On feature spreading and the representation of place of articulation

Since Clements (1985) introduced feature geometry, four major innovations have been proposed: Unified Feature Theory, Vowel-Place Theory, Strict Locality, and Partial Spreading. We set out the problems that each innovation encounters and propose a new model of feature geometry and feature spreading that is not subject to these problems. Of the four innovations, the new model - Revised Articulator Theory (RAT) - keeps Partial Spreading, but rejects the rest. RAT also introduces a new type of unary feature - one for each articulator - to indicate that the articulator is the designated articulator of the segment.