The Neural Representation of Abstract Words: The Role of Emotion Gabriella Vigliocco 1 , Stavroula-Thaleia Kousta 2 , Pasquale Anthony Della Rosa 3 , David P. Vinson 1 , Marco Tettamanti 3 , Joseph T. Devlin 1 and Stefano F. Cappa 3 1 Cognitive, Perceptual and Brain Sciences Research Department, Division of Psychology and Language Sciences, University College London, London WC1H OAP, UK, 2 Trends in Cognitive Sciences, Cell Press, Cambridge, MA 02142, USA and 3 Vita-Salute University and San Raffaele Scientific Institute, DIBIT, Milan 20132, Italy Address correspondence to Gabriella Vigliocco, Cognitive, Perceptual and Brain Sciences Research Department, Division of Psychologyand Language Sciences, University College London, London, UK. Email: g.vigliocco@ucl.ac.uk It is generally assumed that abstract concepts are linguistically coded, in line with imaging evidence of greater engagement of the left perisylvian language network for abstract than concrete words (Binder JR, Desai RH, Graves WW, Conant LL. 2009. Where is the semantic system? A critical review and meta-analysis of 120 func- tional neuroimaging studies. Cerebral Cortex. 19:2767–2796; Wang J, Conder JA, Blitzer DN, Shinkareva SV. 2010. Neural represen- tation of abstract and concrete concepts: A meta-analysis of neuroi- maging studies. Hum Brain Map. 31:1459–1468). Recent behavioral work, which used tighter matching of items than previous studies, however, suggests that abstract concepts also entail affective pro- cessing to a greater extent than concrete concepts (Kousta S-T, Vigliocco G, Vinson DP, Andrews M, Del Campo E. The represen- tation of abstract words: Why emotion matters. J Exp Psychol Gen. 140:14–34). Here we report a functional magnetic resonance imaging experiment that shows greater engagement of the rostral anterior cingulate cortex, an area associated with emotion proces- sing (e.g., Etkin A, Egner T, Peraza DM, Kandel ER, Hirsch J. 2006. Resolving emotional conflict: A role for the rostral anterior cingulate cortex in modulating activity in the amygdala. Neuron. 52:871), in abstract processing. For abstract words, activation in this area was modulated by the hedonic valence (degree of positive or negative af- fective association) of our items. A correlation analysis of more than 1,400 English words further showed that abstract words, in general, receive higher ratings for affective associations (both valence and arousal) than concrete words, supporting the view that engagement of emotional processing is generally required for processing abstract words. We argue that these results support embodiment views of semantic representation, according to which, whereas concrete con- cepts are grounded in our sensory–motor experience, affective experience is crucial in the grounding of abstract concepts. Keywords: abstract words, anterior cingulate cortex, emotion processing, fMRI, lexical decision, rostral ACC, semantic memory Introduction The distinction between concrete and abstract entities is an ontological distinction based on whether the concepts refer to something that can be perceived and acted upon or whether it is only internally represented (Hale 1988). What makes humans capable of representing abstract concepts? One obvious candidate is language, a symbolic system allowing knowledge not referring to the here and now, to be learnt and shared. After all, it is obvious that we learn abstract words and concepts by being told what they mean (e.g., in school) or by implicitly extracting statistical information re- garding their meaning from linguistic input (Andrews et al. 2009). Indeed, abstract words tend to be learnt later than concrete words, once language is solidly established, and formal education has begun. According to Age of Acquisition norms (i.e., judgments by adult native speakers on when they acquired given words; Stadthagen-Gonzalez and Davis 2006), only 10% of 3-year-olds’ vocabulary is abstract, rising to 25% in 5-year-olds. Acquisition of abstract concepts then increases steadily: >60% of 11-year-olds’ vocabulary is abstract. Two dominant cognitive theories of the differences between con- crete and abstract concepts and words, namely the Dual Coding theory (Paivio 1971, 2007) and the Context Avail- ability hypothesis (Schwanenflugel and Shoben 1983; Schwa- nenflugel 1991), agree in assuming that linguistic processing plays a pivotal role in learning and processing abstract con- cepts. These theories differ with regards to how differences between concrete and abstract processing come about. Dual Coding argues that concrete words would be represented in two distinct formats, a verbal and a non-verbal, imagistic, code, whereas abstract concepts would be primarily or solely represented in a verbal code (e.g., Paivio 2007). In contrast, Context Availability accounts for differences between concrete and abstract concepts as a consequence of how they are rep- resented in verbal memory, with stronger and denser associ- ations with contextual knowledge for concrete than abstract words (Schwanenflugel 1991). Imaging studies in general provide evidence supporting the idea of a greater role of linguistic processing for abstract concepts. Abstract processing has been associated with higher activation in left hemispheric areas involved in linguistic pro- cessing/verbal semantics such as the left inferior frontal gyrus (e.g., Perani et al. 1999; Jessen et al. 2000; Fiebach and Frie- derici 2003; Noppeney and Price 2004; Binder et al. 2005) and the superior temporal cortex (Mellet et al. 1998; Kiehl et al. 1999; Wise et al. 2000; Binder et al. 2005; see Binder et al. 2009 and Wang et al. 2010 for reviews and meta-analyses). Recent lesion and transcranial magnetic stimulation work further converge in supporting a role for the left ventrolateral prefrontal cortex in the processing of abstract words and concepts (Hoffman et al. 2010). It is, however, the case that in these previous studies ab- stract stimuli tended to differ from concrete words on a number of additional dimensions. For example, whereas most studies controlled for differences in frequency between con- crete and abstract words, many of the studies above did not control for differences in familiarity, leading to comparisons between more familiar (and therefore easier to process) con- crete (e.g., artichoke) and less familiar, abstract (e.g., heresy) words. Moreover, in the literature it is invariably assumed that the psycholinguistic constructs of concreteness and imageabil- ity tap into the same underlying theoretical construct, i.e., the © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com Cerebral Cortex July 2014;24:1767–1777 doi:10.1093/cercor/bht025 Advance Access publication February 13, 2013 Downloaded from https://academic.oup.com/cercor/article-abstract/24/7/1767/292586 by guest on 25 December 2018