What is the difference between intelligibility and articulatory accuracy in AOS assessment?

• A. Intelligibility refers to the speed of speech; articulatory accuracy is about grammar.
• B. Articulatory accuracy refers to the correctness of individual sounds; intelligibility reflects how well listeners understand overall speech.
• C. Intelligibility is the same as articulatory accuracy.
• D. Articulatory accuracy includes prosody; intelligibility excludes it.

Answer: (C)

In AOS assessment, the focus is on two related but distinct aspects of speech: how precisely sounds are produced and how much of the spoken message a listener can understand. Articulatory accuracy is about the correctness of individual sounds—whether each phoneme is produced with the right place, manner, voicing, and sequence. Intelligibility, however, is about the listener’s ability to understand the overall message in natural speech, which depends not only on sound accuracy but also on rate, rhythm, prosody, coarticulation, and context. They are related, but not the same: you can have good articulation for many sounds and still have lower intelligibility if prosody or pacing disrupts comprehension, and you might have some articulation errors yet be largely understood because the meaning is clear from context.