Syntactic abilities vary across individuals. Weak syntax is typically ascribed to limited competence (knowledge) or poor performance (processing). However, with many questioning this dichotomy, alternative explanations should be considered. Arguments related to language exposure are insufficient because language-impaired children often have good…

The article first discusses some recent work in time perception--in particular the distinction among prospective timing, retrospective timing, and passage of time judgments. The history and application of an "internal clock" model as an explanation of prospective timing performance is reviewed and contrasted with the different mechanisms needed…