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CHAPTER THREE Mapping Your Own Audiogram Kris English, Ph.D. Understanding how to read your own audiogram will assist you in better understanding your personal hearing challenges. At first, this might seem complicated, but it really is quite easy and straightforward. In my discussion with you, I will present “Mini-Summaries” of each section, provided throughout to review vocabulary and concepts, and occasionally “Audiogram Alerts” are provided to highlight a particular point of concern. In time, you will be an expert in describing your audiogram. So let’s work together in this exploration. An audiogram has three main components: 1. A range of pitches, from low to high. 2. A measurement of loudness, from soft to very loud. 3. Your hearing levels for each pitch for each ear. Audiogram Components Audiogram Component #1: Pitch The first component of the audiogram is the range of pitches presented in the hearing test. Wearing headphones (or maybe insert earphones), you heard a series of beeps that may have reminded you of notes on a piano. Some had very low pitches (like the deep bass notes on the left end of the piano keys), some were very high pitches (similar to the far right end of piano keys), and some were in between. These pitches are lined up on the horizontal part of the audiogram, as shown in Figure 3-1. Another term used to describe these beeps is “pure tones.” You may have noticed each beep was like a single note on a piano, with no chords or harmonics. The human ear can hear pure tones much lower and higher than the ones shown on the audiogram, but it would take too much time to test them all. For efficiency’s sake we focus on what people are most interested in hearing—human speech. So the pure tones found in human speech are selected for testing and are the ones reported on your audiogram. It may seem a little strange to say these pure tones have anything to do with human speech, but when analyzed electronically, each speech sound has been found to be a unique and complex combination of these pure tones. That’s why your hearing care professional started with pure tone testing, as a way to describe the “building blocks” of your hearing ability. Chances are, the term “frequency” was used during an explanation of your hearing test. For example, you may have been told you have a “high frequency hearing loss.” Frequency means pitch: a way of expressing the number of cycles per second (cps) a sound wave occurs in one second. A sound that vibrates your eardrum at 500 times per second (cps) is perceived by our brain as having a low pitch, like the hum of the motor in your refrigerator. As the vibrations per second increase, the pitch of the sound will seem higher and higher, like the cheep of a bird. . . |
