Page 12 - JCBP-3-1

Journal of Clinical and
Basic Psychosomatics Somatic symptom disorder etiology

than the event’s manifest danger, it took over 10 years for memory impairment. Newer research indicates that it also
laboratory results to prove her postulation. Perception triggers nervous system effects related to pain perception
9
of trauma as either controllable or uncontrollable affects and dysregulation of the parasympathetic nervous system
the HPA axis response to trauma. This review focuses on (PNS).
the consequences of peritraumatic perception of control/
escapability, as opposed to peritraumatic perception of 6. Cortisol’s central role in trauma
inescapability, or tonic immobility. For extensive coverage outcomes
of the etiology of PTSD and perceived inescapability/ 6.1. Memory
tonic immobility (Bovin et al., Hagenaars and Putman,
Lima et al., Marx et al., Olff et al., Rocha-Rego et al., and Perception of control is a determining factor in whether
Volchan et al. 3,34-39 ). amnesia develops, or indelible memory of trauma
develops, in both animal and human studies. In a seminal
5. Defense cascade: Fight, flight, or freeze? work by Drugan on rats exposed to trauma/stress, simply
The defense cascade refers to a common series of by varying ‘controllability’, he and his colleagues succeeded
physiological and behavioral events triggered by danger in inducing either long-term traumatic amnesia, or
or perceived threat in animals and humans. Animals contrarily, tonic immobility and depression/PTSD. He
move through the cascade in a predictable fashion, from defined controllable stress as “the subject is allowed to
attentive stillness (hyperalert assessment) to fight, to flight, make an active behavioral response to alter the pattern,
46,p.246
to freeze, depending on their species (e.g., some animals onset, duration, or intensity of stress”. In the escapable
are suited to fight more than flight). 38,39 Freeze, or in its stress paradigm, the rats had subsequent amnesia for the
extreme form, tonic immobility, is characterized by gross experience. Postmortem, Drugan found elevated levels
motor inhibition, a fixed stare, suppressed vocalization, of corticosterone (rat cortisol) binding with nicotinic
lower body temperature, and even temporary paralysis. acetylcholine receptors (nAChRs) in the hippocampus,
It is a last resort for the animal; “playing dead” is an and elevated gamma-aminobutyric acid (GABA) in the
attempt at self-preservation when no other escape seems amnestic rats. He concluded that a hypercorticosterone
possible. In humans, as early as 1989, van der Kolk, condition was created by the escapable stress paradigm,
9
Greenberg, Orr and Pitman hypothesized that the freeze and either cortisol or GABA was responsible for the rats’
46
response led to PTSD symptoms. Others followed, traumatic amnesia.
40
documenting similarities between tonic immobility Perceiving trauma as controllable or escapable tends to
and symptoms observed in patients with dissociation, have a protective amnestic effect on the mental health of
including some who were diagnosed with PTSD. The people and animals, and may, in some cases, be useful for
41
peritraumatic dissociative experiences questionnaire was survival and species success. Moderate to high amounts
developed, with derealization and dissociation predicting of cortisol are also useful to an organism preparing for
PTSD symptoms. 42,43 Derealization is concerned with the fight or flight because cortisol helps mobilize energy
perception of trauma, and dissociation is connected to a resources, increases cardiac activity, primes muscles for
freeze response. action, and potentiates the startle response. 10,47-49 However,
In humans, as dissociation increases, cortisol secretion because nearly every neurotransmitter system is affected
decreases. Forebrain areas engage if critical processing of by exposure to prolonged stress, escapable or otherwise,
44
the threatening situation occurs, which is a slower brain negative consequences are high as well.
activity, whereas midbrain areas engage if immediate Compelling prospective evidence in human’s shows, like
panic or tonic immobility occurs, which is a faster cortical rats, our freeze/inescapable stress response leads to PTSD,
reaction. 10,45 The assessment of how serious or imminent whereas our fight/flight/escapable stress response leads to
a danger or encroaching threat is, causes one cortical either amnesia or no PTSD For example, many people
50
area to fire faster than another, determining the amount who qualify for acute stress disorder in the early days
and type of neurochemicals that circulate. In the case of following a trauma no longer meet symptom criteria after
an inescapable threat, initial attentive stillness is followed 30 days. They have resolved the trauma in some manner,
immediately by tonic immobility, whereas when a threat is and this is linked to moderate cortisol levels. Research on
perceived as potentially escapable, an attempt to bargain, car accident victims is demonstrative. Delahanty found

fight, or flee occurs. The key neuroendocrinological among 134 motor vehicle accident victims and 43 minor
9,10
player relevant to both these reactions is cortisol. For injury controls, the group who felt responsible for their
decades, we have known that cortisol secretion has dose- vehicle crashes (peritraumatic perception of control)
dependent, clinically relevant, differential effects on had significantly fewer or no PTSD symptoms, three and

Volume 3 Issue 1 (2025) 6 doi: 10.36922/jcbp.4254