In the present studies, we evaluated the contributions of language and sensorimotor information to the representation of abstract and concrete words and the possibility that the organizations of the two types of concepts follow different organizational principles: association, for abstract concepts, and semantic similarity, for concrete concepts. In Study 1, we examined the two strongest associates of concrete and abstract words from published free association norms. Study 2 then extended this analysis to individual data collected with a free association task. Language associations were more important for abstract than for concrete words, but for sensorimotor information no differences were observed between the two types of concepts. Also, no clear evidence was found for different qualitative organizational principles for abstract and concrete concepts. Multiple representational systems thus seem to be engaged in the conceptual processing of abstract and concrete concepts, while it remains to be investigated whether their representations follow different organizational principles.Keywords Abstract . Concrete . Language . Sensorimotor information . Free associationIn recent years, a diverse set of models regarding conceptual knowledge have proposed that multiple representational systems are engaged in conceptual processing (Andrews, Vigliocco, & Vinson, 2009;Barsalou, Santos, Simmons, & Wilson, 2008;Dove, 2009Dove, , 2011Louwerse & Jeuniaux, 2008Simmons, Hamann, Harenski, Hu, & Barsalou, 2008;Steyvers, 2010). In particular, they have all considered that both more sensorimotor-based information and languagebased information play a role in conceptual representation, thus recapturing the ideas first proposed by Paivio (1971Paivio ( , 1986 in the context of the dual-code theory.This general perspective of the involvement of language and sensorimotor information in conceptual representation is particularly discussed regarding the processing and representation of abstract and concrete concepts. Again, these models agree on a general division of labor in the acquisition of these two types of concepts, with concrete concepts being largely learned through sensorimotor experience, and abstract concepts being largely learned through linguistic experience (Andrews et al., 2009;Crutch & Warrington, 2005;Dove, 2009Dove, , 2011Louwerse & Jeuniaux, 2010;Steyvers, 2010). The behavioral data supporting this proposal, however, are still recent and limited. Nevertheless, evidence from both neuropsychological (e.g., Breedin, Saffran, & Coslett, 1994;Crutch & Warrington, 2005;Warrington, 1981) and neuroimaging (e.g., Binder, 2007;Sabsevitz, Medler, Seidenberg, & Binder, 2005) studies converge to show that these two types of concepts differentially activate the brain areas involved in sensorimotor and language representation.Where the models clearly diverge is on whether this division should also entail different organizational principles in terms of conceptual representation. Most models have assumed that the difference betwee...