Abstract Concepts and the Role of Expertise: An fMRI Investigation on Social, Political, and Spatial Domains

Neuroscientific research on conceptual representation has traditionally focused on concrete categories, such as living things and tools, whereas abstract knowledge has only recently received systematic attention. Emerging evidence suggests that abstract concepts do not constitute a homogeneous category but instead encompass distinct domains, including social and affective concepts. According to embodied cognition accounts, the representation of both concrete and abstract concepts is grounded in the neural systems engaged by the experiences through which their meanings are acquired. Building on this framework, the present study investigates the cognitive organization and neural representation of concepts from three abstract domains, namely social, political and spatial, and examines whether greater domain-specific experience modulates their behavioral and neural processing. Twenty-four healthy subjects, characterized for the level of social and political abilities and experience, underwent an fMRI familiarity judgement task involving social, political, and spatial words. Results showed domain-specific patterns of activation. Social concepts preferentially recruited left temporal and medial frontal regions, consistent with the involvement of neural systems supporting social cognition and the integration of socially relevant conceptual information. Political concepts preferentially activated regions belonging to the default mode and executive control networks, potentially reflecting the integration and manipulation of complex and context-dependent knowledge. Spatial concepts preferentially engaged the left posterior inferior temporal gyrus, possibly reflecting the perceptual and visual components inherent to the meaning of some spatial concepts. Behaviorally, participants with higher levels of domain-specific social or political abilities and experience showed greater selectivity in dimensional ratings, assigning higher ratings to concepts along the relevant dimension and lower ratings along non-relevant dimensions. Crucially, higher levels of social and political abilities and experience were associated with reduced BOLD activity in domain-relevant networks, a pattern consistent with the neural efficiency hypothesis and suggesting more efficient processing of abstract conceptual knowledge.