Measurement of articulation functions using adaptive test procedures

The conventional methods for measuring speech intelligibility/discrimination present entire lists of words at constant levels whereas an adaptive procedure shifts levels within a single list according to a preselected strategy. The results reported in this paper indicate that adaptive testing of monosyllabic speech communication : 1) provides reasonably stable and accurate results with a CNC (words with a consonant-vowel-consonant structure) test vocabulary of 50 words; 2) permits an efficient description of selected points on the rising portion of an articulation function; and 3) gives the tester a number of flexible testing options such as choice of strategies and preselection of target scores. In addition, the potential exists for estimation of measurement errors both within and between test sessions, with these estimates based on either group or individual test responses.