Research Projects

The general objective of the speech group is to gain an understanding of the processes whereby (1) a speaker transforms a discrete linguistic representation of an utterance into an acoustic signal, and (2) a listener decodes the acoustic signal to retrieve the linguistic representation. The research includes development of models for speech production, speech perception, and lexical access, as well as studies of impaired speech communication.

The following is an outline of the Speech Communication section of the RLE annual report:

  1. Studies of Normal Speech Production
    1. Articulatory Evidence for Acoustic Goals for Consonants: a Pilot Study
    2. Clarity versus Effort in Speech Production: Initial Results of a Pilot Study
    3. Articulatory Processes
    4. Modeling Vocal-fold Vibration
    5. Physiological Modeling of Speech Production
    6. Stop Consonant Production: An Articulation and Acoustic Study
  2. Speech Research Relating to Special Populations
    1. Speech Production of Cochlear Implant Patients
      • Voice Onset Time (VOT)
      • Syllable-to-syllable Regulation of F0 and SPL
    2. Speech Perception by Cochlear Implant Users
      • Development of Software and Hardware Tools
      • Pitch Ranking
      • Mathematical Model of Vowel Perception with the Ineraid Cochlear Implant
    3. Degradation of Speech and Hearing with Bilateral Acoustic Neuromas
    4. Objective Assessment of Vocal Hyperfunction
      • Comparisons Among the Glottal Airflow Waveform, the Electroglottographic Signal, and the Acoustic Spectrum
      • Phonatory Function in Women with Vocal Nodules
    5. Acoustic and Perceptual Effects of Endoscopic Nasal Surgery
    6. Aiding Dysarthric Speakers
  3. Speech Production Planning and Prosody
    1. Interaction Between Prosody and Planning
    2. Some Phrase-level Influences on the Glottal Waveform
  4. Studies of the Acoustics, Perception, and Modeling of Speech Sounds
    1. Use of Transient Reponse to Determine the Natural Frequencies of the Nasal Cavity
    2. Modification of /dh/ by a Preceding Nasal Consonant
    3. Glottal Characteristics of Female Speakers--Acoustic, Physiological, and Perceptual Correlates
    4. The Effect of Emphatic Accent on Contextual Tonal Variation
    5. Time Variation in Mandarin Voiceless Sibilant Spectra
    6. Acoustic and Perceptual Attributes of Fricative Consonants
  5. Models for Lexical Representation and Lexical Access
    1. Theoretical Background
    2. Identification of Landmarks
    3. Automatic Context-sensitive Estimation of Distinctive Features at Landmarks
  6. Development of Computer and Data Processing Facilities