Lip Reading and the use of visual clues

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Lip reading or more accurately speech reading, since it includes facial gesture and body language, is a great help to the hearing impaired in making sense of speech. Lip reading is not sufficient on its own but together with the additional visual information available, even with impaired hearing, speech is much easier to understand.

Most of us lip-read to some extent in difficult listening situations and this can be a most useful adjunct to hearing aid use. Even with normal hearing a person will look at a speaker whenever possible to assist the communication process. In noisy surroundings, there may be some reliance on mouth movements and facial expressions to increase understanding. Many hearing impaired people acquire great skill without any conscious effort, while others may benefit from lip-reading classes.

Such classes also bring together people with similar problems, which may also be very helpful in an individual’s adjustment to hearing loss.

Many speech sounds cannot be differentiated by the visual pattern alone. Groups of phonemes that look the same when spoken are known as ‘visemes’ *(visemic-visually distinctive) E.g. `p’, `b’ and `m’ are part of the same viseme group, a speech reader could only conclude that one of the group had been spoken.Is is thought that only about 50% of a spoken message can be understood through lip reading alone. Lip- reading classes provides activities to aid development of speech reading. Even when significantly reduced hearing is coupled with speech reading, the listener’s ability to comprehend may be greatly increased.

Lip-reading classes are usually provided through the local education authority. With impaired hearing, there is likely to be some dependence on visual clues. Visual information may through observing visual cues (speech reading) or through a manual communication system (signing or finger spelling). The degree of dependence is related to the degree of hearing impairment. Someone who is profoundly deaf is reliant on visual information, whereas with a mild hearing loss hearing remains a primary communication channel.