Speech Science Speech production I – Breathing
Topics Energy for speech The physical structures Controlling breathing in speech Homework: a) Kent, Chap. 4, pp b) Borden, Harris & Raphael, Chap. 4, pp /70-83 Deutsch: c) Pompino-Marschall, Teil II, pp Übung 3 (hand in by 19 th Nov): See question sheet.
Breathing: Energy for speech The airstream provides kinetic energy which is transformed into acoustic energy for speech The normal airstream for speech is produced by breathing outwards (called an egressive pulmonic airstream) There are several other (egressive and ingressive) airstream mechanisms which are used for speech (in “more exotic” languages) The transformation of the kinetic energy into the acoustic energy needed for speech comes later – first things first!
High to low pressure = airstream Like the wind in our weather systems, Our breath moves from high- to low-pressure regions To breath in, we reduce the pressure in our lungs, and the air flows in (if we open our mouth!); to breath out we increase the lung pressure. We do this by lowering or raising our diaphragm and by raising and lowering our rib-cage. This increases or reduces the volume of our lungs, which reduces or increases the pressure in them (QED!)
The physical structures 1
The physical structures 2 Seen from front Seen from back
The physical structures 3 Seen from front Seen from back
The physical structures 4
The physical structures 5 Balance of forces Lungs and thorax together Thorax alone Lungs alone
Breathing control
Breathing control … … is different for speech than for living. Breathing out is carefully controlled (and takes longer) More air is breathed in (and out) than in normal, relaxed breathing
Breathing control for speech I The loudness of an utterance increases with increased airflow We control loudness in speech; therefore we modify the pressure and flow – it is different from normal “breathing to live“. Changing airflow (volume- velocity) is the result of changing pressure within the lungs.
After breathing in, the relaxation pressure is too high for the required loudness Inspiratory effort is necessary to reduce the excess pressure. Breathing control for speech II
Breathing control for speech III Different loudnesses require different lung pressures This means that for louder speech less time is needed to counteract the excess relaxation pressure
Breathing control for speech IV Inspiration muscles Expiration muscles EMG data show that muscles of inspiration are used to work against the excess relaxation pressure… … and that active expiration takes over when relaxation pressure = required pressure
Non-pulmonic air-stream mechanisms We mentioned other air-stream mechanisms for speech than egressive pulmonic air. They are: The egressive glottalic air-stream (for producing “ejective“ sounds) The ingressive glottalic air-stream (for producing “implosive“ sounds) The ingressive velaric air-stream (for producing “click“ sounds
The egressive glottalic air-stream
The ingressive glottalic air-stream
The ingressive velaric air-stream