Kissing and dancing - a test to distinguish the lexical and conceptual contributions to noun/verb and action/object dissociation. Preliminary results in patients with frontotemporal dementia

Dissociations between the processing of nouns and verbs are well recognised in a number of neurological diseases. Anatomically, deficits in verb processing have been linked to the anterior (frontal), those of noun processing to the posterior (temporal) cortical regions of the dominant hemisphere. It remains, however, unclear whether this difference is due to linguistic (verbs versus nouns) or conceptual (actions versus objects) properties. To address this issue, we designed a novel test (the kissing and dancing test, KDT) consisting of 52 triplets of pictures depicting actions and 52 word triplets consisting of verbs, which was directly comparable with the 52 triplets of objects and nouns of the pyramids and palmtrees test (PPT). The two tests were validated in conjunction first on a normal control group, followed by assessments of 10 patients with the frontal variant frontotemporal dementia (fVFTD) and 14 patients with semantic dementia (SD). The patients with fVFTD were consistently more impaired on the KDT, those with SD on the PPT. Although the difference was found for both pictures and words, it was significant only for pictures in fvFTD and for words in SD. The results suggest that both linguistic and conceptual aspects play a role in the observed dissociation, but that their impact in frontal and temporal variants of FTD might be different. (C) 2002 Elsevier Science Ltd. All rights reserved.