Major depressive disorder (MDD) is a psychiatric disorder characterized by abnormal resting state functional connectivity (rsFC) in various neural networks and especially in default-mode network (DMN). However, inconsistent findings, i.e., increased and decreased DMN rsFC, have been reported, which raise the question for the source of DMN changes in MDD. Testing whether the DMN abnormalities in MDD can be traced to either a local, i.e., intra-network, or a global, i.e., inter-network, source, we conducted a novel sequence of rsFC analyses, i.e., global FC, intra-network FC, and inter-network FC. Moreover, all analyses were conducted without global signal regression (non-GSR) and with GSR in order to identify the impact of specifically the global component of functional connectivity on within-network functional connectivity within specifically the DMN. In MDD our findings demonstrate (i) increased representation of global signal correlation (GSCORR) in DMN regions, as confirmed independently by degree of centrality (DC) and by an independent DMN template, (ii) increased within-network DMN rsFC, (iii) highly increased inter-network rsFC of both lower-and higher order non-DMN networks with DMN, (iv) high accuracy in classifying MDD vs. healthy subjects by using GSCORR as predictor. Further supporting the global, i.e., non-DMN source of within-network rsFC of the DMN, all results were obtained only when including the global signal, i.e., non-GSR, but not when conducting GSR. Together, we show for the first time increased global signal representation within rsFC of DMN as stemming from inter-network sources as distinguished from local sources, i.e., withinor intra-DMN.

Several authors have studied dissociation within the borderline personality disorder (BPD) population and postulated 3 dissociative subgroups. Conversely, other authors suggest that dissociation may play a central role in the development of trauma-related disorders and specifically in BPD. Nevertheless, the role of dissociation in BPD seems to be controversial. Our aim is to perform a meta-analytic review of the literature to evaluate the extent of dissociation in BPD compared to other psychopathological disorders to clarify its role in this specific condition. Ten eligible studies resulted in a total of 2,035 subjects. Results show that levels of dissociation are higher in BPD than in other psychiatric disorders in general, although this difference is moderate and the heterogeneity of effect sizes is large. In particular, individuals with BPD seem to show higher levels of dissociation than those with several psychiatric and personality disorders but not dissociative disorders or posttraumatic stress disorder. These findings support the fact that dissociation is not specifically a core feature of BPD and, in addition, sustain the existence of a continuum of severity within the psychiatric population. Nevertheless, the current work has several limitations related to the paucity of studies included, the heterogeneity of control groups, their clear definition, and the statistical robustness of the results. In addition, our conclusions require future research in order to explain the role of different forms of dissociation and their etiological factors among the psychiatric population. Eventually, we invite clinicians and researchers to systematically evaluate dissociation in order to reach a better diagnosis for a more specific treatment indication.

The concept and the assessment of personality have been extensively discussed in psychoanalysis and in clinical psychology over the years. Nowadays there is large consensus in considering the constructs of the self and relatedness as central criterions to assess the personality and its disturbances. However, the relation between the psychological organization of personality, the construct of the self, and its neuronal correlates remain unclear. Based on the recent empirical data on the neural correlates of the self (and others), on the importance of early relational and attachment experiences, and on the relation with the brain’s spontaneous/resting state activity (rest–self overlap/containment), we propose here a multilayered model of the self with: (i) relational alignment; (ii) self-constitution; (iii) self-manifestation; and (iv) self-expansion. Importantly, these different layers of the self can be characterized by different neuronal correlates—this results in different neuronally grounded configurations or organizations of personality. These layers correspond to different levels of personality organization, such as psychotic (as related to the layer of self-constitution), borderline (as related to the layer of self-manifestation) and neurotic (as related to the layer of self-expansion). Taken together, we provide here for the first time a neurobiologically and clinically grounded model of personality organization, which carries major psychodynamic and neuroscientific implications. The study of the spontaneous activity of the brain, intrinsically related to the self (rest–self overlap/containment) and the interaction with stimuli (rest–stimulus interaction) may represent a further advance in understanding how our default state plays a crucial role in navigating through the internal world and the external reality.