Chapter Summary
In this chapter
we continue our survey of articulation and look at some of the details of
how the articulators constrict the airstream in various ways. We see that
manner of articulation is not a simple feature, but comprises a number of
different and largely independent dimensions. First the articulators may
constrict the airstream to different degrees: either blocking it completely,
or constricting enough to cause air turbulence, or leaving a considerable
gap for the air to pass without turbulence. Secondly, the soft palate may
be raised, preventing nasal airflow, or lowered, allowing such flow.
Thirdly, a closure may be made on the midline of the oral cavity with or
without a lateral opening allowing air to escape over the rims of the
tongue. The rate of release of a closure is the fourth factor
distinguishing speech sounds. A further aspect of manner of articulation
concerns the speed of the whole gesture for the articulation; for taps, the
articulators are in contact for only a very brief period.
A very
important distinction among manners of articulation is also introduced: the
sonorant - obstruent distinction will be referred to again and again in the
coming chapters. Plosives, fricatives and affricates, the obstruents, are
articulated with a constriction that causes air pressure to rise inside the
vocal tract. Other consonants, together with all vowels, are sonorants and
are made with a configuration of the articulators which allows the pressure
inside the vocal tract to be approximately equal to the pressure outside.
The manner of
articulation labels that we introduce are: plosive, affricate, nasal,
fricative (lateral and median), approximant (lateral and median), tap, flap
and trill. These labels complete a very frequently used method of
specifying consonants known as Voice, Place, Manner (VPM) labels.