Strengthening, Weakening and Variability: The Articulatory Correlates of Hypo- and Hyper-articulation in the Production of English Dental Fricatives

A number of influential approaches to understanding phonetic and phonological variation in speech have highlighted the importance of functional factors (Blevins, 2004; Donegan & Stampe, 1979; Kiparsky, 1988; Kirchner, 1998; Lindblom, 1990). Under such approaches, speaker- and listener-oriented principles—ease of articulation vs. perceptual clarity—often work in opposite directions with respect to consonantal articulation. Minimization of effort is thought to drive a general “weakening” of consonants (resulting in decreased articulatory constriction and/or duration) which often makes them more articulatorily similar to surrounding sounds. This can result in assimilation, lenition, and ultimately deletion, and generally comes at the expense of clarity. By contrast, maximization of clarity drives consonantal “strengthening” processes (resulting in increased articulatory constriction and/or duration) that makes target segments more distinct from neighboring sounds, which can result in fortition. Clear speech generally involves more extreme or “forceful” articulations, and usually comes at the expense of requiring more articulatory effort from the speaker