Phonetic differences between affirmative and feedback head nods in German Sign Language (DGS): A pose estimation...

Area of Science:

• Linguistics
• Computer Vision
• Conversational Analysis

Background:

• Head nods vary in form across spoken and sign languages.
• Previous research often lacked naturalistic data and ignored addressee head nods.
• The form-function relationship of head nods in sign language remains unclear.

Purpose of the Study:

• To investigate phonetic variations in head nods based on their communicative function in German Sign Language (DGS).
• To test the hypothesis that affirmation and feedback head nods differ in form and co-occurrence with manual cues.
• To analyze the role of non-manual cues in the turn-taking system of sign languages.

Main Methods:

• Utilized OpenPose, a computer vision toolkit, for automated extraction of head nod measurements from video recordings.
• Analyzed head nods in natural dyadic German Sign Language (DGS) interaction data.
• Examined phonetic properties including duration, amplitude, and velocity, and their interaction with manual items.

Main Results:

• Phonetic properties of head nods significantly differ between affirmative and feedback functions.
• Feedback nods are generally slower and smaller in amplitude compared to affirmation nods.
• Feedback nods frequently occur without simultaneous manual gestures, unlike affirmation nods.

Conclusions:

• Head nod variations are linked to their distinct roles in conversational turn-taking.
• Non-manual cues, like head nods, are crucial for the structure of sign language turn-taking.
• This research integrates sign language linguistics, conversational analysis, and computer vision.