CRL Newsletter

Action and Object Processing across Three Tasks: an fMRI Study of Picture-Naming, Word Reading and Repetition in Italian

Arévalo, A.L.¹, Dick, F.², Della Rosa, P.^3,4, Dronkers, N.F.^5,6,8, Bates, E.A.^6,7, Cappa, S.F.^3,4, & Perani, D.^3,4

¹ Hospital Santa Cruz, Curitiba, Brazil
² School of Psychology, Birkbeck College, London, UK
³ Psychology/Neuroscience, Università Vita Salute San Raffaele, Milan, Italy
⁴ IBFM, CNR, Segrate Milan, Italy
⁵ University of California, Davis, CA, USA
⁶ Center for Research in Language, University of California, San Diego, CA, USA
⁷ Department of Cognitive Science, University of California, San Diego, CA, USA
⁸ Center for Aphasia and Related Disorders, VA Northern California Health Care System, Martinez, CA, USA

Numerous studies have investigated the neural processing of actions versus objects. Some have reported distinct areas subserving each item type, while others have found highly overlapping networks. These inconclusive results could be due to the use of different methodologies and tasks, as well as to the different ways these items are defined -- i.e., as semantic concepts (actions vs. objects) or as lexical/grammatical entities (nouns vs. verbs). The aim of this fMRI study was to evaluate whether the semantic processing of actions and objects can be linked to distinct brain regions, and whether different tasks result in different patterns of activation in the same set of participants. Healthy native speakers of Italian saw and heard action and object stimuli presented in three different ways: black and white line drawings (picture-naming), single printed words (reading), and aurally-presented words (repetition). Overall, across two of the three tasks, actions produced more activation than objects in left precentral gyrus, bilateral middle and superior temporal gyrus, right fusiform gyrus, and right cerebellum. At no time did objects result in greater activation than actions. These findings suggest that the brain networks supporting action and object processing overlap. Furthermore, the fact that the type of task can influence the relative degree of action versus object activation differences most likely reflects the effect of presentation modality (i.e., pictures vs. written/spoken words) on the processing of one conceptual category versus the other.