Inflammation in the Body, a Possible Link to "Out-of-Body" Experiences

A recent study, currently undergoing peer review, suggests that inflammation in the body may play a role in the onset of dissociation — a mental state that includes out-of-body experiences and the feeling that the surrounding world is not real. According to LiveScience, researchers believe that trauma triggers a stress response which, over time, intensifies chronic inflammation in the body.

The research demonstrates a statistical correlation between inflammatory markers in the blood and symptoms of dissociative disorders, without establishing a direct causal relationship. The authors nonetheless believe that the findings warrant further investigation, and that if confirmed, anti-inflammatory medications could in future become a treatment option for people affected by prolonged periods of detachment from their own body or from reality.

"Research in this area could open an entirely new avenue for potential treatment options," said the study's lead author, Evelyn Dilkes, a psychology researcher at the University of Essex, United Kingdom.

What is dissociation

Dissociation encompasses two types of experience: depersonalisation — the feeling of being detached from one's own body, or of observing oneself from the outside — and derealisation, characterised by the impression that the surrounding world is unreal, as though it were a theatrical backdrop. According to Dr Ruth Lanius, Professor of Psychiatry at Western University in Ontario, both experiences profoundly affect one's sense of identity and perception of one's own body.

Brief episodes of dissociation are relatively common — studies indicate that between a quarter and three quarters of people experience at least one such episode during their lifetime. The phenomenon can also occur in the context of other conditions, such as schizophrenia, depression, anxiety, panic disorders, or epilepsy.

In approximately 1% of cases, symptoms persist and develop into depersonalisation-derealisation disorder (DPDR), in which those affected may live for hours, weeks, months, or years with a sense of detachment from their own body or from reality. Numerous studies have linked this disorder to traumatic experiences, such as childhood abuse or life-threatening events.

"Dissociation can provide a psychological escape when physical escape is not possible," explains Ruth Lanius, adding that the mechanism helps a person remain calm during an extremely stressful event. The problem arises when this defence mechanism persists even after the danger has passed. "Dissociation helps you survive, but after trauma it leaves you detached from both negative and positive emotions. As a result, many people lose the ability to feel fully alive," the specialist states.

The role of chronic stress and inflammation

The team led by Evelyn Dilkes began with the observation that people with dissociative disorders show changes in their inflammatory response, and put forward the hypothesis that psychological trauma may produce long-lasting biological changes. According to this theory, trauma activates the body's stress response, and if this reaction does not subside over time, the body continues to produce elevated levels of cortisol — a hormone secreted by the adrenal glands.

Cortisol normally has an anti-inflammatory effect when secreted in the short term, but prolonged exposure can promote the onset of chronic inflammation, evidenced by raised levels of blood markers such as interleukin-6 and C-reactive protein.

To test the hypothesis, the researchers analysed biological samples from the Avon Longitudinal Study of Parents and Children, which has been conducted in the United Kingdom since the 1990s. Participants had blood samples taken at the ages of 9, 12, 17, and 24, and in adulthood were asked about dissociative experiences, including the feeling of not being a real person or the impression that the surrounding world seems unreal.

Preliminary results showed that elevated interleukin-6 levels at age 9 appear to be associated with the emergence of depersonalisation symptoms in adulthood. By contrast, elevated C-reactive protein levels in childhood, followed by lower values in adulthood, were correlated with derealisation.

The authors suggest that prolonged exposure to stress may alter the immune system's response over time, which would explain why the levels of certain inflammatory markers can decline even as symptoms continue. The researchers also believe that interleukin-6 and C-reactive protein may influence different brain regions, responsible for depersonalisation and derealisation respectively. "This suggests the existence of an extremely complex system," states Evelyn Dilkes.

What is known about brain mechanisms

The current study cannot pinpoint exactly which brain regions are affected, but previous research offers some explanations. According to Ruth Lanius, dissociation appears to be associated with a diminished emotional response at the cerebral level: the prefrontal cortex, responsible for planning and decision-making, inhibits the activity of the limbic system, which is involved in emotional processing. According to this theory, circuits in the amygdala — the region involved in processing fear — excessively activate the prefrontal cortex, which then reduces the activity of the limbic system, leading to a diminished intensity of emotions.

This model differs from that seen in the classical form of post-traumatic stress disorder (PTSD), where the amygdala is hyperactive and certain regions of the prefrontal cortex are less active, although a dissociative subtype of PTSD also exists. Other preliminary studies suggest the involvement of the default mode network and the temporoparietal junction, structures considered essential for maintaining one's sense of personal identity.

The authors of the new study put forward the hypothesis that exposure to elevated levels of interleukin-6 in childhood may influence the development of these neural networks and, consequently, the emergence of depersonalisation symptoms in adulthood.

Limitations of the research

Independent specialists caution that the results must be interpreted carefully. Judith K. Daniels, Professor of Clinical Psychology at the University of Groningen, points out that people with dissociative disorders form an extremely heterogeneous group, and that the underlying biological mechanisms may differ depending on the cause of the condition.

Furthermore, the inflammatory markers analysed are non-specific and may be elevated in numerous other inflammatory and autoimmune diseases, such as rheumatoid arthritis, lupus, or multiple sclerosis. Additionally, the majority of people who undergo traumatic experiences do not develop dissociative disorders, which indicates that other factors are involved, including genetic predisposition or environmental influences. For this reason, inflammatory markers cannot currently be used to diagnose depersonalisation-derealisation disorder, although in future they could complement existing clinical assessment methods.

Another limitation is that neuroscience does not yet fully understand how the brain constructs the conscious perception of reality. "In my view, if we do not understand altered states of consciousness and dissociation, we cannot fully understand psychopathology," says Ruth Lanius. Experts emphasise that further research is needed to establish whether reducing inflammation could become an effective treatment strategy.

Although considered rare, depersonalisation-derealisation disorder is, according to specialists, frequently underdiagnosed, because many patients are unable to describe what they are experiencing or are not correctly identified in clinical practice. "So many people are struggling with this, but nobody has the right words or the knowledge to describe it," concludes Evelyn Dilkes.