Oral Motor Abilities Are Task Dependent: A Factor Analytic Approach to Performance Rate.

Area of Science:

• Neurology
• Speech-Language Pathology
• Motor Control

Background:

• Performance rates of speech and non-speech oral motor tasks are often used to assess articulation rate abnormalities in neurologic movement disorders.
• The relationship between speech rate and non-speech oral motor task rates is not fully understood.

Purpose of the Study:

• To investigate the structural relationship between rate measures of speech and distinct oral motor behaviors.
• To determine if speech and non-speech oral motor tasks measure the same or separate underlying constructs.

Main Methods:

• Factor analysis was employed to analyze rate data from 130 patients with neurologic movement disorders and 130 healthy controls.
• Data included oral reading (speech), rapid syllable repetition (speech-like), and rapid single articulator movements (nonspeech).

Main Results:

• A measurement model indicated that different task types loaded onto separate latent variables.
• Speech tasks and oral motor tasks, including rapid syllable repetition and repetitive single articulator movements, measure distinct traits.

Conclusions:

• Speech performance rates and oral motor task rates represent separate constructs.
• Clinical inferences about articulation rate abnormalities should consider the distinct nature of these task types.