“…Positron emission tomography (PET) makes it possible to observe active cerebral areas while normal subjects process language (Alavi, Reivich, Greenberg, Hand, Rosenquist, Rintelman, Christman, Fowler, Goldman, MacGregor, & Wolf, 1981;Mazziotta, Phelps, Carson, & Kuhl, 1982;Mazziotta, Phelps, & Halgren, 1983;Kushner, Schwartz, Alavi, Dann, Rosen, Silver, & Reivich, 1987;Petersen, Fox, Posner, Mintun, & Raichle, 1988 , 1991). So far, PET studies have mainly examined the cortical anatomy of single-word comprehension and production (Petersen et al, 1988Wise et al, 1991;Frith et al, 1991).…”