Post-Traumatic Stress Disorder Flashcards
Facts
- became specific category in 1980
- different to other anxiety based disorders as specific events must be cause of symptoms
- often occurs after experience of distressing event
- symptoms different to other anxiety disorders: increased arousal, avoidance/numbing of emotions, flashbacks
Symptoms of PTSD
hypervigilance
flashbacks
startle responses
intrusive thoughts
^ these have sub-groups but these are main categories
^ all are potentially life threatening in their severity
DSM-V Criteria
criteria are specific but relatively inclusive
more specific now that experience of severe stress can cause PTSD
- trauma exposure and re-experiencing of event
- intrusive symptoms (at least 1)
- avoidance symptoms (at least 1)
- negative alterations in cognition and mood (at least 2)
- alteration in arousal or activity (at least 2)
- duration at least one month
- significant impairment
Controversy
McNally, 2003
- people can now fake PTSD more easily
- accumulating evidence for those claiming to have recovered memories of trauma being prone to exhibit false memory effects
- PTSD now equated with merely experiencing stress - broadened diagnostic criteria allows lots of people in
- falls now to distinguish between normal stress and a psychological disorder
Fact about prevalence
in last 10 years more US soldiers have committed suicide than have been killed in Afghanistan
in 2007 > 20,000 troops on anti-depressants/ prescription sleep meds
gender and ethnic differences in prevalenc
Rothbaum et al., 1992 - PTSD after rape - 92% still had one week later but only 47% three months later - spontaneous recovery
Issue about disorder
for any theory of PTSD, not everyone who has trauma experiences develops PTSD
different levels of susceptibility
either psychological or biological vulnerabilities factors or psychological strategies developed to cope must explain this
PTSD has many different symptoms but most theories only address some - Brewin and Holmes, 2003
Vulnerability factors
number of factors characterise those likely to develop PTSD after trauma
- tendency to take personal responsibility for traumatic event
- developmental factors i.e. early separation from parents
- family history of PTSD
- existing high levels of anxiety
5 main theories
Theory of shattered assumptions Conditioning theory Emotional processing theory Mental defeat Dual representation theory
Theory of shattered assumptions
Janoff-Bulman, 1992
people develop schemas that suggest the world to be a safe place and that people are good
when traumatic events occur they severely challenge this belief
individual left in state of disbelief, shock and conflict
challenges core beliefs and left in state of unreality
person updates views of world for more negative perspective
plausible but facts do not support
Challenge to theory of shattered assumptions
Resick, 2001
those who have already experienced previous trauma are more likely to develop PTSD
It is NOT those who have a core belief that the world is a safe place
Conditioning theory
symptoms due to classical conditioning
UCS becomes associated at time of trauma with situational cues associated with place and time (CS)
if similar or same cues are met then elicited are same arousal and fear
development of cog and physical avoidance responses mean CRs are not extinguished
doesn’t provide full explanation - why do not all develop?
Mowrer’s Two-Factor Learning Theory
avoidance behaviours can be both passive and active
passive avoidance - avoid trauma related thoughts and behaviours
active avoidance - thought suppression, escape behaviours
avoidance prevents extinction
Emotional processing theory
Foa, Steketee and Rothbaum, 1989
intense nature of PTSD creates a trauma representation in memory - becomes strongly associated with other contextual details of event
avoidance behaviours means little opportunity for networks to weaken
trauma so significant that representations are so different to everyday experience representations
Mental defeat
a cognitive model (also comprehensive)
Ehlers and Clark, 2000
a specific psychological factor increases vulnerability - specific frame of mind called ‘mental defeat’
- individual sees self as victim
- info about event all processed negatively
- negative state leads to more distress and causes maladaptive behaviours
- 3 maintenance mechanisms prolong distress in PTSD (circular model) (nature of memory, negative appraisals, maladaptive behaviours)
- Nature of traumatic memory
explains the occurrence of re-experiencing symptoms
- problems in recalling trauma - not coded properly - so many gaps in memory
- forms of intrusive memories
a disturbance of autobiographical memory characterised by poor elaboration and contextualisation, strong associative memory and strong perceptual priming
Support for re-experiencing of flashbacks
McFarlane, 1992
longitudinal study, 290 firefights exposed to natural disaster - symptoms assessed at 2, 11 and 29 months post-trauma - avoidance symptoms appeared to be a by-product of intrusions
Michael et al., 2005
assault survivors studied after trauma and 6 months later - 66% reported intrusions - suggests maladaptive behaviours
Support for problems in recall
Halligan et al., 2003
73 victims of assault
assessed for post-assault and 6-months later for symptoms, assault memory narrative and memory
disorganisation in those with PTSD - it is both memory and disorder specific
why do trauma memories have unusual qualities in PTSD?
poor integration into autobiographical memory base (lack of context, problems in intentional retrieval, easy triggering by matching cues)
conditioning: enhanced SS and SR associations
Implicit memory
influences on trauma memories
breakdown in cognitive processing
physiological arousal
- Negative appraisals
they are highly idiosyncratic - may confirm existing negative beliefs
can link to shattered assumptions theory
support for negative appraisals
Foa et al., 1999 162 adults without trauma 185 with trauma, no PTSD 170 with PTSD those with PTSD had higher levels of negative view of self, world and self-blame Dunmore et al., 2001 57 victims of assault completed PTSD symptom questionnaire and measures of negative appraisal symptoms assessed 6-months later PT appraisal predicts 6-month symptoms
- Maladaptive behaviours
coping strategies - to control threat but maintains PTSD
- direct production of symptoms (suppression, selective attention)
- prevention of change in negative appraisals (safety behaivours, avoidance, rumination)
- prevention of change in nature of trauma memory (avoidance of thinking about trauma, suppressing emotions)
Support for maladaptive behaviours
Harvey and Bryant, 1998 - thought suppression
48 accident survivors - 1/2 with stress disorder
monitored thought for 3x5 mins and pressed button if trauma thought
suppression associated with rebound effect stronger for those with stress disorder
Michael et al., 2007 - rumination
thoughts of those with PTSD include what if and why questions - amount and quality of rumination important predictor of symptoms
Dual representation theory
PTSD - hybrid disorder - involves 2 separate memory systems
1 - verbally accessible memory - registers memory of trauma
2 - situationally accessible memory - records info about event that may have been too brief to apprehend consciously
