AMR and SMR in AOS assessment: which statement is true?

• A. AMR assesses speed; SMR tests planning and sequencing.
• B. AMR assesses speed; SMR assesses planning and sequencing.
• C. SMR assesses planning and sequencing; AMR assesses strength.
• D. Neither AMR nor SMR are used.

Answer: (C)

The main idea is that AMR and SMR measure different demands on motor speech programming. AMR (alternating motion rate) looks at how quickly and smoothly the lips, tongue, and jaw can repeat a single sound or syllable in succession. This is a measure of speed and fluency of repeating movements. SMR (sequential motion rate), on the other hand, requires rapid transitions between different articulators in a sequence (for example, moving from one syllable to another in a deliberate pattern). That task places a higher load on planning and sequencing of movements.

In practice, AMR is described as assessing speed, while SMR assesses planning and sequencing. This distinction helps explain why SMR tends to be more sensitive to apraxia of speech, which involves difficulties in planning and sequencing motor movements, whereas AMR mainly reflects the speed of basic articulator movements.

So the statement that best captures this is that AMR measures speed and SMR measures planning and sequencing. The notion that AMR tests strength or that neither test is used isn’t accurate, since these tasks are specifically designed to probe speed and sequencing, not strength, and both measures are used in AOS assessments.