In evaluating AOS, which observation best supports a speech motor planning deficit rather than a pure articulatory weakness?

• A. Slow rate with monotone pitch
• B. Pure vowel elongation
• C. Overall volume reduction
• D. Error patterns and consistency across tasks

Answer: (D)

The key idea is that planning and sequencing the articulatory movements leads to variability in how errors show up across different speaking tasks. In a speech motor planning deficit, a person often produces substitutions, distortions, or omissions that change from word to word and from task to task, and these errors tend to become more frequent with longer, more complex utterances. That inconsistency across tasks points to a problem with selecting and ordering the gestures rather than a pure weakness of the articulators themselves. If the issue were solely articulatory weakness, you’d expect more uniform, predictable errors across various speaking tasks, along with signs like slower rate or reduced loudness but not the trial-to-trial variability tied to planning. The other options describe features like prosodic issues or generalized weak voice quality, which don’t specifically indicate a planning deficit. So, seeing error patterns that vary across tasks best supports a speech motor planning problem.