Preaspiration in the Nordic Languages: Synchronic and Diachronic ...

2.6 Auditory constraints and the rarity of
preaspiration
The apparent rarity of normative preaspiration in the world’s languages
has not received much attention in the literature. One of the few extant
accounts that deals with the issue of on an empirical basis is Bladon’s
(1986) explanation of the rarity of preaspiration in terms of auditory constraints.
Drawing mostly on the research of Delgutte (1980, 1982), Bladon
has established a set of general principles of audition. These principles
act as constraints on the possible sound patterns of languages. Sound
patterns that, in some way, provide good perceptual discriminability are
favoured over those that result in poor discriminability. In this way, Bladon
tries to explain some general tendencies in the sound patterns in languages.
Of the constraints proposed by Bladon, mainly two are of concern
here: On/off response asymmetry and Short-term adaptation. As for
On/off response asymmetry, Bladon proposes that “spectral changes
whose response in the auditory nerve is mainly onset of firing are much
more perceptually salient than those producing an offset.” Using preaspiration
as an example, Bladon points out that any temporal information
for the preaspiration relies entirely on the detection of offsets, rather than
onsets, which is poor in terms of salience. Postaspiration, on the other
hand, is optimally salient from this point of view, since it is preceded by
a silence.
And as regards Short-term adaptation, Bladon refers to Delgutte’s
(1980, 1982) work, saying that “after a rapid onset of auditory nerve discharge
at a particular frequency, there is a decay to a moderate level of
discharge even though the same speech sound is continuing to be produced.”
Turning to preaspiration again, Bladon notes that, unlike postaspiration,
preaspiration is subject to widespread short-term adaptation.
This results from the fact that a vowel and a following preaspiration have
very similar spectral characteristics and therefore there is little chance of
neural recovery before the onset of preaspiration.
Thus, preaspiration takes pride of place among Bladon’s examples of
sound patterns that are bad for audition. In fact, Bladon describes preaspiration
as an “auditory phonetic dinosaur” that could hardly be less
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