How does SMR compare to AMR in diadochokinetic tasks for AOS?

• A. SMR is typically more challenging than AMR due to sequencing demands.
• B. AMR is more challenging than SMR due to repetition of sounds.
• C. Both are equally challenging.
• D. Neither AMR nor SMR is affected in AOS.

Answer: (B)

In diadochokinetic tasks for apraxia of speech, the key difference is sequencing versus repetition. SMR requires rapid transitions between different articulatory targets (for example, pa-ta-ka), which heavily taxes motor planning and the ability to sequence movements. Those sequencing demands tend to produce more errors and slower rates in AOS, especially at the transitions between sounds. AMR, on the other hand, involves repeating the same syllable quickly (pa-pa-pa), which relies more on executing a single gesture and is typically less affected by the sequencing problems characteristic of AOS. So, SMR is usually more challenging than AMR in individuals with AOS.