The sense of self in the aftermath of trauma: lessons from the default mode network in posttraumatic stress disorder

Abstract

Trauma can profoundly affect the sense of self, where both cognitive and somatic disturbances to the sense of self are reported clinically by individuals with posttraumatic stress disorder (PTSD). These disturbances are captured eloquently by clinical accounts, such as, 'I do not know myself anymore,' 'I will never be able to experience normal emotions again,' and, 'I feel dead inside.' Self-related thoughts and experiences are represented neurobiologically by a large-scale, cortical network located along the brain's mid-line and referred to as the default mode network (DMN). Recruited predominantly during rest in healthy participants, the DMN is also active during self-referential and autobiographical memory processing-processes which, collectively, are thought to provide the foundation for a stable sense of self that persists across time and may be available for conscious access. In participants with PTSD, however, the DMN shows substantially reduced resting-state functional connectivity as compared to healthy individuals, with greater reductions associated with heightened PTSD symptom severity. Critically, individuals with PTSD describe frequently that their traumatic experiences have become intimately linked to their perceived sense of self, a perception which may be mediated, in part, by alterations in the DMN. Accordingly, identification of alterations in the functional connectivity of the DMN during rest, and during subliminal, trauma-related stimulus conditions, has the potential to offer critical insight into the dynamic interplay between trauma-and self-related processing in PTSD. Here, we discuss DMN-related alterations during these conditions, pointing further towards the clinical significance of these findings in relation to past-and present-centred therapies for the treatment of PTSD. El sentido del Yo luego de experimentar Trastorno de Estrés Postraumático: Lesiones desde la Red Neuronal por defecto

A randomized, controlled trial of alpha-rhythm EEG neurofeedback in posttraumatic stress disorder: A preliminary investigation showing evidence of decreased PTSD symptoms and restored default mode and salience network connectivity using fMRI

“…In line with our hypotheses, we found increased precuneus connectivity with the pDMN and increased anterior dACC connectivity with the aDMN among PTSD patients at baseline as compared to healthy individuals. Indeed, such DMN functional disruptions in PTSD patients are hypothesized to mediate negative self-referential thoughts as well as altered social cognition, bodily self-consciousness, and autobiographical memory related to trauma ( Cavanna and Trimble, 2006 ; Bluhm et al, 2009 ; Daniels et al, 2010 ; Van der Kolk, 2014 ; Tursich et al, 2015b , Akiki et al, 2017 , Fenster et al, 2018 , Frewen et al, 2020 ; Lanius et al, 2020 ). After the NFB intervention , the PTSD experimental group displayed a decrease in precuneus connectivity with the pDMN as compared to baseline.…”

“…The default mode network (DMN) possesses core nodes within the posterior cingulate cortex (PCC), precuneus, ventromedial prefrontal cortex (vmPFC), dorsomedial PFC (dmPFC), and hippocampus ( Greicius et al, 2003 , Buckner et al, 2008 , Spreng et al, 2008 , Qin and Northoff, 2011 ). DMN functional disruptions in PTSD patients are hypothesized to be related to modified and often negative self-referential thoughts, as well as to altered social cognition and autobiographical memory in the aftermath of trauma ( Bluhm et al, 2009 ; Daniels et al, 2010 ; Van der Kolk, 2014 ; Tursich et al, 2015b , Akiki et al, 2017 , Fenster et al, 2018 , Frewen et al, 2020 ; Lanius et al, 2020 ). Studies investigating DMN functional connectivity at rest in PTSD report disrupted connectivity among multiple DMN structures ( Bluhm et al, 2009 , Sripada et al, 2012 , Chen and Etkin, 2013 , Lanius et al, 2015 , Tursich et al, 2015b , Yehuda et al, 2015 , Koch et al, 2016 , Akiki et al, 2017 , Barredo et al, 2018 , Nicholson et al, 2020a ).…”

Reward Processing and Circuit Dysregulation in Posttraumatic Stress Disorder

“…More specifically, hyper-activation of insula, amygdala, and dorsal anterior cingulate cortex (dACC), as well as hypoactivation in ventral medial PFC (vmPFC) and impaired hippocampal function have been consistently reported (2,27,28). Furthermore, PTSD has been found to be associated with decreased functional connectivity within Default Mode Network (DMN, linked to self-referential processing and mind wandering with key nodes in PCC, vmPFC /sgPFC, and hippocampus), increased connectivity within Salience Network (SN, responsible for salience/threat detection and comprised of amygdala, insula and dACC), as well as with specific patterns of DMN-SN functional desegregation (26,(29)(30)(31). Alterations in relationships of DMN and SN with other networks such as Frontoparietal Network (FPN, involved in "top-down, " control emotional regulation and includes prefrontal cortical regions such as dlPFC), Dorsal Attention Network (DAN, involved in topdown voluntary orienting and comprised of MFG, posterior parietal lobe and frontal eyes fields) and Ventral Attention Network (VAN, linked to alerting and reorienting attention to unexpected stimuli and comprised of inferior frontal gyrus and temporal parietal junction regions) have been also reported.…”

Why We Need a Developmentally Appropriate Trauma Diagnosis for Children: a 10-Year Update on Developmental Trauma Disorder

“…The third DTD domain, self and interpersonal dysregulation (Criterion D), has six symptoms that represent problems with self-concept and in relationships. Severe self-ideal discrepancies (Mason et al, 2019;Schweizer et al, 2020), and associated alterations in brain network connectivity (Lanius et al, 2020), are operationalized as a view of oneself as irreparably damaged and defective (Herman, 1992). Dysregulation in relationships takes several forms, including avoidant and aggressive modes of relational engagement and social information processing (McLaughlin et al, 2020;Schweizer et al, 2020), expectancy of betrayal (Choi & Kangas, 2020;Gagnon et al, 2016), disorganized attachment and rejection sensitivity (Foxhall et al, 2019;Snyder et al, 2019), enmeshed or permeable/dependent psychological boundaries (Geanellos, 2003;Kerig, 2005;Shaffer & Sroufe, 2005;Stiles, 2004;Stiles & Raney, 2004), and excessive or deficient empathy (Chen et al, 2021;Espejo-Siles et al, 2020;Malti et al, 2010).…”