Individual Differences in a Husband and Wife Who Developed PTSD After a Motor Vehicle Accident: A Functional MRI Case Study
Lanius RA, Hopper JW and Menon RS;
Commented by , 30 Apr 2003
Aim of the study
The authors looked for subjective, psychophysiological and neurobiological differences in a husband and wife who met criteria for acute stress disorder after experiencing the same traumatic event.
Both had been involved in a major motor vehicle accident, they had been trapped in their car, they had witnessed a child burn to death in another vehicle, and feared that they would die too. They had not suffered any physical injuries themselves.
Method
Husband and wife were assessed 4 weeks after the accident and then submitted to traumatic script-driven imagery that caused them to reexperience the initial trauma.
Diagnostic assessment included the Structured Clinical Interview for DSM-IV (SCID) and the Clinician-Administered PTSD Scale for DSM-IV. In addition, husband and wife completed two scales specifically designed for the assessment of dissociative symptoms: the Peritraumatic Dissociative Experiences Scale and the Dissociative Experiences Scale.
Responses to traumatic script-driven imagery were assessed with self-report measures (subjective responses), a heart rate monitor (psychophysiological responses) and functional magnetic resonance imaging (fMRI) (neurobiological responses).
Husband and wife had exposure-based treatment and were assessed again six months later.
Results
Husband and wife met criteria for acute stress reaction and PTSD. The wife had a much higher score on the Peritraumatic Dissociative Scale than the husband (22 versus 1).
The husband reported feeling extremely aroused during the accident. He rescued himself and his wife. The wife reported being “in shock” and “frozen” during the accident.
In response to script-driven imagery the husband reported feeling very anxious and “jumpy”. His heart rate increased 13 BPM from baseline. Increases in BOLD signal intensity were found in anterior frontal, anterior cingulate, superior and medial temporal, left thalamic, and parietal and occipital regions.
In response to script-driven imagery the wife reported feeling “numb” and frozen”. Her heart rate did not change from baseline. Increases in BOLD signal intensity from baseline were found only in occipital regions.
Six month later, the husband no longer had PTSD. His wife still had significant PTSD.
Discussion
The responses exhibited by the husband and wife described in this report were very different in many important aspects. Initial differences included hyperarousal versus numbing and next to none versus severe peritraumatic dissociation.
Traumatic script-driven imagery induced hyperarousal versus numbing, increase of heart rate versus no increase, and widespread versus localized BOLD signal intensity. Outcome after treatment was good versus poor.
On the whole, this report adds important information to a growing body of evidence suggesting that there are probably different types of PTSD. In particular, subjects who react with numbing or dissociative responses are increasingly considered to exhibit a more severe type of PTSD.
The findings, if confirmed, will have major implications for the assessment, treatment and follow-up of patients suffering from PTSD, as well as for our pathophysiological understanding of the disorder.