Improving word understanding, part B
Robert L. Martin · The Hearing Journal · 2011
In January we discussed improving word understanding. This month I want to put the topic in a wider perspective and answer the question, why do some people have major difficulties with word understanding while others with more severe hearing loss have less difficulty? I start this topic by stressing one critical point: Hearing is only part—and sometimes a small part—of the skill set needed for communication. Starting with my grandfather, I have known, worked with, and lived with many people with very poor hearing. My view of the struggle to achieve good word understanding has been strongly influenced by these people, and their stories shaped my view of speech intelligibility. These stories are about Jack, Elaine, Carl, John, and Ann. JACK Jack and Clara owned and operated a successful earmold lab in San Diego many years ago. Jack had a severe-to-profound hearing loss and wore a pair of power-house Siemens BTE hearing aids. Jack was “stone deaf” without hearing aids, according to Clara. His word understanding scores were poor (42% Right and 46% Left at 90 dB HTL); yet when you talked to Jack, you could not tell he had a hearing impairment. Jack was highly social, a happy person. If you estimated his hearing ability by looking at his audiometric test scores, you would be wrong. His audiometric scores said he was close to deaf. His communication ability in the real world was excellent. I remember sitting next to him in a noisy bar. I asked, “Jack can you hear me, can you understand me?” He laughed, “Of course,” he said. “We have been talking for almost an hour. Have I made any mistakes? Is there any part of the conversation I have screwed up?” “But you are almost deaf,” I replied in frustration. “How can you hear in this high-level noise?” He laughed again and said, “You college guys think you know it all. You don't need to hear to be able to hear.” “You sound like Yogi Berra,” I said. “Yeah,” he replied, “and Yogi knows more than you and me put together.” Jack taught me that you don't need to hear to “hear.” On the surface, this story seems impossible, but it's true. The mindset of the patient is critical. Motivation and persistence are the biggest parts of the hearing loss puzzle. Jack chose to live a life like he had normal hearing. He developed all of the skills needed to facilitate quality communication, including staying positive, staying engaged, exuding charm, and being pleasant and polite. ELAINE The professor who taught my first auditory rehabilitation class did not believe lip reading was important. Later, when I was in school at the University of Tennessee, I was assigned a patient named Elaine. She was a phenomenal lip reader and she wanted to know why I did not stress lip reading in her auditory rehabilitation sessions. “I get most of my information by lip reading,” she contended. I disagreed and tried to tell her that most of the information that she was receiving was though her ears, not through her eyes. To prove my point, I put her in a large hearing test suite and gave her words with and without sound (lip-reading cues only and then sound through the earphones with no lip-reading cues). I was astounded by the results. I was wrong and she was right. Her hearing was truly poor and her lip reading ability was incredible. She was receiving more information from lip reading, than hearing. Our “rehabilitation” offices were built into the football stadium overlooking the Speech and Hearing Clinic across the street. One day, I gave Elaine a pair of high-powered binoculars and asked her to lip read the people standing about 150 feet away, outside the clinic. She did so easily. Elaine taught me that lip reading is very valuable. In fact, it is the primary source of information for some people. CARL AND JOHN Carl Asp and John Berry ran an auditory rehabilitation program at the University of Tennessee. There, they used an approach called Verbotonal for their patients, most of whom had severe hearing loss and poor word understanding. One part of their therapy approach used an amplifier system, an elaborate set of filters and high-fidelity earphones to find the patients “best hearing.” They called this zone the Optimal Field of Hearing—the settings that produced the best Word Understanding Scores. They would talk to the patient while adjusting the filters and amplifiers. Most of the time they succeeded in finding settings that facilitated good word understanding. For example, a patient with Word Understanding Scores in the 40s (ex. 46% and 48%) obtained using a standard audiometric testing technique might have Word Understanding Scores in the 80s (ex. 82 and 84%) on the Verbotonal unit. The use of a high-quality microphone, high-tech amplifier, ultra-sophisticated filters, high-quality, high-output earphones, and speaking clearly directly into the microphone, allows many patients who felt they had “very poor” word understanding ability to suddenly understand most of the words. These patients would often get very happy and say things like, “If I could only hear like this with my hearing aids.” There are several crucial parts of the Verbotonal approach (for more information contact Carl or John), but let me stress two: reducing the overall energy in the signal and motivating and supporting the patient. When you use sophisticated filters (low- and high-frequency roll off, notch, and band pass) you markedly reduce the overall power delivered to the ear. You concentrate energy in the most beneficial zones and you avoid the upward spread of masking. Years ago, hearing aids could not duplicate these settings. The multichannel capabilities of the newest hearing aids now allow you to achieve settings similar to these “Optimal Field” settings. Carl and John taught me the value of cleaning up the input signal, delivering crystal clear sound, and reducing the overall output when working with high-powered hearing aid fittings. John taught me the value of being incredibly positive and supportive. Charisma is one of the few forces strong enough to conquer fear—in this case the fear of going deaf. Show patients that, under some circumstances, they can hear well, very well. Then, continuously work with them to find a style of amplification that helps them hear well. John would say, “You have to train the brain to perceive, it is not about hearing, it is all about perception.” Learning to perceive takes work, time, support, love, hope, and motivation. Professional charisma is the magic that makes it all happen. Hearing well is learning. If you moved to Scotland, what would your word understanding score be the first month? How many months (years) would it take before your score reached 100 percent? John taught me the value of being loving, highly dynamic, confident, and secure in your professional knowledge. Thank you John. Hope is powerful medicine. Provide it in unlimited quantities. It works. ANN Ann had normal hearing until the age of three-and-a-half, when she lost her hearing due to ototoxic medications. Her thresholds are about 75–80 dB bilaterally. She was born and raised in China and graduated at the top of all of her classes in the world's most competitive school environment. She learned to speak English without the use of hearing aids and is currently working as a licensed engineer in this country. This is another story that appears impossible on the surface, but again it is true. It is possible to learn another language well with only a little hearing. Ann is proof. Ann taught me that intellect, hard work, and dedication can sometime overcome the huge problems created by hearing loss. THE BIG PICTURE So what does this all mean? First, we do not hear with our ears. We hear with our brains. Second, people with “poor” hearing need to learn to “hear.” They need to learn to use all of the different sources of information: sound, sight, context, and attitude to communicate. Hard-of-hearing people that succeed in doing this have learned to open doors, rather than close them. Third, many of the newer features of amplification, for example, noise reduction, make sound more comfortable, not more clear or easier to understand. Most of the research showing marked improvements in word understanding is, in my opinion, marketing hype. The two exceptions are: a good set of directional microphones that markedly reduce the overall energy package, focusing more energy into the highly useful zone; and the use of just enough compression to avoid the upward spread of masking. People with “poor” hearing need a teacher who is loving, supportive, empathetic, strong, and knowledgeable. Those five words define your job. You might want to add “tenacious” to this list. Never give up.