This review discusses the contributions of functional imaging (fMRI/PET) to our understanding of how semantic concepts are represented and processed in the human brain. The sensory-motor theory of semantic memory suggests that semantic processing relies on reactivation of sensory-motor representations that were involved in perception and action. More specifically, it attributes an apparent category-specific (e.g. tool vs. animals) organization of semantics to anatomical segregation for different semantic features (e.g. action vs. visual). Within this framework, we will review functional imaging evidence that semantic processing of tools and actions may rely on activations within the visuo-motor system.
