Top-down effect of dialogue coherence on perceived speaker identity

Area of Science:

• Cognitive Science
• Psycholinguistics
• Auditory Perception

Background:

• Speaker change detection is crucial for conversational comprehension.
• Two main hypotheses exist: bottom-up acoustic cues versus top-down linguistic processing.
• The role of pragmatic coherence in speaker perception remains under-explored.

Purpose of the Study:

• To experimentally investigate whether pragmatic coherence influences speaker change detection.
• To differentiate between bottom-up acoustic and top-down pragmatic contributions to speaker perception.
• To determine if listeners' expectations about conversational structure affect their judgment of speaker identity.

Main Methods:

• Experiment 1: Participants judged speaker changes in conversation segments with intact pragmatic coherence.
• Experiment 2: Pragmatic information was removed by scrambling word order, while acoustic information was preserved.
• Stimuli were designed so that segments were pragmatically coherent for different speakers, though spoken by the same individual.

Main Results:

• In Experiment 1, listeners incorrectly perceived different speakers when utterances were pragmatically coherent for distinct speakers, despite identical acoustic signals.
• In Experiment 2, removing pragmatic information eliminated this effect; listeners correctly identified the same speaker.
• Results demonstrate a significant top-down influence of pragmatic expectations on speaker change detection.

Conclusions:

• Conversational structure and pragmatic expectations play a critical role in how listeners perceive speaker changes.
• Speaker change detection is not solely reliant on bottom-up acoustic cues.
• Listeners actively use contextual and linguistic information to interpret the unfolding of conversation and identify speakers.