THE SUBCORTICAL FOUNDATIONS OF GRAMMATICALIZATION GIORGOS P. ARGYROPOULOS Language Evolution and Computation Research Unit, University of Edinburgh 40 George Square, Edinburgh, EH8 9LL, Scotland, UK giorgos@ling.ed.ac.uk The present paper raises the so far unaddressed question of the neurolinguistic processes underlying grammaticalization operations. Two adaptive mechanisms are presented, based on current research on the subcortical contributions to aspects of higher cognition: The cerebellar-induced Kalman gain reduction in linguistic processing, and the basal ganglionic re-regulation of cortical unification operations. 1. Introduction The neuroanatomy of either the domain-general cognitive phenomena underlying grammaticalization, e.g., “ritualization” (Haiman, 1994), “automatization” (Givón, 1979; Bybee, 1998), or the particular psycholinguistic processes, e.g., Pickering and Garrod’s (2004) dialogical “routinization”, has hardly attracted any attention in the literature. Haiman’s (1994, p.25) comment, that “the physiology of ritualization in human beings is unknown”, is rather suggestive. The desideratum, then, is to move from the sine qua non of the neural grounding of such putative domain-general cognitive phenomena to a neurolinguistics of grammaticalization, by introducing I-language adaptation processes (both representational fine-tuning and executional optimization) in accordance with changing E-language properties. 2. The Explanandum of Grammaticalization Grammaticalization, “an evolution whereby linguistic units lose in semantic complexity, pragmatic significance, syntactic freedom, and phonetic substance” (Heine & Reh, 1984, p.15), is a manifestation of the “Reducing Effect” of repetition in linguistic behaviour (Bybee & Thompson, 2000): “Univerbation” (Lehmann, 1995), i.e., the gain in syntagmatic bondedness (e.g., hac hora (Latin) > ahora (Spanish)), “phonetic attrition” (Givón, 1979), i.e., the minimization of articulatory gestures (e.g., going to > gonna),