It is thought a depth psychosis literature review, that we have, in a first time, highlighted various positions within the psychiatric nosography, in an historic and then, in a current context. We cross a perspective called objective to an approach more subjective, however very rewarding: the metapsychological model, whose milestones were thrown by Freud (1911, 1920, 1924, 1940). In addition, we highlighted an opposition between Freud and Bleuler thought their epistolary exchanges published in 2016 in French. This about, question of autism that Freud (1911) designated as well as a retreat of the libido on the Ego; contrarily to Bleuler (1911). To us, that epistemological and theoretical cleavages, have influenced the current nosography (DSM-5, A.P.A., 2013). The empirical research developed in this thesis, aimed at the study of dissociated psychosis through a clinical and projective compared approaches. Indeed, this research is composed by many studies: the first was aimed at the statistical comparisons of Rorschach’s indicators (Nina Rausch de Traubenberg, 1990) between non-clinical population ([n= 310], (de) Tychey et al., 2012) and clinical population, psychiatrist, and more specifically: psychosis dissociated ([in]patient [n= 81]). Within the first study, in a second time, we proceeded to the statistical comparisons between the three subgroups of the sample, constitute of: 25 subjects diagnosed with paranoia, 30 subjects diagnosed with schizophrenia and 26 diagnosed with paranoid schizophrenia. All diagnostics were realized in double bind et and according to a double approach (psychoanalytic and psychiatrist). The second study is a qualitative analysis contrasted, devoted to the deeply psychic investigation of exemplary clinical cases, representatively of three subgroups from the population’s study (paranoia; schizophrenia paranoid; pure schizophrenia). The sample is itself constituted of limits’ subgroups suffering from psychotic decompensations and hospitalized on a long court. In the qualitative study of clinical contrasted cases, we presented firstly, a subject from a pure paranoia structure: Catherine, an autopunitive feminine paranoia case.Secondly, we presented the analysis of a clinical picture from schizophrenic structure: Joseph, from which megalomaniac Ego and invasive delirium will surely arrested the lector; and finally, we analysed a pure schizophrenia case: Doug, which psychic desert particularly challenges us in conter-transferential’s dynamic. Then, to illustrated closer that we understand by sliding of an a-structure to a dissociated psychosis (and not to a melancholic proceed, as well as that is permitted by Bergeret [1974]), we analysed the cases of Jordan and Ali. Ali was initially inscribed in an a-structure (Bergeret, 1974), from which he decompensed secondarily in a paranoiac organisation; Jordan on other hands, decompensed secondarily in a pure schizophrenia