As a psychotherapist, I am sometimes asked, “What does it say about my brain if I experience depersonalisation, derealisation or another severe form of dissociation?” Brain function and imaging is beyond my expertise, so I am writing this post partly to learn. Some of the content was generated using AI and edited by me.
Here I look at a 2022 brain-imaging study by Lauren Lebois and colleagues and ask what it can tell us about dissociation and brain connectivity. It is an introduction to the research, not an authoritative account of the neuroscience.
If you are looking for psychotherapy rather than research, you can read more about my work with trauma and dissociation.
The study
The study included 91 adult women with varying levels of trauma exposure, PTSD and dissociation. Some had PTSD, the dissociative subtype of PTSD or dissociative identity disorder (DID); others were non-psychiatric controls. Participants underwent resting-state functional MRI (fMRI), an indirect measure of brain activity while someone is not doing a particular task. [1]
What researchers mean by brain connectivity
The researchers focused on three large-scale brain networks: the central executive network, linked with attention and cognitive control; the default network, linked with internally directed thought and autobiographical memory; and the salience network, involved in noticing important information.
Two brain areas have stronger functional connectivity when their activity rises and falls together more closely over time. This is a statistical relationship. It does not mean that the areas are directly wired together or that one is causing the other to act. [1]
What did the study find?
After accounting statistically for age, childhood maltreatment severity and PTSD symptom severity, dissociation was associated with altered connectivity in all three networks. The right central executive network contained the greatest number of brain areas where connectivity varied with dissociation. In other words, it showed the largest number of measurable connectivity differences associated with higher dissociation. [1]
The researchers also examined depersonalisation/derealisation, “partially-dissociated intrusions” and DID separately, and reported somewhat different patterns for each.
Why a “brain fingerprint” is premature
The authors describe their findings as beginning to identify a brain-connectivity “fingerprint” for different forms of dissociation. That is an interesting possibility, but the study does not establish a validated fingerprint.
The research was cross-sectional: participants were assessed at one period in time. It therefore cannot tell us whether connectivity differences cause dissociation, result from it, reflect previous trauma or treatment, or arise in some other way.
The three dissociation measures were also highly correlated. The initial analyses corrected statistically for the fact that many comparisons were being made. The later analyses looking for differences unique to each subtype did not. This made the analysis more likely to pick up possible real effects (increased sensitivity), but also increased the chance of chance findings.
Other researchers therefore need to find the same subtype patterns in new groups before we can be confident they are reliable (independent replication). [1]
Systematic reviews suggest that dissociation is associated with differences across distributed brain systems rather than one single “dissociation centre”, but findings remain varied. [2,3]
A 2026 review of DID neuroimaging also highlighted another difficulty. Brain regions usually have many functions. Suppose, for example, that researchers find altered connectivity in an area known to be involved in thinking about ourselves. That does not prove that altered self-processing is what produced the person’s dissociative experience. Drawing a conclusion about a particular mental process simply from the brain area involved is called reverse inference. [4]
What might this mean for people experiencing severe dissociation?
For my clients, the immediate clinical meaning is limited. A brain scan cannot currently diagnose dissociation or DID, explain why one person developed their symptoms, reveal their trauma history or tell us which psychotherapy will work best.
The longer-term possibilities are more interesting. If reliable patterns are eventually found, brain research might help clinicians distinguish forms of dissociation more precisely, understand differences in treatment response, or identify biological changes that accompany recovery.
It might also help us compare what people describe feeling and experiencing with changes that can be measured in the brain. That could add another perspective on dissociation without suggesting that the scan itself contains or fully explains the person’s experience.
The broader idea that dissociation can function as an adaptive response to overwhelming experience is influential and widely accepted in trauma-focused clinical thinking, although its mechanisms remain debated. [1,5] But this study does not establish that these particular network changes are adaptive responses to childhood trauma, or that they produce particular dissociative experiences.
What can we conclude?
For now, the strongest conclusion is modest. Neuroimaging is beginning to identify biological correlates of dissociation: measurable brain characteristics that vary alongside dissociative experience. A correlate is not necessarily a cause.
The research gives us another way of studying severe dissociation, but not yet a way of reading an individual person’s experience from their brain.
References
1. Lebois, L.A.M. et al. (2022). Deconstructing dissociation: a triple network model of trauma-related dissociation and its subtypes. Neuropsychopharmacology, 47, 2261–2270. DOI: 10.1038/s41386-022-01468-1.
2. Lotfinia, S., Soorgi, Z., Mertens, Y. & Daniels, J. (2020). Structural and functional brain alterations in psychiatric patients with dissociative experiences: A systematic review of magnetic resonance imaging studies. Journal of Psychiatric Research, 128, 5–15. DOI: 10.1016/j.jpsychires.2020.05.006.
3. Roydeva, M.I. & Reinders, A.A.T.S. (2021). Biomarkers of Pathological Dissociation: A Systematic Review. Neuroscience & Biobehavioral Reviews, 123, 120–202. DOI: 10.1016/j.neubiorev.2020.11.019.
4. Schlesselmann, A. et al. (2026). A critical review of methodological quality in functional neuroimaging studies on dissociative identity disorder. Memory, 34, 113–127. DOI: 10.1080/09658211.2025.2587233.
5. Krause-Utz, A. et al. (2017). Dissociation and Alterations in Brain Function and Structure: Implications for Borderline Personality Disorder. Current Psychiatry Reports, 19, 6. DOI: 10.1007/s11920-017-0757-y.