Anatomical Explorations of Mind: Studies with Modern Imaging Techniques

Theories of how single words are processed by the normal human brain have been developed through studies of patients with various lesions affecting areas of the brain thought o be important in language pro-cessing (LaBerge and Samuels 1974; Damasio 1984; Coltheart 1985). From these studies, two general theories have emerged: a serial model that posits infor-mation flow in an obligatory, stepwise fashion from perception to speech, and a parallel model that posits a flexible modular organization governed by specific in-formation processing requirements hat can vary under particular circumstances. We have studied the process-ing of single words in normal adult humans using posi-tron emission tomography (PET) to determine whether either of these theories best explains the manner i