Behaviorally spontaneous confabulation is a syndrome characterized by reality confusion: patients act according to confabulations, are disoriented and amnesic. One theory, the "reality filtering", hold that patients suffering from such reality confusion have a specific failure of a mechanism supposed to verify whether upcoming memories pertain to the "now", or not. Other theories explain confabulations by a failure in the verification of the precise content of memories (content monitoring as described in the strategic retrieval model) or by a failure in the verification of the context associated with memories (context monitoring as described in the source monitoring framework). In the three studies of the present thesis, the electrophysiological basis and clinical correlates of reality filtering were compared with content and context monitoring. Results showed that reality filtering dissociated from the two monitoring mechanisms and was the strongest predictor of reality confusion as evident in confabulation and disorientation.