When PTSD Walks Down the Hall

Here’s how to catch a PTSD chameleon using DSM-5 criteria.

Many confident psychiatrists have quipped, “I can recognize posttraumatic stress disorder (PTSD) as it walks down the hall.” It may be an exaggeration, but it does belie a surprising truth about the disorder. Even without knowing that someone has been traumatized, PTSD is recognizable.

PTSD is a constellation of maladaptive changes that can occur after an extreme stressor, though it does not happen to everyone who is traumatized.1 When it occurs, it involves disturbing experiences, such as flashbacks to the trauma and potentially long-term alterations to patterns of thinking, behavior, and biology. 

While these changes have long been described, our current conceptualization of PTSD was identified as shell shock in 1915 by World War I soldiers. It described the experience of fatigue, tremor, confusion, nightmares, and impaired sight and hearing among soldiers recovering from battle.2 The definition of shell shock has changed over the years to include different categories of traumas, such as sexual trauma and indirect trauma. And while PTSD used to be considered an anxiety disorder, it is now just one among a separate group of trauma- and stressor-telated disorders in the DSM-5.

Making the initial diagnosis of PTSD can be challenging, as PTSD symptomology runs the gamut of phenomenology described in the DSM-5. PTSD can both resemble and commonly co-occur with a broad range of other psychiatric conditions.3 Dissociative experiences such as flashbacks can strongly resemble hallucinations. Perfectionism may present as obsessive-compulsive disorder (OCD). Dramatic mood swings may be difficult to differentiate from bipolar disorder. Concurrent substance abuse issues are also quite common, not to mention the changes in cognition and sense of self that mimic several different personality disorders. The list of doppelganger or complicating diagnoses that may accompany PTSD includes nearly every other diagnosis listed in DSM-5.

So then, what does PTSD look like when it walks down the hall? How can clinicians recognize PTSD even if the patient is in denial of their trauma? And how can a clinician conduct the interview on this sensitive topic without retraumatizing the patient in the process?

Walking Through PTSD

Not every patient with PTSD will experience every symptom of the disorder. In fact, it is not atypical for patients to display the opposite of some symptoms. What is typical of PTSD is that there is no middle ground. There is an all-or-nothing quality to these changes. As a model of nonrecovery after trauma, each may be conceptualized as either an over- or under-compensation.

DSM-5 lists 5 criteria for diagnosing PTSD,4 but the order in which they are presented is almost precisely backward from how they will present during a session. Unless you happen to work in a PTSD clinic, where every patient is presumed to have experienced a trauma, you will not necessarily know this from the start. So, let us review the criteria in reverse order.

Criterion E: Alterations in Arousal and Reactivity

In particularly severe cases of heightened arousal or hypervigilance, the patient may refuse to walk down the hall ahead of you. They simply cannot abide anyone walking behind them. You may gesture for them to go ahead of you, and they will instead gesture for you to go ahead of them. It creates an unmistakably awkward moment. Others may handle the hallways just fine but then refuse to go into the office before you.

In the work of telehealth, this behavior is more subtle. If you are not present when the patient logs on, they may panic and call the office, convinced they did something wrong or that they will be billed a no-show fee. Of course, all patients may do this after a long wait, but patients with PTSD tend to do this after a surprisingly short amount of time, even if they have been asked to wait.

Patient with PTSD may point out flaws that exist in your paperwork, scheduling, or front-office operations. While most patients try to make a good impression, a patient with PTSD may put you on the defensive. Or, they might not show up at all.

This heightened arousal and reactivity has a neurobiological basis. The hypothalamic-pituitary-adrenal system (HPA axis) and the sympathetic nervous system have long been known to regulate the stress response. Both are activated acutely during or after the trauma, but their sensitivity or reactivity to stress also increases over the long term, even after the stressful event has ended.5

The details of these long-term changes to the HPA axis and the sympathetic nervous system have yet to be fully mapped. However, both systems in PTSD patients appear to lack or have lost calming influences. For instance, the stress hormone cortisol, though elevated during acute stress, has also been shown to help patients process their traumatic memories afterward.6,7 Yet it is chronically low in patients with PTSD. Whether this is a cause or the result of PTSD is still unclear. While the sympathetic nervous system is typically implicated in the short-term fear response, it appears to lose inhibitory input over the long term, making the fight-or-flight mode easier to access.5

Signs of heightened arousal may pervade the clinical picture in patients with PTSD even beyond the formal criteria. Patients with PTSD almost invariably have trouble sleeping. Studies of comorbidities often find high associations with both sedative and stimulant abuse.8

Criterion D: Negative Alterations in Cognitions and Mood

There are 2 themes at work with this criterion: extremes in thinking, and numbing or avoidance. Though the biology of these changes is still not well understood, numbing symptoms can be thought of as being on a continuum with dissociation, a more severe form of detachment from reality.9,10 In these criteria, numbing is distinct from avoidance, which is discussed further in Criterion C. Patients may also have trouble with memory and attention, and high comorbidity between PTSD and attention-deficit/hyperactivity disorder can make these diagnoses difficult to tease apart.11

In extreme cases of dissociation, symptoms may be chronic or may include depersonalization or derealization. Depersonalization is when patients feel they are detached from their body, such as an out-of-body experience. Derealization is the sense that they are not in the real world, as if this world is a fake.

The negative cognitions of Criterion D often involve absolutes in the realms of self-esteem, trust, danger, and intimacy. Again, what is missing is the middle ground. A useful paradigm is the just-world belief, a concept used in cognitive processing therapy to understand the cognitive changes of PTSD.12 According to the just-world belief, good things happen to good people and bad things happen to bad people. Over time, it is normal to realize that these concepts, while often true, have their limitations. Reality is more nuanced. Good things sometimes happen to bad people, and bad things sometimes happen to good people.12

In a normal response to trauma, the victim will cope by amending their worldview to account for the trauma without losing their sense of control. They will find the middle ground. An individual with PTSD, however, will either rigidly cling to the just-world belief or discard it altogether. If they cling to it, they may blame themselves for what happened. They may respond by developing low self-esteem or perfectionistic tendencies to prevent trauma from happening again.12 These can be so extreme as to overlap with the symptoms of OCD.

On the other hand, if they reject the just-world hypothesis entirely, they may conclude that the world is a dangerous place and they are powerless to prevent negative events in the future. These patients may become reclusive and experience difficulties opening up or trusting others. Their beliefs can be applied in myriad ways, even to some areas of life but not others.12

Preexisting anxiety disorders, genetic susceptibility, religious beliefs, circumstances, and many other factors may influence the direction a patient goes with their just-world belief. In generational trauma, where multiple generations experience similar trauma, parents may pass down their extreme version of the just-world belief. For instance, a mother may teach her daughter that all men are dangerous and she should always be on guard around them. This can create familial patterns in which ways of coping with trauma are uniform and considered normal.

To a pateint with PTSD, these beliefs are not distorted. They are truths learned the hard way, and they can provide protection after trauma. As such, clinicians should treat these with extreme delicacy. Even if patients are able to recognize their belief is a product of their trauma, a clinician’s focus at this initial stage should be providing education and not changing beliefs.

To a patient with PTSD, these beliefs are not distorted. They are truths learned the hard way, and they can provide protection after trauma.

It is common knowledge that victims of trauma should not be blamed for what happened to them. It can even be helpful to reassure them that they are not at fault. However, do not push this point. You may be surprised to find that some patients will cling to their guilt, and there is a valid reason for this. In some, guilt is easier to tolerate than helplessness and vulnerability. The implication of self-blame is that they had some control over what happened. As long as they make different choices in the future, the trauma will not repeat. But the realization that they were actually powerless during their trauma implies the trauma could happen again at any moment. While these self-blaming beliefs are certainly not the end goal of treatment, they can be addressed more effectively later.13

Criterion C: Persistent Avoidance of Stimuli Associated With the Traumatic Event

Eventually, clinicians may notice that something is conspicuously absent from the patient’s interview: a history of trauma. This is likely because the patient is avoiding the topic. Distinct from the dissociation described in Criterion D, this avoidance is more deliberately focused on the traumatic event itself.

Patients with PTSD avoid talking about, remembering, or even feeling the feelings associated with the trauma for good reason: it may trigger a flashback. A patient with PTSD may be stuck in a conundrum: how can they reveal their trauma without bringing up any associated thoughts, feelings, or memories?

Along with numbing, avoidance is a critical diagnostic feature of PTSD.14 Avoidance may present as forgetting critical aspects of the traumatic event, forgetting the event altogether, and avoiding downtime by staying busy. Downtime is when memories usually bubble up, so they may avoid discussing the traumatic memory or going to bed for fear of nightmares. They may also avoid individuals or places associated with the trauma or anything that reminds them of it. These reminders can take any form and, tragically, may be generalized to an entire demographic group, blurring the line between PTSD and concepts such as racism.

Avoidance, whether through willpower or dissociative amnesia, and how it is accomplished is quite varied in style and intensity. In talking with the clinician, some patients may simply pretend the event did not happen or convince themselves their experience was normal. Others will stay talkative in session to prevent the topic from coming up; others may lead with anger, using statements such as, “People like you can’t understand” to disempower the provider and discourage them from asking invasive questions.

When asked to identify when symptoms started, some patients will openly reveal their trauma. Others will deflect. Let them. This avoidance protects them, as well as the interview, from being waylaid by flashbacks. Instead, invite the patient to start at the beginning and collect their history longitudinally. This has many benefits. For one, it is easier to open up to someone who knows you, and learning about someone’s childhood helps them feel known. This also has the benefit of redirecting the narrative toward a potentially pretrauma part of their life.

As memories are linked to emotions, discussing what happened before their trauma can have a calming effect.15 With the exception of early childhood trauma, childhood memories are not laced with the heightened emotionality and rigid thinking patterns developed after the trauma. Giving patients an opportunity to describe what led up to their trauma gives them a chance to explain why and when it happened, thus making the story more understandable. Further, a longitudinal history gives clinicians valuable diagnostic information and potential tools for comforting the patient if/when they do become triggered. Diagnostically, one of the only ways to tease apart PTSD from other potentially co-occurring disorders mentioned earlier is to assemble them on a timeline.16

Knowing what came first and whether problems developed simultaneously or at different times are crucial questions for determining which problems are primary or secondary.16 Similarly, it is critical for determining which problems predated their trauma and how they changed through critical life events. If symptoms of PTSD began relatively simultaneously at a certain point in life, trauma likely occurred during that time.

Finally, delving into childhood gives clinicians a sense of a patient’s earliest strengths and vulnerabilities in their own words. This can be drawn upon when a patient later feels exposed. Ask how they coped with hardship in childhood. How did they perform in school socially and academically? If they did well, ask why. Were they highly motivated or just smart? Did someone push them? If they had any struggles, ask them about their strengths and how they adapted.

Understanding their basic coping skills may give you insight into how they coped with their traumatic event. You may be able to point out how their strengths, whether innate or learned, helped them survive their trauma. Giving strength-based feedback that is based on the patient’s history and in their own words can help soften the landing, so to speak, after their trauma is revealed.

Criterion B: The Presence of Intrusion Symptoms Associated With the Traumatic Event

Eventually, a clinician may ask, “Is there a chance anything traumatic happened around that time?” This question, or the answer to it, can bring forth a patient’s intrusion symptoms, which are memories that have been preserved in their original, terrifying state. It is essential to recognize these immediately and help patients extinguish the experience if it happens in the office.

Classic intrusion symptoms, known as flashbacks, are essentially raw memories that have not been processed normally into long-term memories. The amygdala is the part of the brain believed to be responsible for the formation of fear memories and their retrieval as flashbacks. It works in close association with the hippocampus. The amygdala is like a jumpy, overprotective cave-person living inside your brain, determined to keep you alive in a dangerous world. It reviews all external and internal sensory data for signs of danger and stimulates immediate reaction. After information comes in, the amygdala flags the most fearful memories for the hippocampus to remember in detail.17

A part of the higher-order cortical regions of the brain, the medial prefrontal cortex (mPFC), is less active in patients with PTSD. It is highly associated with working memory. This region is critical because it normally has an inhibitory, or calming, effect on the amygdala. It also stimulates the normal processing of traumatic memories after the event has passed.6,7 This memory processing allows for memories to fade with time or be reprocessed into less disturbing, more manageable states.18 For instance, normal memories lose much of the sensory information that was associated with them as they fade into the past.

The mPFC is responsible for the recall of the trauma events in patients who do not have PTSD, but it is not as active in patients with PTSD. Memory retrieval is therefore managed by the amygdala instead. Perhaps due to the primitive nature of this part of the brain that evolved before the neocortex, the amygdala is not concerned with the concept of time. Thus, memories that are managed primarily by the amygdala are frozen in time.6

During a flashback, a patient with PTSD experiences their traumatic memory as if it were happening right at that moment. These unprocessed memories remain linked with all the sensory and physiological data that was encoded by the hippocampus during the original trauma. The amygdala does not bring back the concept of the experience, it retrieves and restimulates the actual emotional and physiological experience.6 Without a sense of time, the amygdala processes data from this flashback along with the new triggering event as a single traumatic event. 

In response to the trauma, whether original or reexperienced, the amygdala will directly activate the HPA axis and the autonomic nervous system, generally setting the ball in motion for the physiological changes of PTSD. Furthermore, in combination with other parts of the limbic system, the amygdala can sense and react to sensory information without involving the neocortex. In other words, a patient with PTSD can have a flashback triggered by something in the environment or a sensation in their body, which they did not even consciously notice.17

Intrusion symptoms do not just bother patients, they haunt them. Flashbacks refer to the complete sensory phenomenon of reliving the experience. Nightmares replay the trauma. Intrusive memories are partially processed memories that pop up randomly, but do not bring the full sensory experience. Somatic flashbacks occur when the sensory aspects of the trauma appear without conscious awareness of the memory. In patients with complex PTSD, their ability to dissociate from the trauma may be so swift and complete that they are not aware of the flashback. Instead, they go straight into the numbing and detachment that masks it.

Red flags that your patient is having a flashback include changes in their speech, voice, and demeanor; rapid breathing; and perspiration. They may stop talking and look away, start rocking or mumbling to themselves, or look scared or suddenly angry.

If this happens, it is imperative to give them a path out. Ask if they are having a flashback. They may not answer. Unless their answer is a clear no, then continue to ask, “Can I help you get out of it?” You still may not get an answer. But always ask permission before telling a patient what to do, especially a trauma patient. Never attempt to touch or approach a patient having a flashback. They may experience this as threatening and respond in unexpected ways. Do not ask them for details, as that will only deepen their experience and feelings. Instead, stay calm and ask them to count something in the room, such as windows or picture frames. Do not accept vague answers like “a few.” Teaching them this grounding exercise will help them transition their attention away from emotional historical content to logical nonemotional content.

Once calm and able to discuss what happened, warn patients that talking about their trauma can lead to flashbacks that can worsen their symptoms. Offer patients a path through their story that involves minimal details. This is akin to tiptoeing around the story, giving you just enough information to finalize a diagnosis. If they get lost, gently prompt them to describe how they survived their trauma. This may help them end their story on a note of strength.

Criterion A: Exposure to Actual or Threatened Death, Serious Injury, or Sexual Violence

At this point, if the patient has clearly met Criteria B through E, documenting Criterion A can seem more like a formality.14 Yet, the existence of a Criterion A trauma is necessary for the diagnosis of PTSD. But what counts? Discussions between psychiatrist and patient that question the validity of the experienced trauma are likely to increase a sense of victimization and mistrust. This part of the conversation must be handled delicately and with a firm understanding of what types of stressors meet the criteria.

In 2013, the criteria for diagnosing PTSD were updated with the publication of the DSM-5. It both expanded (by including sexual violence) and narrowed the definition of a qualifying event for Criteria A (by excluding threats to “physical integrity.”) These changes succeeded in clarifying the diagnosis, which was hailed as beneficial to research efforts.14 Yet, they are not as helpful for clinicians who are treating patients in the field.19 There are obvious gaps in this definition of trauma that include, but are not limited to, brainwashing, emotional abuse, homelessness, and delusions or hallucinations of a life-threatening nature.20 Furthermore, the question of whether a global pandemic can be a Criterion A event—and under what circumstances—is yet to be clarified.

In 2014, prior to the COVID-19 pandemic, a survey of more than 23,000 individuals in 13 countries examined the implications of the DSM-5 and the International Classification of Diseases (ICD-11) criteria as compared to the criteria in DSM-4 and ICD-10. Patients who met the criteria for PTSD according to a “broad” diagnostic approach had symptoms that were no less severe than patients who met criteria under a “narrow” range of applicable standards.21

Concluding Thoughts

It is clear that trauma does not have to be directly experienced by the patient to result in PTSD. Learning of trauma to loved ones, even indirectly, can trigger it. So can the direct exposure to the trauma of strangers, as is the case of first-responders. Repetition of traumas can also raise the likelihood of developing symptoms.19 But learning about tragedies that happen to strangers via electronic media, has not been considered a Criterion A stressor.22 One must wonder whether media reports about a life-threatening global pandemic might create conditions where PTSD could develop. What if that news is directly linked to dramatic life changes, such as the loss of a job or isolation at home? If not on its own, what about when combined with news of mass shootings, police brutality, climate change events, and other extreme threats? 

Could disturbing and personally relevant news layer to such an extent that it causes PTSD? Could this increase the likelihood of nonrecovery from more typical Criterion A stressors, increasing the frequency of PTSD even without redefining it?23 Should we also consider PTSD among those who contract COVID-19 or have family members who did?

Going forward in this interconnected, postpandemic, volatile world, it is important for clinicians to catch PTSD when it walks down the hall or logs onto a telemedicine appointment.24 Though complex, it is recognizable. In diagnosing it, we may answer the questions above and guide patients into treatment. With one of the highest rates of comorbidity with other psychiatric diagnoses, as well as one of the broadest differentials among psychiatric disorders, it is necessary to screen for PTSD in everyone seen in the outpatient setting.23

Dr Peterson LeMaster is a board-certified psychiatrist who has been with Community Psychiatry since 2016. Shereceived psychiatric training at the Department of Veterans Affairs Hospitals in Boston, through association with Boston Medical Center, including specialized training in cognitive processing therapy for PTSD in the treatment of female veterans.


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