Observing and Recording Speech
1. Auditory - impressionistic method: IPA transcription.
2. Visual examinations:
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Laryngoscope
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Video, photography, Movetrack.
3. Radiographic techniques - especially useful for articulatory measurements.
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X-ray
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X-ray microbeam
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Cinefluorography
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MRI (static and dynamic).
4. Electronic examinations:
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Electromechanical methods
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Electrophysiology.
4.1 Electromechanical methods employ transducers to convert movement
to changes in some electrical quantity (resistance, inductance, capacitance)
yielding measurable changes in e.g. current or voltage.
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Slowly changing changes: voltmeter, oscilloscope.
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Rapidly changing changes: oscilloscope; recording of signals and subsequent
"off-line" analysis.
4.2 Respiration and airflow:
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Plethysmograph
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Air flow transducers mounted in a face mask
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Transducers: strain-gauges, hot-wire anemometer
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Microphone.
4.3 Direct articulatory measurements, e.g., velotrace, strain gauges.
5 Electrophysiological techniques measure currents generated
within or passed through the body:
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Electromyography (muscles)
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Electroglottography (e.g. laryngograph)
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Electropalatography
6. Articulography uses radio-frequency location of tiny coils placed
on the articulators. The location of each coil is determined by triangulation,
according to signal strength.
7. Recording signals:
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Data recorders (adaptation of audio recorders); typically multi-channel
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Analogue-to-digital conversion and subsequent storage on disk.
8. Signal processing of stored signals, e.g. waveform display, spectrography,
f0 and formant tracking.