Middle ear muscle activity during vocalization in normal speakers and stutterers

Area of Science:

• Neuroscience
• Auditory Physiology
• Speech Science

Background:

• Middle ear muscles are known to contract before vocalization.
• The specific muscle responsible for this pre-vocalization activity remains unidentified.
• Conflicting reports exist regarding differences in this activity between stutterers and normal speakers.

Purpose of the Study:

• To identify the primary middle ear muscle involved in pre-vocalization activity.
• To investigate potential differences in pre-vocalization muscle activity between stutterers and normal speakers.

Main Methods:

• Utilized extratympanic pressure measurements to assess middle ear muscle activity before vocalization.
• Differentiated activity from the stapedius and tensor tympani muscles.
• Compared pre-vocalization pressure changes with muscle-specific tasks.

Main Results:

• Pre-vocalization activity in both normal speakers and stutterers predominantly resembles tensor tympani muscle activation.
• The temporal course of this activity was accurately tracked.
• No significant differences were found in the time course of pre-vocalization activity between stutterers and normal speakers.

Conclusions:

• The tensor tympani muscle is primarily responsible for the pre-vocalization acoustic reflex.
• There are no discernible differences in tensor tympani pre-vocalization activity between stutterers and normal speakers.
• Findings contradict previous reports suggesting group-specific differences.