1. Introduction: language history meets psychology Marianne Hundt, Sandra Mollin and Simone E. Pfenninger; Part I. Frequency: 2. The Ecclesiastes principle in language change Harald Baayen, Fabian Tomaschek, Susanne Gahl and Michael Ramscar; 3. Frequencies in diachronic corpora and knowledge of language Martin Hilpert; Part II. Salience: 4. Salience in language usage, learning, and change Nick C. Ellis; 5. Low salience as an enabling factor in morphosyntactic change Elizabeth C. Traugott; Part III. Chunking: 6. Chunking in language usage, learning, and change: I don't know Nick C. Ellis; 7. Chunking and changes in compositionality in context Joan L. Bybee and Carol Lynn Moder; Part IV. Priming: 8. Priming and language change Martin J. Pickering and Simon Garrod; 9. From priming and processing to frequency effects and grammaticalisation? Contracted semi-modals in present-day English Christian Mair; Part V. Analogy: 10. The role of analogy in language processing and acquisition Heike Behrens; 11. The role of analogy in language change: supporting constructions Hendrik de Smet and Olga Fischer; Part VI. Ambiguity: 12. Syntactic ambiguity in real-time language processing and diachronic change Claudia Felser; 13. Ambiguity and vagueness in historical change David Denison; Part VII. Acquisition and Transmission: 14. Developing language from usage: explaining errors Elena V. M. Lieven; 15. Transferring insights from child language acquisition to diachronic change (and vice versa) María José López-Cous.