Understanding Hard of Hearing vs Deaf

These terms, 'hard of hearing' and 'deaf,' are often used to describe individuals who experience varying degrees of hearing loss. However, there is a significant difference between the two conditions, one that extends beyond a simple definition of deafness.

Hearing Impairment: A Quantitative Measure

Both 'hard of hearing' and 'deaf' imply that the hearing is not 'normal,' meaning that the hearing is not as good as what the majority of the population can hear at a young age. However, these terms are more colloquial and do not provide precise definitions. Doctors and audiologists prefer to describe hearing loss quantitatively, as hearing thresholds can worsen over time due to various factors such as aging, disease, or environmental noise. This article aims to clarify the differences between 'hard of hearing' and 'deaf' by exploring the quantitative aspects of hearing loss.

The Normal Hearing Range

Hearing thresholds can vary widely, and hearing loss can be classified into different categories based on the threshold levels. For instance, a hearing level of around 35 dB HL at all frequencies from 250 through 8 K is considered a 'mild loss.' Although this degree of hearing loss can make it challenging to understand speech, it does not typically fit the clinical definition of 'deaf.' In this case, the individual may choose to have the TV louder, look at the speaker when they are talking, or struggle in noisy environments. In such situations, 'hearing impaired' might be a more accurate description, but it is not often used.

Severe Hearing Loss and Deafness

On the other hand, hearing thresholds above 80 to 100 dB at higher frequencies can be indicative of more severe hearing loss, often associated with aging or other hearing impairments. Individuals with such high-frequency loss often struggle to understand speech without assistance. Their hearing loss is more pronounced, and they may benefit from the use of hearing aids, which can selectively amplify sound in the frequencies where the hearing thresholds are poorest.

Audiometric Profiles

The following sections present audiograms to illustrate the differences between 'hard of hearing' and individuals who are 'deaf.' Audograms are graphical representations of hearing thresholds at different frequencies, often plotted on a hearing test.

Mild Hearing Loss (hard of hearing)

Consider the following audiogram for someone with a mild hearing loss:

The audiogram shows the hearing thresholds in the right ear, marked by red circles, and the left ear, marked by blue X's, at about 35 dB HL at all the frequencies from 250 through 8 K. While this degree of hearing loss can present challenges, it is not typically described as 'deaf.'

Severe Hearing Loss (deaf)

Now consider the audiogram for someone with a more severe hearing loss, marked by the X and O between 80 and 100 dB, which are typical of aging or other hearing impairments:

This individual's hearing loss in the high frequencies is more pronounced, making it challenging to understand speech without assistance. They may need to request others to repeat what they say, play the TV louder, or complain to their spouse that the speaker is not talking clearly. In such cases, they are likely to benefit from hearing aids, and they may describe themselves as 'hard of hearing' but would rarely describe themselves as 'deaf.'

Understanding Speech and Hearing Perception

Understanding speech involves receiving and interpreting auditory signals, primarily within the range of 250 to 8000 cycles per second (Hz). The human ear and auditory system perceive these signals differently at different frequencies. Normal hearing is characterized by a consistent threshold of perception across these frequencies. However, individuals with hearing impairments, such as those with severe high-frequency loss, may have a different threshold of perception, which can make it challenging to understand speech without assistance.

Conclusion

While both 'hard of hearing' and 'deaf' describe hearing impairments, the terms are used to convey different levels of severity. 'Hard of hearing' typically refers to a milder form of hearing loss, where individuals may experience some difficulty in understanding speech but are not typically considered 'deaf.' On the other hand, 'deaf' often implies a more significant loss of hearing, making it difficult to comprehend auditory signals and speech. Understanding the quantitative aspects of hearing loss can help individuals and healthcare providers better assess and address hearing impairments.