About

Jeffrey Mielke is a professor in the Department of English at NC State University, with a background in linguistics. He received his PhD in linguistics from Ohio State University in 2004, working with Elizabeth Hume. His research focuses on phonetics and phonology, particularly the development and spread of sound change, individual differences in phonological representations, and articulatory analysis using ultrasound imaging. Mielke has conducted extensive projects on phonetic factors influencing sound change in Canadian French, investigating how pronunciation norms evolve and spread among speakers. He also explores the role of individual differences, including those related to Autism Spectrum Disorders, in phonological variation. As director of the NC State Phonetics Laboratory and an active contributor to the field, he has authored a book on distinctive features and numerous journal articles on phonetic and phonological topics. His work combines acoustic analysis, articulatory imaging, and perception studies to deepen understanding of speech variation and change.

Research topics

• Psychology
• Medicine
• Computer Science
• Speech recognition
• Orthodontics
• Mathematics
• Audiology
• Anatomy
• Linguistics

Selected publications

• Impacts of jaw surgery on speech in Class III patients

  Nature Communications · 2026-04-28

  articleOpen access

  Patients with severe Dentofacial Disharmony such as Class III underbites have a twentyfold increased prevalence of speech disorders. To understand the longitudinal effects of corrective jaw surgery on speech, a prospective observational cohort study was conducted of Class III patients (n = 67, Ages 15-36, without clefts). Class I proportional controls (n = 54) and Class III patients were recorded 1-2 months pre-surgery, 2-6 months post-surgery (short-term) and 9-14 months post-surgery (long-term). Speech recordings were evaluated through distortion ratings and measurement of spectral changes in consonant production. ANOVAs and linear mixed-effects models were used to assess changes in speech and cephalometric measures. Here we show that spectral features, distortion, self-reported speech outcomes, and cephalometric measures significantly improve post-operatively. Patients with severe distortions improve the most after surgery. Consonant production requires properly positioned articulatory structures, and surgery provides longitudinal speech improvement for patients with jaw disproportions. Data indicate functional benefit of jaw surgery on speech.

  PublisherDOI

• Automatic classification of stop realisation with wav2vec2.0

  2025-08-17

  articleOpen access

  Modern phonetic research regularly makes use of automatic tools for the annotation of speech data, however few tools exist for the annotation of many variable phonetic phenomena. At the same time, pre-trained self-supervised models, such as wav2vec2.0, have been shown to perform well at speech classification tasks and latently encode fine-grained phonetic information. We demonstrate that wav2vec2.0 models can be trained to automatically classify stop burst presence with high accuracy in both English and Japanese, robust across both finely-curated and unprepared speech corpora. Patterns of variability in stop realisation are replicated with the automatic annotations, and closely follow those of manual annotations. These results demonstrate the potential of pre-trained speech models as tools for the automatic annotation and processing of speech corpus data, enabling researchers to 'scale-up' the scope of phonetic research with relative ease.

  PublisherOA PDFDOI

• /t d/ Releases are strengthening among White speakers: Evidence from a large-scale acoustic study of English in Raleigh

  Language Variation and Change · 2025-03-01

  articleOpen accessSenior author

  Abstract The release and aspiration of word-final /t/ and /d/ are important sociolinguistic variables in American English because they have strong, contextually driven indexicality. Word-final /t d/ releases are usually coded impressionistically due to the absence of automated methods for identifying prepausal release bursts or aspiration. This paper introduces an automated method for identifying released tokens prepausally and for measuring phonetic properties of releases. We use the method to code prepausal /t d/ release versus non-release in a corpus of conversational English in Raleigh. We assess the data in relation to internal and social factors in order to validate the automated method, finding that the patterns in the automatically generated distributions match those in previous studies. We next show that among Raleigh White speakers but not Black speakers, /t d/ releases are becoming more frequent and stronger after obstruents across apparent time, a change that reflects Raleigh’s changing cultural landscape.

  PublisherOA PDFDOI

• A Lingual Ultrasound Study of Speech in Patients With Cleft Lip and Palate Following Orthognathic Surgery

  Orthodontics and Craniofacial Research · 2025-04-11

  articleOpen access

  OBJECTIVES: This study evaluated the effects of orthognathic surgery on speech of Class III ('underbite') patients with repaired cleft lip and palate (CLP) through ultrasound imaging, aerodynamic assessment and articulatory analyses before and after surgery to evaluate how surgery impacts articulation, velopharyngeal (VP) function and hypernasality. MATERIALS AND METHODS: Tongue gestures of five Class III patients with repaired CLP, five Class III patients without CLP and five Class I controls were visualised through ultrasound imaging pre- and post-surgery. Tongue Dorsum Excursion Index and Tongue Constraint Position Index (TCPI) were calculated using ultrasound, and VP insufficiency (VPI) indices were measured using pressure flow assessment and compared with qualitative-perceptual ratings by Speech-Language Pathologists (SLPs). Linear mixed-effects models were used to test for significant post-operative changes in Dorsum Excursion Index and TCPI among consonants. Pressure flow measures are expected to estimate VP gap size during speech using PERCI-SARS. RESULTS: Patients with CLP had significantly lower Dorsum Excursion Index for /k/ before front (p = 0.001) and back vowels (p < 0.001). TCPI revealed consistently lower values for patients with CLP than controls and Class III patients, with inter- and intra-speaker variation for all consonants. Pressure flow data of two patients with CLP showed evidence of VPI and altered nasality post-surgery. CONCLUSION: Patients with CLP present with lower Dorsum Excursion Index and TCPI when compared to controls, suggesting more anterior tongue positioning. Dorsum Excursion Index and TCPI can be used to understand tongue shape and movement changes, potentially elucidating functional effects of jaw surgery on speech. Dorsum Excursion Index and pressure flow data indicate increased compensatory articulations and VPI after orthognathic surgery for patients with CLP, impacting speech.

  PublisherOA PDFDOI

• Automatic classification of stop realisation with wav2vec2.0

  ArXiv.org · 2025-05-29

  preprintOpen access

  Modern phonetic research regularly makes use of automatic tools for the annotation of speech data, however few tools exist for the annotation of many variable phonetic phenomena. At the same time, pre-trained self-supervised models, such as wav2vec2.0, have been shown to perform well at speech classification tasks and latently encode fine-grained phonetic information. We demonstrate that wav2vec2.0 models can be trained to automatically classify stop burst presence with high accuracy in both English and Japanese, robust across both finely-curated and unprepared speech corpora. Patterns of variability in stop realisation are replicated with the automatic annotations, and closely follow those of manual annotations. These results demonstrate the potential of pre-trained speech models as tools for the automatic annotation and processing of speech corpus data, enabling researchers to 'scale-up' the scope of phonetic research with relative ease.

  PublisherOA PDFDOI

• Exploring the anatomy of articulation rate in spontaneous English speech: relationships between utterance length effects and social factors

  2024-09-01 · 1 citations

  articleOpen access

  Code and Data for "Exploring the anatomy of articulation rate in spontaneous English speech: relationships between utterance length effects and social factors", accepted for presentation at Interspeech 2024, Kos, Greece, 1-5th September.

  PublisherOA PDFDOI

• Distinctive Features

  Elsevier eBooks · 2024-01-01

  book-chapter1st authorCorresponding
  PublisherDOI

• Regional vowel patterns as shown by discrete cosine transforms

  The Journal of the Acoustical Society of America · 2024-03-01

  article

  This project presents a new approach to analyzing geographical patterning in vowel variation that combines discrete cosine transforms (DCTs) with cluster analysis. It offers a means of reducing bias from analyses of geographical patterning in vowel variation. DCT0 and DCT1 capture the overall position of vowels in the vowel envelope and DCT2 adds information about curvature. To mitigate anomalies, these metrics are based on numerous tokens and measurement points. Cluster analysis can then be applied to the DCT data to indicate which speakers are most similar without predetermined groupings. The procedure suggests how vowel realizations are correlated with geographical divisions, if at all, within the area covered by a dialect survey. Here, we apply DCTs and hierarchical clustering to a corpus of speakers born 1970 or later and covering eastern Ohio, West Virginia, and western North Carolina. The results align only partially with isophones from earlier dialect surveys. Analyses of individual vowel phonemes typically exhibit considerable intermixture of forms; clearer geographic patterns emerge primarily when multiple vowels in named chain shifts are considered together. Recent dialect leveling appears to play a role in the paucity of distinguishable regional patterns.

  PublisherDOI

• Multitaper Spectrum Analysis of Consonants Produced by Patients With Dentofacial Disharmonies

  Journal of Speech Language and Hearing Research · 2024-01-31 · 2 citations

  articleOpen access

  PURPOSE: This study investigates differences in American English consonants produced by patients who present with various dentofacial disharmonies (DFDs), including severe overbites (Class II), underbites (Class III), and anterior open bites. Previous studies have found that patients with these malocclusion types all produce lingual sibilants and plosives with increased spectral center of gravity and increased spectral variance relative to controls. This result is puzzling since some DFD groups differ from controls in opposite ways, and it is also difficult to interpret because spectral moment measures are affected by a wide range of speech and nonspeech factors. METHOD: To better understand the articulatory basis of these differences, we apply articulatorily interpretable spectral measures derived from multitaper spectra. RESULTS: We find that all groups of DFD patients produce /s ʃ t tʃ/ with midfrequency spectral peaks that are less prominent than those of the control group, but peak frequency measures are largely the same across all groups. CONCLUSION: We conclude that the DFD patients differ more in sibilant noise source properties than in front cavity filter properties.

  PublisherDOI

• Exploring the anatomy of articulation rate in spontaneous English speech: relationships between utterance length effects and social factors

  arXiv (Cornell University) · 2024-08-13

  preprintOpen access

  Speech rate has been shown to vary across social categories such as gender, age, and dialect, while also being conditioned by properties of speech planning. The effect of utterance length, where speech rate is faster and less variable for longer utterances, has also been shown to reduce the role of social factors once it has been accounted for, leaving unclear the relationship between social factors and speech production in conditioning speech rate. Through modelling of speech rate across 13 English speech corpora, it is found that utterance length has the largest effect on speech rate, though this effect itself varies little across corpora and speakers. While age and gender also modulate speech rate, their effects are much smaller in magnitude. These findings suggest utterance length effects may be conditioned by articulatory and perceptual constraints, and that social influences on speech rate should be interpreted in the broader context of how speech rate variation is structured.

  PublisherOA PDFDOI

Recent grants

• Phonetic and Phonological Documentation of Kalasha, an endangered Indo-Aryan language

  NSF · $323k · 2016–2021

• Speech Across Dialects of English (SPADE): large-scale digital analysis of a spoken language across space and time

  NSF · $200k · 2017–2022

• Phonological implications of covert articulatory variation

  NSF · $377k · 2015–2021

Frequent coauthors

• Jane Stuart‐Smith

  17 shared

• Morgan Sonderegger

  17 shared

• Erik R. Thomas

  Ono Pharmaceutical (United States)

  12 shared

• Rachel Macdonald

  12 shared

• Diana Archangeli

  University of Arizona

  11 shared

• Laura Anne Jacox

  10 shared

• Vanna Willerton

  10 shared

• Qandeel Hussain

  University of Toronto

  10 shared

Labs

• Research and EngagementPI

Awards & honors

• Grand Awards Judge (Behavioral and Social Sciences), Intel I…