Could Inflammation Help Explain Dissociation and Out-of-Body Experiences?

Inflammation may play a role in dissociation, a mysterious altered state of consciousness that can include out-of-body sensations and the feeling that the world is unreal, new research suggests.

Researchers have long known that trauma can trigger dissociation. Now, emerging evidence offers a possible biological explanation: traumatic experiences may activate the body’s stress response, which could contribute to long-term inflammation. The findings add to growing research into how the immune system may influence mental health.

The study has been accepted for publication but is still undergoing peer review. Because the research is based on correlations between blood markers and symptoms, it cannot prove that inflammation causes dissociation.

However, if future studies confirm that inflammation contributes to dissociative symptoms, anti-inflammatory medications or other treatments that reduce inflammation could offer a new therapeutic approach for conditions in which people feel persistently detached from themselves or reality, experts told Live Science.

“This could open up a whole new avenue for potential treatment options,” said study lead author Evelyn Dilkes, a psychology researcher at the University of Essex in England.

Dissociation Is Common, but Chronic DPDR Is Rare

Dissociation can involve two distinct experiences. Depersonalization is the feeling of being detached from your body or observing yourself from the outside. Derealization is the sensation that the world around you is unreal, dreamlike or artificial, said Dr. Ruth Lanius, a psychiatry professor at Western University in Ontario.

Short-term dissociation is relatively common. Research suggests that between one-quarter and three-quarters of people may experience it at some point. Dissociation can also occur alongside conditions such as schizophrenia, depression, anxiety, panic disorder and epilepsy.

For approximately 1% of the population, dissociation may become persistent. This condition is known as depersonalization-derealization disorder, or DPDR. People with DPDR can feel disconnected from their bodies or surroundings for hours, weeks, months or even years.

DPDR is often associated with traumatic experiences, including life-threatening events and childhood abuse. During a traumatic event, dissociation may temporarily protect a person by providing “a psychological escape when a physical escape is not possible,” Lanius told Live Science. It may also help someone remain calm and focused during an immediate threat.

The difficulty begins when dissociation continues long after the danger has ended.

“Dissociation helps you to survive, but in the aftermath of trauma, it leaves you detached from all of your emotions, positive and negative,” Lanius said. “Often, individuals lose the capacity to feel fully alive.”

Why dissociation persists in some people long after trauma remains unclear. One possibility is that the body’s stress and immune systems become biologically altered.

How Trauma May Connect Stress, Inflammation and Dissociation

Previous research has found that inflammation may be dysregulated in people with dissociative conditions. Dilkes and her colleagues investigated whether trauma-related changes in the stress response could help explain why dissociation becomes chronic.

This theory is an example of “biological embedding,” in which stressful life experiences produce lasting changes in the body. Trauma may initially activate the stress system. If that response does not settle, the body may remain in a state of heightened stress and continue releasing the hormone cortisol from the adrenal glands.

Cortisol can reduce inflammation during short periods of stress. But when cortisol remains elevated for a long time, it may contribute to chronic inflammation. This type of inflammation can be reflected in blood levels of interleukin-6, or IL-6, and C-reactive protein, or CRP.

To investigate this possibility, the researchers analyzed blood samples from children in the United Kingdom who participated in the Avon Longitudinal Study of Parents and Children. Samples were collected when participants were 9, 12, 17 and 24 years old. As adults, participants were asked whether they had ever felt that they were not real or not part of the living world, or that the world around them felt unreal or like a stage set.

The early findings suggest that higher IL-6 levels at age 9 were associated with depersonalization symptoms in adulthood. Higher CRP levels during early childhood, followed by lower CRP levels in adulthood, were associated with adult derealization.

The researchers suggest that long-term stress may eventually weaken or alter the immune response. This could help explain why CRP levels decline over time even when dissociative symptoms continue.

The researchers also proposed that IL-6 and CRP may affect different brain regions involved in depersonalization and derealization. These results could reflect the way stress and immune activity change throughout life after trauma.

Brain Networks Linked to Dissociation

The new study cannot identify which brain regions are affected by inflammation. However, earlier research suggests that dissociation involves emotional blunting. In this process, the prefrontal cortex, which supports planning and decision-making, may act as a brake on the limbic system, which helps generate emotional responses, Lanius said.

One theory is that fear-related circuits involving the amygdala overactivate the prefrontal cortex during dissociation. The heightened prefrontal activity may then interfere with normal communication with the limbic system. The result is a dampening of emotions that may help a person remain rational and focused during a frightening event.

This pattern of brain activity is often associated with DPDR and differs from the pattern typically observed in post-traumatic stress disorder, or PTSD. In classic PTSD, the amygdala is often overactive while some areas of the prefrontal cortex are underactive. However, a subtype of PTSD can also involve dissociation.

Early studies suggest that the default mode network and the temporoparietal junction may also be involved. These brain regions help maintain a sense of self, body awareness and connection to the world.

The researchers speculate that exposure to elevated IL-6 during childhood could influence the development of the default mode network, potentially contributing to depersonalization symptoms later in life. This possibility requires much more research.

Inflammation and Dissociation: Many Questions Remain

Although the findings are intriguing, outside experts cautioned that the early results should not be overinterpreted.

Comparing studies of dissociative disorders can be difficult because participants may have different diagnoses and overlapping symptoms, said Judith K. Daniels, a professor of clinical psychology at the University of Groningen in the Netherlands.

Dissociation associated with childhood abuse may have different biological features from dissociation linked to panic disorder, but current research cannot reliably distinguish between these groups.

Inflammation markers such as CRP and IL-6 are also not specific to dissociation. They can be elevated in many inflammatory and autoimmune conditions, including rheumatoid arthritis, lupus and multiple sclerosis.

In addition, most people who experience trauma do not develop a dissociative disorder. This suggests that genetic, environmental and psychological factors may also influence a person’s risk.

Because CRP and IL-6 are nonspecific biomarkers, they are unlikely to diagnose DPDR on their own. In the future, however, they might potentially be evaluated alongside established screening tools and clinical assessments.

Another major challenge is that scientists still do not fully understand how the brain creates conscious experience or constructs a sense of reality.

“If we don’t understand altered states of consciousness and dissociation, we can’t understand psychopathology fully,” Lanius said.

More research is needed to determine whether treatments that target inflammation can reduce dissociative symptoms. DPDR is considered rare, but it may be underdiagnosed because many people do not have the language or information needed to recognize their experiences.

“So many people experience this, but no one has the words or knowledge of what it is,” Dilkes said.

Editor’s Note: This article was produced as part of the Dalla Lana Fellowship in Journalism and Health Impact program at the University of Toronto.

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