Identification without naming: a functional neuroimaging study of an anemic patient

The neural correlates of identification and name retrieval have proved diff icult to characterise because both occur highly automatically in normal lan guage processing. Thus, although some evidence points to the left anterior temporal cortex (ATC) as a brain region underlying these functions, its rel ative role in semantic and lexical retrieval processes is still a matter of debate. Positron emission tomography (PET) was used to measure regional ce rebral blood flow responses to famous and non-famous visually presented fac es and buildings in a severely anemic patient and in six control subjects, while they were performing a same-different matching task. Because the pati ent was able to identify the stimuli that he could not name, it was possibl e to investigate whether the left ATC would respond when identification occ urred without name retrieval. Both the patient and the controls activated t he left ATC when famous stimuli were compared with non-famous stimuli. This result supports the hypothesis of a predominantly semantic function of the left ATC.