When a hearing specialist (an audiologist) tests hearing, typically he/she measures the decibel level at which an individual hears a pure tone at a given frequency. These decibel levels may then be graphed to form an audiogram. Averaging the decibel levels across different frequencies yields a pure tone average. For example, the average decibel levels at 500, 1000, and 2000 Herz (Hz) gives a speech frequency pure tone average (SFPTA). The average decibel levels at 1000, 2000, and 4000 Hz gives the high frequency pure tone average (HFPTA). These pure tone averages may then be used to determine whether someone might benefit from an amplification device, like a hearing aid. Just like visual acuity is only one aspect of vision, pure tone audiometry is only one measure of hearing ability. For example, other measures of hearing include speech understanding, speech reception thresholds, and bone conduction.
Pass out the worksheets “Charting Audiograms” and “Audiogram Graph” to each student. Have them graph the audiometric data from “Charting Audiograms” on the "Audiogram Graph." Use a circle as a symbol for the decibel levels from the right ear and a triangle for the decibel levels from the left ear. Plot the data from the younger and older person on the same graph. The older person's pattern is characteristic of ‘presbycusis' and shows a high frequency loss at the higher decibel levels. Have the students discuss the differences between the younger and older person's audiograms.
Graph, audiogram, presbycusis, speech frequency, frequency, tone