Post Traumatic Stress Disorder (PTSD)

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Author: Udeni Appuhamilage, Ph.D, TMH Psychologist Udeni

Post-Traumatic Stress Disorder (PTSD henceforth) is a dysfunctional mental health condition that is triggered by a highly stressful situation or event – either by directly experiencing it, witnessing it or through indirect exposure to it via a third party (e.g., a friend, news). 

PTSD is a disorder that is defined by its causality: exposure to a traumatic event. While what counts as a traumatic event varies from person to person, some situations that are commonly identified as traumatic include auto accidents, being sexually assaulted/raped, harassment or bullying that causes extreme psychological damage including racism, sexism and many other similar abuses, experiences of violence such as in war, natural disasters, losing loved ones particularly in disturbing ways and chronic illnesses or diagnoses of life-threatening conditions. The development of PTSD depends on many factors. While some of us would survive these events with temporary difficulties and adequate coping, some others would find the initial difficulties after facing a traumatic experience to last longer, even years and the symptoms could significantly interfere with their day-to-day activities. 

Exposure to repeated trauma, lack of family/social and professional support, simultaneous exposure to multiple stressors and previous mental health difficulties can make someone more vulnerable to develop PTSD. In addition, there are certain biological explanations too, even though nothing has been scientifically confirmed yet. One such argument is that the hippocampus of people with PTSD appears smaller;[1] however, it is not clear if the smaller size is a cause or a result of trauma.

Table of Contents

PTSD Diagnosis

The fifth edition of DSM (2013, American Psychiatric Association) has two diagnoses of PTSD, for those above and below 6 years of age. It lists 6 main categories of diagnostic criteria for adults, adolescents and children older than 6 years, namely,

i) Exposure to an actual or threatened death, serious injury or violence in one or more of the following ways:

  1.     Direct experience
  2.     Witness
  3.     Learning about the traumatic event(s) happening to a close family member or friend
  4.     Work related, repeated exposure to details of traumatic event(s) (e.g., police officers)

ii) One or more of the following intrusive symptoms associated with the traumatic event(s):

  1.     Recurrent, involuntary and intrusive memories of the event(s)
  2.     Recurrent, intrusive dreams 
  3.     Dissociative reactions (e.g., flashbacks) where the person feels and/or acts as if the event(s) is recurring
  4.     Intense and prolonged psychological distress to triggers that resemble an aspect of the traumatic event(s)
  5.     Significant physiological reactions to things that resemble an aspect of the traumatic event(s)

iii) Persistent avoidance of stimuli associated with the traumatic event(s), as evidenced by:

  1.     Avoidance of memories, thoughts and feelings associated with the traumatic event(s)
  2.     Avoidance of external reminders (e.g., people, places) that arouse memories associated with the traumatic event(S)

iv) Negative change in cognition and mood associated with the traumatic event(s), as evidenced by 2 or more of the following:

  1.     Inability to remember an important aspect of the traumatic event(s)
  2.     Persistent and exaggerated negative beliefs or expectations about oneself, others or the world (e.g., ‘I am bad,’ ‘World is a completely dangerous place,’ ‘None can be trusted’)
  3.     Persistent and distorted cognitions about the cause or consequences of the traumatic event(s)
  4.     Persistent negative emotional state
  5.     Markedly diminished interest in important activities
  6.     Feelings of detachment from others
  7.     Persistent inability to experience positive emotions

v) Significant alterations in arousal associated with the traumatic event(s), as evidenced by two or more of the following:

  1.     Irritable and angry behaviour
  2.     Reckless behaviour
  3.     Hypervigilance
  4.     Exaggerated startle response
  5.     Problems with concentration
  6.     Sleep disturbance

vi) The criteria ii-v lasts more than a month.

vii) The disturbance causes clinically significant distress and/or impairment in family, social and other important areas of functioning.

viii) The disturbance is not attributable to the effects of a substance or another medical condition.

The diagnostic criteria for preschool children are developmentally sensitive and more behaviorally anchored in order to be responsive to their emerging cognitive and other capacities. Hence, some symptoms such as extreme distress at the time of the traumatic events have been removed (given this depends on one’s capacity to verbally express emotional distress) while some other symptoms are changed as is the case where only one symptom, instead of three, is required from the set of avoidant symptoms and the symptoms associated with negative changes in cognitions and mood for the diagnosis.

According to ICD-11 (2019, World Health Organisation), PTSD may develop as a result of exposure to an extremely stressful or threatening event(s).[2] ICD-11 lists three key categories of symptoms that characterise PTSD.

i) Reexperiencing the traumatic event(s) in the present (e.g., vivid and intrusive memories, flashback or nightmares) via singular or multiple sensory modalities (e.g., vision, smell, sound, etc.), leading to overwhelming emotions and physical sensations.

ii) Deliberate avoidance of thoughts and memories of the event(s), as well as activities, situations or people that remind the person of the event(s)

iii) Persistent perceptions of existing threat (e.g., hypervigilance, startle reaction to unexpected stimuli such as loud noises)

For a diagnosis, these symptoms have to last for several weeks and cause significant impairment in the person’s personal, family, social, professional and other important areas of functioning.

Complex PTSD

Complex PTSD, also known as CPTSD, can result in situations of prolonged and/or repeated trauma over months or years. The DSM 5 version does not acknowledge Complex PTSD as a separate diagnosis while ICD-11 does acknowledge it.[3] Complex PTSD is characterised by the same symptoms as PTSD; but they can be more enduring and extreme. It also has some additional symptoms.

i) A negative self-view 

ii) Significant changes in beliefs and worldview

iii) Emotional regulation difficulties

iv) Relationship issues

v) Detachment from the trauma

vi) Preoccupation with the abuser

For a diagnosis, these symptoms have to last for several weeks and cause significant impairment in the person’s personal, family, social, professional and other important areas of functioning.


One complication with PTSD is about time; while PTSD can develop immediately after experiencing a traumatic event, some people may not develop the symptoms immediately and may take months or even years to appear and to be noticed. Moreover, PTSD is closely linked with other mental health disorders such as depression, anxiety and substance abuse disorder; one can suffer from these disorders simultaneously. For instance, trouble sleeping, emotional outbursts and loss of interest in activities are common to both depression and PTSD. Anxiety is a common symptom among those with PTSD; however, PTSD highlights specific anxieties related to places, people and situations that are connected with an actual traumatic event. Many survivors of traumatic experiences seek abusive substances as a coping mechanism, and thus are vulnerable to develop unhealthy dependence on these substances. Suicide risk is another complication with PTSD that requires special attention.   

When to See a Health Professional

If you find the disturbing thoughts, behaviours and feelings related to a traumatic experience to last more than a month, if they are too intense and keep you from managing your day-to-day tasks in an effective way and if you feel that you need help with managing the situation, then, it is time to talk to a health professional – a physician, a psychiatrist, a counsellor, a psychiatric social worker or a psychologist. All these health professionals will be able to either offer you a proper assessment and treatment or to guide/refer you to the relevant professionals who will be able to help you. Getting treatment sooner is always better and can help prevent the symptoms from getting worse.


Different national bodies working on mental health service provision such as the American Psychological Association (i.e., APA), The National Institute of Health and Care Excellence (i.e., NICE) in the United Kingdom and the Australian Institute of Health and Welfare offer guidelines on how to treat and prevent PTSD. The NICE guidelines, for instance, discuss proper assessment of physical and psychological health, social needs and risks, coordinated monitoring of care, providing additional information as needed, support with transition of care, peer support, maintaining safe environments and cultural and language competence of the providers; it promotes different approaches within cognitive behavioural therapy (individual and group focused) as an effective psychological intervention for PTSD among adults and children. The national guidelines for trauma care in the Australian setting discuss both primary and secondary prevention and different approaches/interventions to stress management.

The bio-medical interventions involve prescription medications such as antidepressants, anti anxiety medications and sleep aid. Beyond the physical/bodily symptoms, PTSD is also a disorder about meaning, or the lack of it.  This is why talk therapy (e.g., cognitive behavioural therapy, eye movement desensitisation and reprocessing therapy, acceptance and commitment therapy, person centred therapy, etc.) can be a significantly effective intervention. In addition, support groups are also helpful to share difficult experiences with others with similar experiences; such sharing enables the survivors to feel a sense of belonging and collective validation. In addition, family and community support can be considerably helpful to prevent the survivor from turning to unhealthy coping mechanisms.


  1. Rubin, M., Shvil, E. Papini, S., Chhetry, B. Helpman, L., at el. 2016. Greater hippocampal volume is associated with PTSD treatment response. Psychiatry Research 252: 36-39
  2. For more information about the ICD-11 diagnosis of PTSD, please see:
  3. For more information about the ICD-11 diagnosis of cPTSD, please see: