Measuring Vocal Tract Behavior

Oral Pharyngeal Function and Speech ProductionTopic 7a. Vocal Tract ReviewStephen M. TaskoLearning ObjectivesDescribe the main cavities of the vocal tract.Identify the major boundaries of each cavity (e.g. hard palate, lips, teeth etc.).

Stephen M. TaskoVocal Tract and BoundariesStephen M. Tasko

Learning ObjectivesProvide the general functions of the major mobile structures within the vocal tract.

Stephen M. TaskoMandibleStephen M. Tasko

TongueStephen M. Tasko

LipsStephen M. Tasko

Learning ObjectivesDescribe, draw and explain how valve and tube analogy of the vocal tract.

Stephen M. TaskoTube and Valve Analogy RevisitedStephen M. TaskoVocal Tract is a system of tubes and valvesTubes create the vocal tract shapeValves can serve toGenerate sound (e.g. larynx)Determine the shape of the vocal tract

Learning ObjectivesDescribe the main control variables of the oropharyngeal function.

Stephen M. TaskoControl Variables Pharyngeal-Oral Lumen Size and ConfigurationPharyngeal-Oral Structural Contact PressurePharyngeal-Oral Airway ResistancePharyngeal-Oral Acoustic ImpedanceStephen M. TaskoPharyngeal-Oral Lumen Size and ConfigurationSize and shape of the oral-pharyngeal cavity dictates how this tube will resonate.Critical variable for determining the filter characteristics of the vocal tractStephen M. Tasko

Pharyngeal-Oral Structural Contact PressureMany phonetic objectives are achieved through establishing contact between structures

Active ForcesMuscularPassive ForcesSurface tensionGravityAeromechanical influencesStephen M. Tasko

Pharyngeal-Oral Airway ResistanceStephen M. Tasko

Pharyngeal-Oral Acoustic ImpedanceStephen M. Tasko

Oral Pharyngeal Function and Speech ProductionTopic 7b. Selected Instrumentation for Capturing Oral-pharyngeal Function

Stephen M. TaskoLearning ObjectivesBriefly describe kinematic methods for capturing oral-pharyngeal function.Briefly describe electropalatography.Briefly describe electrophysiological methods for capturing oral-pharyngeal function.

Stephen M. TaskoX-ray Procedures

CineradiographyUses ionizing radiation to directly view vocal tract structuresTakes full field x-rays of the head at rates exceeding 150 images/secondRadiation exposure very highStephen M. TaskoX-ray ProceduresX-ray MicrobeamDirects a very small x ray beam at radio-opaque markers glued to vocal tract structuresMuch less radiation compared to cineradiographyStephen M. Tasko

19Electromagnetic Articulography(e.g. www.articulograph.de)Stephen M. Tasko

20Ultrasound

Stephen M. Tasko

Functional Magnetic Resonance Imaging

fMRI techniques applied to the vocal tractStephen M. TaskoElectropalatography (EPG)Device used to measure lingua-palatal contactParticipant wears a false palate that contains a series of small transducersWhen contact is made with transducer, it is recorded by instrumentStephen M. Tasko

23Electropalatography (EPG)Stephen M. Tasko

24ElectrophysiologyElectromyography (EMG)Recording of muscle activation patterns (MAPs)May use surface or indwelling (needle or hookwire) electrodes

Stephen M. Tasko