The effects of age upon the visual perception of speech.

A sample of 110 middle-aged and geriatric subjects (40 to 87 years) with normal hearing and vision was drawn from the general population in order to compare visual performance for consonant-vowel (CV) syllables and sentences. Results of this investigation revealed that, above 70, age was a factor affecting visual perception of syllables. Individuals above age 70 received the poorest speechreading scores and were inconsistent in viseme categorization. Results of a comparison of speechreading scores for sentences and syllables revealed a greater number of differences among sentences. Only individuals between 40 and 60 years of age received statistically similar mean scores when presented with common sentences. Finally, using a linear regression model, it was found that sentence speechreading performance could be accurately predicted from the CV syllable score within a range of accuracy of +/- 9.7%.