Neural specialisation for concrete and abstract concepts revealed through meta-analysis

Abstract Identifying the brain regions that process concrete and abstract concepts is key to understanding the neural architecture of thought, memory and language. We review current theories of concreteness effects and test their neural predictions in a meta-analysis of 72 neuroimaging studies (1400 participants). Concrete concepts preferentially activated visual and action processing regions, particularly when presented in sentences. Abstract concepts preferentially activated networks for social cognition (particularly for sentences), and for language and semantic control (particularly when presented as single words). These results suggest that concrete and abstract concepts vary both in the information-processing modalities they engage and in the demands they place on cognitive control processes. Specialisation for both concept types was present in different parts of the default mode network (DMN), with effects dissociating along a social-spatial axis. Concrete concepts generated greater activation in a medial temporal DMN component, implicated in constructing mental models of spatial contexts and scenes. In contrast, abstract concepts showed greater activation in frontotemporal DMN regions involved in theory-of-mind and language processing. These results support prior claims that generating models of situations and events is a core DMN function and further indicate specialisation within DMN for different aspects of these models. Public significance statement The distinction between concrete and abstract concepts is fundamental to language and cognition. Here, we present the largest meta-analysis of neuroimaging studies experiments investigating this distinction, including data from 1400 participants. Our results indicate that concrete and abstract language differentially engages a range of neural systems involved in perception, action, language and social processing. These results provide new insights into how the brain constructs representations of the world from linguistic information, and into the neural basis of imagination.