The characteristics of naming deficits in semantic dementia of early stages

Abstract

We investigated naming disorders in a case of semantic dementia in the early stage of the disease. The patient was a 55-year-old right-handed woman. Her chief complaint was that she could only remember the first letter of the surnames of her acquaintances. She had atrophy of the rostral left temporal lobe and reduced blood flow in the left inferior temporal lobe. We administered a test of naming and auditory comprehension in the "A Test of Lexical Processing in Aphasia". The results showed that, for the same target word, naming was often incorrect, while auditory comprehension was correct. Naming errors included circumlocution, verbal paraphasia, and tip-of-the-tongue phenomenon (answering the initial sound or number of syllables of the target word). These errors showed different characteristics depending on whether auditory comprehension was correct or not. These findings suggest that the naming disorder in this case was due to a slight loss of semantic memory and a lexical retrieval disorder.