of a reduction in noise compared to speech (signal to noise ratio) than people with normal hearing. That is why normal hearing people are able to understand speech in moderate noise. The brain and auditory pathways are able to separate the two signals better if you have normal hearing and processing. The problem arises if you have compromised hearing organs (cochlea) or compromised pathways into the area of the brain that understands speech. The current hearing aids are not able to eliminate the unwanted noise, but they are able to reduce the noise.
Researchers at Columbia University are focusing on this issue by combining traditional hearing aid technology with brain scanning and artificial intelligence. It is called auditory attention decoding (ADD), or a cognitively controlled hearing aid. In the research stage, they use externally worn sensors that monitor brain activity to determine what the hearing target is, and then it isolates the targeted speech and makes it louder while suppressing all the background noise. (That is a lot to put into one sentence, much less into one hearing aid!) To collect the massive amount of data coming from the brain, the person wears a cap with electrodes in it so that the electrodes touch the scalp. The information is fed to a computer that is able to learn what you prefer to hear and what you want to ignore. This system can take a single audio channel from a group of speakers (talking people) and combine it with the listener’s neural signals (from the brain) and in less than 10 seconds it determines which speaker is being listened to and amplifies it to the required loudness for clarity. One day you will be able to have cognitively controlled hearing aids!
Until the time that these hearing aids are available to the public, we need to continue to use the following tips to get the most out of what we can hear.
- Ask people to face you when they speak.
- Reduce background noise when possible.
- Select off times to go out to restaurants so they are not so noisy.
- Ask people to get your attention before they start speaking.
- Ask people to speak slower, not louder.
- Keep the hearing aids and ear canals clean.
- Have the hearing aids checked once a year for proper function.
By following these guidelines, you will have more success understanding speech in a competitive environment. If you are not happy with the sound of your hearing aids even when you are at home, then maybe it is time to investigate the newer technology that is available. A one month trial of the newer technology while you own your older hearing aids is a great way to make an apples-to-apples comparison. QCBN
By Karon Lynn, Au.D.