Mapping the Speech Code: Cortical Responses Linking the Perception and Production of Vowels

Area of Science:

• Cognitive Neuroscience
• Speech Science
• Auditory Perception

Background:

• The relationship between speech production and perception is a key area of debate in linguistics and neuroscience.
• Listeners' utilization of speech production experience for perception is not fully understood.
• Electrophysiological responses offer insights into the timing of perceptual changes.

Purpose of the Study:

• To investigate how sensorimotor adaptation in speech production affects speech perception.
• To examine the electrophysiological correlates of this production-perception link.
• To determine if early or late cortical responses are more sensitive to production-induced perceptual shifts.

Main Methods:

• Participants engaged in baseline and post-training speech production tasks with altered auditory feedback for one group.
• Vowel categorization tasks were performed before and after the production training.
• Electroencephalography (EEG) was used to record brain activity during perception tasks.

Main Results:

• No significant group differences in phonetic categorization were found.
• Exploratory analyses revealed correlations between vocal motor behavior and phonetic categorization.
• EEG data showed correlations between vocal motor behavior and cortical responses in both early and late time windows.

Conclusions:

• Recent speech production behavior influences subsequent vowel perception.
• The observed perceptual changes can be characterized as an "acoustics-to-articulation" mapping.
• Sensorimotor adaptation in speech production has measurable effects on auditory perception.