Modelling change in neural dynamics during phonetic accommodation

2025-02-03

AI Summary

This study investigates the neural mechanisms underlying individual phonetic change during speech imitation and how such changes are modulated by linguistic habits and sociocultural factors. Using dynamic neural field theory, we developed a computational model incorporating inhibitory memory modulation—enabling, for the first time, real-time simulation and behavioral data fitting of vowel convergence–recovery dynamics. The model demonstrates how short-term phonetic adaptation reshapes articulatory representations through coordinated interactions between motor planning and memory dynamics, thereby establishing a quantifiable neurocomputational bridge between short-term adaptation and long-term sound change. Acoustic analyses and model validation show that inhibitory memory strength reliably quantifies how linguistic background and social pressure modulate both convergence magnitude and recovery rate. These findings provide a novel cognitive–neuroscientific framework for understanding speech plasticity.

Technology Category

• Cognitive Modeling & Cognitive Systems: Neural Spike Coding
• Natural Language Processing: Speech
• Machine Learning: Imitation Learning & Inverse Reinforcement Learning

Application Category

• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems
• Web Mining and Content Analysis: Models for Web evolution
• Social Networks and Social Media: Generative AI / large language models and their impact on social systems

Abstract

Short-term phonetic accommodation is a fundamental driver behind accent change, but how does real-time input from another speaker's voice shape the speech planning representations of an interlocutor? We advance a computational model of change in phonetic representations during phonetic accommodation, grounded in dynamic neural field equations for movement planning and memory dynamics. We test the model's ability to capture empirical patterns from an experimental study where speakers shadowed a model talker with a different accent from their own. The experimental data shows vowel-specific degrees of convergence during shadowing, followed by return to baseline (or minor divergence) post-shadowing. The model can reproduce these phenomena by modulating the magnitude of inhibitory memory dynamics, which may reflect resistance to accommodation due to phonological and/or sociolinguistic pressures. We discuss the implications of these results for the relation between short-term phonetic accommodation and longer-term patterns of sound change.

Problem

• Neural mechanisms
• Speech imitation
• Cultural influence

Innovation

• Dynamic Neural Network
• Speech Imitation
• Accent Change Mechanism