A neural mapping hypothesis to explain why velar stops have an allophonic split

Velar stops are phonetically characterized by two allophones-a palatal "g" when produced in front-vowel contexts and a velar "g'' when produced in bac k-vowel contexts. Acoustic characterizations of velar stops based on plotti ng the onset and offset frequencies of the second formant transition clearl y reveal two acoustically separated allophonic groups. Using cross-linguist ic acoustic data, it is shown that alveolar stops fall precisely within the acoustic void created by the velar allophones. A neural-based mapping hypo thesis is put forth claiming that the bimodal distribution of velars is an instance of articulatory behavior acting in the service of auditory represe ntation. (C) 1999 Academic Press.