The emergence of linguistic form in time

Where do linguistic forms come from? Researchers have proposed accounts based on rules, conventions, constraints, statistical regularities, discourse patterns, language contact, neurology, physical dynamics and genes. What is common to all of these forces is that they must all make their final impact at the moment of speaking. Some of these forces operate within a narrow time frame. For example, when we run up a flight of stairs, there will be an immediate impact on vocal production leading to loss of weak syllables and changes in pitch. This type of exertion has a quick and immediate effect on prosodic and phonetic form. Other processes have a slower time fuse. For example, we may not have made reference to some concept, such as ‘apotheosis’ or ‘ligature’ for years. Yet, when we need to use these words, we can dredge them up out of our memories and apply them in the moment. The effects of Alzheimer’s disease on language can work across decades, leading eventually to an inability to remember even the most common words. Languages themselves undergo changes at a truly glacial pace. For example, the shift in Old English from subject-object-verb (SOV) to subject-verb-object (SVO) word order took centuries to complete. These various forces constitute dynamical systems operating with very different time frames and histories. What binds all of these systems together is the fact that they must all mesh in the current moment. One simple view of the process of meshing is that cues combine in an additive manner (Massaro 1987) and that systems are partially decomposable (Simon 1969). However, psycholinguistic work in the Competition Model framework (MacWhinney in press) has shown that simple cue summation applies only when decisions are not made online. For online decisions, cues interact in far more complex ways, determined by the periodicity linked to their operation. For example, the advantage of first mention will maintain its effect across