Imitation and utilisation behaviour

Abstract

Objective - To investigate the incidence, anatomical correlates, and clinical features of imitation and utilisation behaviour, which are thought by Lhermitte and coworkers to represent a reliable and frequent index of frontal lobe disease. Methods - 78 patients with hemispheric focal lesions were tested in two separate sessions, in which their reactions to a series of gestures performed by the examiner and to the presentation of a set of objects were recorded. The patients were stratified into a frontal (n = 52) and a non-frontal group (n = 26) on the basis of their CT data. Results and conclusions - Imitation behaviour was present in 39% of the frontal patients and was mainly associated with medial and lateral lesions, at odds with the claim of Lhermitte et al. that it is a constant accompaniment of lower, mediobasal lesions. in the non-frontal group it was found in three patients, all with damage to the deep nuclei region. Utilisation behaviour was a much rarer phenomenon, present in only two patients, both of whom had frontal damage. Neither imitation behaviour nor utilisation behaviour were found in patients with retrorolandic cortical lesions.