TELEVISION CAPTIONS FOR HEARING-IMPAIRED PEOPLE - A STUDY OF KEY FACTORS THAT AFFECT READING PERFORMANCE

Closed captions are broadcast with television programs for special-nee ds viewers such as hearing-impaired people. We examined how caption pr esentation rate, small amounts of induced dioptric blur, and English l earned as a second language affect the reading performance of good rea ders. Thirty-two college graduates with normal hearing and vision, hal f of whom learned English as a second language, read television captio ns that consisted of white capital letters equivalent in size to 20/92 Snellen letters on a black background. Text was presented at rates of 55, 120, and 216 words/min. Lenses of 0, 0.5, 1.0, or 1.5 diopters (D ) were worn over the person's best refractive correction. The fastest text rate and small amounts of blur significantly disrupted reading pe rformance. People who learned English as a second language were hinder ed more by presentation rate than by dioptric blur. Surprisingly, peop le with refractive errors (even though they were optically corrected) were hindered less by induced blur than were people with normally clea r vision.