Loss of autonomy in humans: utilisation and imitation behaviour.

In 1981, when Francois Lhermitte described utilisation behaviour, his exper ience was based on 40 patients with bilateral frontal lesions and 5 cases o f unilateral lesions. This behaviour was never observed in normal subjects or in patients whose lesions spared the frontal lobes. The description of i mitation behaviour followed shortly after In 1986, of the 125 patients stud ied 40 presented an imitation behaviour without utilisation behaviour, 35 h ad both types of abnormal behaviour and 50 had neither. Continuing his stud y of patients presenting a frontal syndrome, Lhermitte showed that dependen ce on objects and dependence on individuals can be prolonged in the form of a dependence on social context which ultimately characterises the loss of autonomy. Lastly, in 1993, he noticed that certain major depressive states gave rise to an utilisation and imitation behaviour similar to the type of behaviour resulting from a frontal syndrome of organic origin. The concept of loss of autonomy must be discussed in relation to the notion of intentionality of the various manifestations of loss of autonomy Pathol ogical prehension and the grasping reflex no longer provide a satisfactory explanation. Electrophysiology and the study of regional activity in the ce rebral cortex associated with the preparation and execution of the movement have led to these phenomena being viewed in a new light With the concept o f loss of autonomy, the distinction between the mechanisms underlying inten tion and those which modulate actions in response to external demands is no w seen to be well-founded Francois Lhermitte opened the way.