Given that speech errors in Childhood Apraxia of Speech arise from miscoordination of the timing among multiple articulatory gestures, a common sign of this disorder is ...

• A. better accuracy during imitation than during spontaneous picture naming.
• B. difficulty imitating oral movements such as touching the tongue tip to the side of the mouth.
• C. an unusually slow rate of speech, especially when repeating single syllables, [papapa...].
• D. single feature substitution errors such as oral/nasal and voiced/voiceless confusions.

Answer: (D)

The underlying issue in Childhood Apraxia of Speech is that the timing of multiple articulatory gestures must be coordinated precisely to make fluent speech. When this timing coordination breaks down, the resulting errors often reflect the motor system’s planning at the level of phonetic features. That leads to substitutions that affect a single feature, such as changing an oral sound to a nasal (oral vs nasal) or altering voicing (voiced vs voiceless). These single-feature substitutions arise because the child’s motor plan cannot smoothly sequence the gestures needed for the target sound, so the produced sound settles on a nearby, easier-to-plan option in terms of a single feature. While other signs—like groping, slow repetition, or differences between imitation and spontaneous speech—can occur, the distinctive timing-based miscoordination tends to manifest as these minimal, feature-level substitutions, making them a common sign of CAS.