A case of progressive supranuclear palsy characterized by a loss of self-activation and a compulsive behaviour of the obsessive type is reported. The pathological examination was remarkable for the intensity of pallidal lesions and their diffusion to both the external and internal segments. While the loss of self-activation seemed to result from a damaged cortico-subcortical circuit forming a limbic loop, the compulsive behaviour of the obsessive type may have resulted from the interruption of a frontal-caudal-pallidal-luysian circuit.