Hey, I’m doing yet another new thing. Writing study summaries for a site called SciWorthy to get some Trauma talk in the scientific learners circle.

Below, find my first submission… before I had to cut it down by 50%. Enjoy a review of a review on rumination and the correlation to PTSD!

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Article: Rumination in posttraumatic stress disorder: A systematic review

Michelle L. Moulds, Madelyne A. Bisby, Jennifer Wild, Richard A. Bryant

Headline

Chronically trapped in your own negative thoughts? Traumatic events could be the cause of your rumination.

Subheading

Post-traumatic Stress Disorder (PTSD) is linked with a penchant for unshakable negative inner dialogues and intrusive thought patterns that just won’t quit. Which comes first, the obsessive thoughts or the Trauma symptoms?

Introduction

Psychologists from The School of Psychology at The University of New South Wales, and The Department of Experimental Psychology, University of Oxford recently conducted a systematic review of the empirical literature in both 2019 and 2020 based on peer-reviewed studies including both symptoms of rumination and PTSD. As any mental health professional with a trauma informed practice can tell you, the conditions are anecdotally linked, but largely unstudied in a formal research setting.

Rumination is a continuous and penetrating thinking pattern which includes repeated, dysfunctional dwelling on a single thought or group of thoughts which are generally based on past experiences that cause distress to the thinker. The thought pattern has been proven to be a common feature of depression. It has been studied in the context of clinical and acute depression, but rarely examined in connection with other mental health disorders. However, today rumination is known to be intricately linked with other diagnoses, including post-traumatic stress disorder (PTSD).

PTSD is an often-misunderstood condition created after the brain incorrectly files away new memories which are too difficult to process at the time of occurrence. In other words, the new experience is so far outside the realm of the subject’s understanding that the event is “set aside” to be fully processed at a different time. Unfortunately, these fragmented thoughts and memories can re-emerge at unideal times, causing great mental distress to the traumatized subject in the forms of emotional outbursts, unpleasant and realistic memory provocations, and uncontrollable intrusive thoughts.

While instances of acute violence and chaos are often accepted as PTSD-inducing, there are many less dramatic experiences that can be classified as “Trauma.” Our understanding of the mental health disorder has been largely limited to battlefield PTSD and research of the ongoing mental health symptoms has only recently been expanding to new areas. As one of the hallmarks of PTSD, ruminating thoughts should be further examined to understand the establishing and maintaining effects of persevering thinking patterns in enduring trauma states.

Rumination can be a detriment to healthy living in the context of interrupting applicable and relevant thinking, inhibiting healthy sleep patterns, and causing appetite disruptions, along with other basic life functions. This obsessive thinking is different from worry, in the sense that worrying involves future events while rumination is largely linked to past or present experiences. Although catastrophic forward-thinking is also closely partnered with PTSD, historic rumination processes are hypothesized to strengthen or maintain characteristics of post-traumatic dysfunction.

Authors of the review in question remark on this link between intrusive thoughts and mental disorders, clarifying that they are largely interested in the instances of rumination regarding the subject’s trauma, in particular. Whereas one can ruminate on any subject, there is a correlation between PTSD and intrusive thoughts about the subject’s traumatic experience or the psychological aftermath of the experience (i.e. “Why didn’t I…?” or “What if I’m like this forever?”). This is accompanied by an emphasis on the ways the subject, themselves, could be to blame.

In this way, it is believed that the experience of ruminating is both causative and effective in relation to enduring PTSD symptoms. Subjects attempt to understand their trauma through perseverant thinking about the causes and consequences of the event, but in doing so, they suffer through obsessive thought patterns that may maintain their mental distress rather than causing it to subside. This complicated and unproductive relationship was the intended target in the present literature review.

Methods

To conduct their review, researchers compiled 809 published journal articles including variants of the phrases, “PTSD” and “rumination.” These publications were then filtered to include only those fitting increasingly strict conditions, including clinical samples and at least one established measure to indicate rumination and PTSD symptoms were present. In the end, 40 studies were included in this literature review for summarization and analysis.

From those 40 studies, researchers examined the key findings of the studies and specifically addressed six major questions, including: What is the correlation in frequency between rumination and PTSD? Are rumination and PTSD related cross-sectionally? Does rumination predict PTSD? Are other processes related to rumination in PTSD? Are there shared neurobiological conditions between the two? And does treating PTSD affect prevalence of rumination?

Results

What is the correlation in frequency between rumination and PTSD?

Across studies, researchers found a strong connection between the occurrence of rumination and PTSD diagnoses. Compared to non-traumatized controls, there was a positive correlation between tendency for rumination and prior traumatic experiences – with an even stronger link between rumination and participants who exhibited signs of PTSD following their trauma. One study even found a reported rate of obsessive, intrusive thoughts as high as 82% in war veterans with PTSD.

Most interestingly, the subjects who received post-traumatic stress disorder diagnoses had ruminating thoughts which were characterized ways that otherwise differed from control groups, including having a persevering focus on their trauma-event, depressive rumination, and pre-sleep rumination. Subjects with PTSD also reported in one study that they experienced rumination which included other sensory stimuli beyond verbal thoughts, including sights, smells, and sensations.

Furthermore, another study reported that PTSD sufferers indicated that rumination was an involuntary behavior. In this case, their intrusive thoughts were not purposely being utilized with the intention of resolving their past trauma experience. Not only was the rumination an automatic process, but it had the unfortunate effect of exacerbating their negative recollections, difficult emotional processes, and self-evaluations. Rumination triggered additional rumination and strengthened their negative experiences.

Are rumination and PTSD related cross-sectionally?

In multiple studies, researchers found a relationship between the severity of PTSD symptoms and occurrence of rumination, indicating that these are common features for trauma patients at a given point in time. The types of perseverant thinking that were presented by PTSD sufferers included intrusive trauma memories, depressive rumination, self-focused rumination, rumination as an emotion regulation strategy, and the general tendency to ruminate.

These findings, along with others, caused reviewers to question whether it is the content of the rumination or the specific features of the rumination that strengthens PTSD symptoms to reach clinical levels. For instance, asking “What if” or “Why” questions and having unproductive repetitive thoughts were connected with a tendency for persistent rumination and PTSD symptom presentation 6 months after the initial questionnaire. These studies indicate that it is the mode of processing that determines the usefulness or danger of rumination in the context of PTSD.

Does rumination predict PTSD persistence over time?

Authors of the present review found that early instances of rumination soon after a traumatic event were linked to development of persistent PTSD symptoms which spanned extended periods of time. In other words, obsessive thoughts about the person or the event were likely to lead to the development of PTSD. Many studies showed that reporting rumination 2-4 weeks after the occurrence was a consistent predictor of post-traumatic stress disorder anywhere from 6-months to 24-months after the initial event. This indicates that there is a connection between occurrence of intrusive thoughts and the emergence of PTSD at a later time.

The most interesting part of their findings is the connection between rumination before a traumatic event and onset of PTSD symptoms. Apparently, being predisposed to repetitive, obsessive thoughts, itself, is a predictor of post-traumatic stress disorder. This correlation highlights the importance of tackling rumination as a key to treating PTSD, not only as a side-effect of the disorder.

Are other processes related to rumination in PTSD?

Researchers were curious if rumination works as a predictor or co-morbidity of other mental health disorders or conditions besides PTSD. After reviewing relevant works, they found that obsessive thoughts are unsurprisingly linked with poor attention control, reduced heart rate response during traumatic event recollection, and depression. Researchers found further indications of a correlation between rumination and poor emotional control, as well as undetailed autobiographical recall. It is unclear in most instances if rumination mediated the onset of these secondary conditions which are associated with PTSD, or if they are all symptomatic of PTSD. The ways that rumination intermingles with other psychological processes to cause or strengthen them is a target for further study.

Are there shared neurobiological conditions between rumination and PTSD?

Researchers were curious if there are similar brain mechanisms at work that cause both rumination and PTSD, or if the two processes are coincidentally or causatively linked. One study found that the orbitofrontal cortex (OFC) shows increased activity in females with PTSD who have indicated that they experience trait rumination. This part of the brain is responsible for making decisions based on sensory input, such as inhibiting emotions, causing fear-based behaviors, and processing negative information. Activity of the OFC in this circumstance indicates inefficient emotional control in those affected.

The roles of several additional areas of the brain have been indicated in understanding the relationship between PTSD symptoms and rumination. The brain regions involved in decision making, emotional regulation, and cognitive control seem to be compromised with extreme high or low activity in patients with PTSD. Further research is needed to determine the extent of involvement of these shared brain processes.

Does treating PTSD affect prevalence of rumination?

Research is severely lacking in studies examining the treatment of rumination as a means to improve PTSD symptoms and vice versa. In one study, researchers showed that studying participants who had experienced traumatic car crashes showed a decrease in all PTSD symptoms over time using written exposure therapy. At the 3-month mark following the accident, rumination had decreased alongside other trauma symptoms. This single study shows that there may be connections between treating both conditions, however, it does not accurately indicate any relationship between treating rumination as a means to decrease other PTSD symptoms.

Conclusions

In this review, researchers from the Psychology departments of The University of New South Wales and Oxford set out to determine if there was a relationship between rumination and PTSD symptoms based on the findings of 40 peer-reviewed publications. The results pointed towards a positive correlation between post-traumatic stress disorder and ruminatory thinking patterns, along with several other mental health conditions which are implicated in both, including attention-deficit disorder, depression, and obsessive compulsions.

Unfortunately, it has not been fully elucidated if rumination is a predisposing factor for the development of PTSD or vice-versa, outside of the single study which showed that rumination preceding a traumatic event correlates with a higher instance of PTSD symptoms down the road. There is a great deal of research which still needs to be done to better understand the common comorbidities of depression, rumination, and PTSD, and the interrelatedness of all three. At this point it is unclear if rumination maintains or establishes PTSD symptoms and depression, or if the relationships are more complicated than a singular cause-and-effect.

The initial studies detailed by Moulds, et al. seem to indicate that it may be possible to treat one disorder to improve the others, but a great deal of additional research is needed to verify that this therapeutic process is effective. Furthermore, it’s necessary to perform more probing studies into the physiology and neurobiology underlying PTSD, rumination, and other associated conditions. There are greater implications for multi-dimensional treatment options if these processes are shown to be controlled by the same neurobiological mechanisms.

As anyone who has suffered from PTSD, rumination, depression, obsession, and other mental health disturbances knows, the interconnected relationships between these conditions is difficult to understand. On an individual level, it’s nearly impossible to differentiate between experiences with one from the next, and there is often an escalating effect among mental health disorders. It will be immensely powerful for practitioners and clients, alike, should more research emerge to delineate the tangled connections between PTSD, depression, and intrusive thoughts.