# Cluster analysis of articulatory trajectories in fluent nonword productions separates adults who stutter from fluent speakers

## TL;DR

This study shows that fluent-sounding speech in people who stutter has different articulatory movement patterns compared to fluent speakers.

## Contribution

It introduces a method using cluster analysis of articulatory trajectories to distinguish between adults who stutter and fluent speakers.

## Key findings

- Clustering of articulatory trajectories successfully separated 80% of stuttering and fluent speakers.
- Fluent-sounding utterances from people who stutter show distinct movement patterns compared to controls.
- Real-time MRI data revealed differences in articulation during pseudoword production.

## Abstract

Whether fluent-sounding utterances of adults who stutter are normally articulated is unclear. We asked 15 patients and 17 matched controls to utter a pseudoword while recording real-time MRI at 55 frames per second in a midsagittal plane, and we automatically clustered participants for distances between sites of articulation. Clustering was successful in 80% of the cases, indicating major differences in the movement patterns of fluent sounding utterances in both groups.

The online version contains supplementary material available at 10.1038/s41598-025-25829-0.