The effect of speechreading on the speech-reception threshold of sentences in noise.

The monaural speech-reception threshold of sentences in noise, here defined as the 50% correct-syllables threshold, was measured for a female speaker with and without speechreading via a video monitor. The additional visual information resulted in a 4.6-dB lower threshold for a group of 12 young subjects and in a 4.0-dB lower threshold for a group of 18 elderly subjects compared to auditory presentation alone.