Stress & PTSD Flashcards
Stress
A real or interpreted threat to the physiological or psychological integrity of an individual
Results in physiological and/or behavioural responses
We all perceive stress differently
Hooke’s law
Wear & tear of everyday life
How long until the spring snaps
Cannon(1932): homeostasis, fight or flight
Homeostasis; biological self-regulation, enables an organism to adapt to life’s demands, we’re built to prepare to fight or flight
Stressor; stimulus resulting in imbalance threatening homeostasis
Stress response; response of an organism to maintain or re-establish homeostasis
General adaptation syndrome; Selye (1956)
3 stage model of chronic stress
1) alarm; immediate response
2) resistance; bodies ability to cope with higher level of stress
3) exhaustion; need a break from stress or exhaustion occurs, rush if developing other conditions, reduced immune system
Cognitive effects of stress
Loss of concentration
Memory loss
Reduced decision-making ability
Behavioural effects of stress
Over eating Under eating Reduced work performance Reduced time management Arguments
Physiological effects of stress
Increased heart rate
Increased blood pressure
Increased galvanic skin response
Emotional effects of stress
Anxiety
Anger
Low motivation
Increased jealously/insecurity
Sympathetic-adrenal-medulla (SAM) axis
Sympathetic nervous system
Immediate stress response/fight or flight
Norepinephrine (in brain)
Epinephrine (in blood)
Generates more energy, conserving every, more blood & oxygen to brain, heart & muscles, decreased blood loss after injury
Hypothalamic-pituitary-adrenal (HPA) axis
Hormone mediated
Slower response
1) stress
2) corticotropin releasing hormone
3) adrenocorticotropin hormone
4) cortisol
Negative feedback loop
Short term release of cortisol is protective
Adaptive long term release can lead to immunosuppression, CVD & hypertension
Early life stress can lead to high cortisol releasing hormone & altered cortisol
Measuring acute stress
High salivary amylase
High norepinephrine in blood
Measuring chronic stress
Diurnal (daily) curve of cortisol response
Cortisol awakening response; natural rise in morning, prepares people for day
Altered in mental health disorders
Life events as stressors
Stress exposure significantly associated with depression
Increased cortisol awakening response in men who have experienced early life stress compared to men who have not
Still an effect even if no MH disorder
If experienced trauma; higher CAR
low parental care; increased CAR
CAR higher in patients with psychosis
Ways to measure life events as stressors
Social readjustment rating scale; Holmes & Rae (1967)
College life inventory (Renner & Macklin, 1998); gives value to different events
Childhood trauma/adversity
Frequent in people with psychosis
Increase in the likelihood of developing psychotic symptoms in adulthood if having experienced childhood adversity
Childhood adversity associated with the severity of symptoms & cause of schizophrenia
Has an effect on cognition (memory, executive functioning, cognitive performance)
Importance of appraisal
Lazarus; influential stress theorist & researcher
Perceived stressors
Transactional model
Appraisal; 15 core relational themes
Some stressors can be positive if we believe we can cope
Risk factors
neuroticism
external locus of control
type A personality (exaggerated sense of time urgency, competitive, hostility & drive, linked to 2x increased risk of CHD, type D personality?
Protective factors
Conscientious Extra version C+E= resilience Openness to experience Agreeableness Dispositional optimism Internal locus of control
Influence of stress on mental health
Yerkes-Dodson law; optimal stress=high performance
Higher sense of control, more likely to experience stress as excitement rather than depression or anxiety
Salutogenic model
Anyonvosky, medical sociologist
Health is on a continuum defined by how a person manages stress
Generalised resistance resources, conprehensibility, manageability , meaningfulness & sense of coherence (confidence that environment is predictable & that things will work out)
Erickson & Lindstrom (2005)
Reviewed 458 publications of salutogenic model
Found that sense of coherence promoted resilience & positive health
Van der Hal-van Raalte et al (2008)
203 holocaust survivors
Strong sense of coherence protects from PTSD even in old age compared to survivors with weak SOC
Trauma & stress-related disorders
Separate in DSM-5 from anxiety disorders
Major diagnostic category is PTSD
primary precipitating cause is traumatic experience
Can be diagnosed even if you have just witnessed an event
PTSD
Intrusive symptoms e.g. disturbing dreams
Avoidance responding
Negative changes in cognition & mood
Increased arousal & reactivity
Symptoms began at event or after & lasted for at least 1 month
Acute stress disorder
Similar to PTSD
much shorter duration
Begins within 3 days-1 month after event
Lasts for 3 days-1 month
Prescribe of PTSD? Actually a disorder?
Effects of military service on mental health; Hoge et al (2004)
2530 studied before Iraq deployment 1709 studied after return PTSD before; 9.4% PTSD after; 18% Demographics of pp were similar to those of the general, deployed non-officer pop in Iraq
PTSD triggers
Rape; 90% chance Torture; 70-90% chance Prisoners of war; <50% Flood & earthquake survivors; 20-25% Motor vehicle accident victims; 15% Overall US prevelance rate; 1%
Conditioning theory
symptoms associated with PTSD due to classical conditioning
Trauma (UCS) associated with other cues (CS)
Conditioned fear response does not extinguish due to avoidance responses
Conditioning theory doesn’t explain;
Individual nature of responses to trauma
Range if symptoms specific to PTSD e.g. dissociative experiences & flashbacks
Why only some people?
Pre-existing personality factors
Possible genetic disposition
Key appears to be the fear reaction to the experience
Biological factors
30% heritability
Genetically wired heightened startle response & endocrine system response
Reduced hippocampul volume
Vebtrimedial frontal cortex; amygdala circuitry
Other factors
Tendency to take responsibility for the traumatic event & the misfortunes of others involved in the event
Developmental factors
Family history of PTSD
Existing high levels of anxiety or pre-existing psychological disorder
Low IQ, link to coping strategies?
Types of experiences reported at time of event
Mental defeat
Individual vulnerability in increased in those who see themselves as a victim
Loss of individual autonomy
All info about trauma is processed negatively & person views themselves as unacceptable to act effectively
Perceived lack of control prevents processing of the memory
Avoidance & dissociation
Avoidance coping more likely to lead to PTSD
Dissisociation as an avoidant strategy; dissociation used to allow person to detach & distance themselves from the trauma
Individuals who show dissociative symptoms at the time of trauma more likely to develop PTSD
Emotional processing theory
Information processing model
1) Representation of memory becomes strongly associated with other contextual details due to intense nature of trauma
2) leads to formation of representations & associations in memory different to those formed from everyday experience
3) previous assumptions about how safe the world is leads to a sensitisation in terms of the threshold to display fear response
People with fixed ideas of self & world prior to trauma more susceptible to PTSD
Dual representation theory; Brewin (1996)
Trauma memories are represented in a more fundamentally distinct way
Re-experiencing arises when trauma memories become dissociated from the ordinary memory system
Recovery involves transforming them into ordinary or narrative memories
Memory model
Verbally accessible memories (VAM) vs situationally accessible memories (SAM)
Verbally accessible memories
Memories consciously processed at time of trauma
Contain info before, during & after traumatic event; temporal context is encoded
Can be deliberately retrieved
Integrates with personal context comprising past, present & future
Hippocampus involvement
Situationally accessible memories
Perceptual processing (sights, sounds, touch)
Stores info about bodily response
Memories difficult to communicate to others
Responsible for flashbacks
Amygdala involvement
Triggered involuntarily by situational reminders
