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 spontaneous activity of the brain is characterized by an elaborate temporal structure with scale-free properties as indexed by the power law exponent (PLE). We test the hypothesis that spontaneous brain activity modulates task-evoked activity during interactions with animate versus inanimate stimuli. For this purpose, we developed a paradigm requiring participants to actively touch either animate (real hand) or inanimate (mannequin hand) stimuli. Behaviorally, participants perceived the animate target as closer in space, temporally more synchronous with their own self, and more personally relevant, compared with the inanimate. Neuronally, we observed a modulation of task-evoked activity by animate versus inanimate interactions in posterior insula, in medial prefrontal cortex, comprising anterior cingulate cortex, and in medial superior frontal gyrus. Among these regions, an increased functional connectivity was shown between posterior insula and perigenual anterior cingulate cortex (PACC) during animate compared with inanimate interactions and during resting state. Importantly, PLE during spontaneous brain activity in PACC correlated positively with PACC task-evoked activity during animate versus inanimate stimuli. In conclusion, we demonstrate that brain spontaneous activity in PACC can be related to the distinction between animate and inanimate stimuli and thus might be specifically tuned to align our brain with its animate environment.