Associated production and comprehension deficits for people's names following left temporal lesion

We report the case of a patient who presented, following a left temporal stroke, the unique association of word production and word comprehension deficits, both highly selective for people's names. The patient was unable to retrieve the names of familiar people on presentation of their face or on verbal description, contrasting with the preserved ability to produce other kinds of names. He could, however, provide rich and accurate biographical comments about target faces that he could not name, showing that biographical knowledge was intact. Furthermore, the dramatic effect of phonological cueing suggested that output word forms were also intact, but partially disconnected from the store of biographical knowledge. Additionally, the patient presented a severe deficit in understanding people's names, again contrasting with a preserved comprehension of other categories of proper and common names. Good performance in a lexical decision task with familiar people's names demonstrated that input word forms were intact, and pointed to a mirror disconnection between input word forms and biographical knowledge. The patient's deficit could thus be summarized as a two-way disconnection between biographical and lexical knowledge, restricted to human beings. We speculate that this disconnection may reflect the role of the hippocampal and parahippocampal formations in binding together different types of knowledge stored in distant neocortical areas. The categorial specificity of the deficit may result from the topographical separation of semantic categories within these temporal convergence zones.