Abstract
It is well-established that seeing the face of a speaker can substantially improve speech perception, especially under adverse listening conditions. However, previous studies have demonstrated that this audiovisual benefit is highly variable across individuals and measurement indices (Grant & Seitz, 1998; Tye-Murray et al., 2016). Here we present a planned study designed to quantify the audiovisual benefit for acoustically degraded English single phonemes, words and sentences in the general, healthy population alongside pilot data testing audiovisual perception of phonemes and words (N=7, data collection ongoing) and re-analyses of existing behavioural data of audiovisual sentences (N=14). Rather than comparing changes in intelligibility due to adding visual speech (which is prone to floor and ceiling effects) we measure the relative intelligibility of matched audiovisual (AV) and auditory-only (AO) speech. Our study will add to the existing literature by establishing the distribution of audiovisual speech perception skills and benefit in the general population.