phobias Flashcards
unconditioned stimulus
biologically significant event
unconditioned response
the response evoked by the unconditioned stimulus
conditioned stimulus
previously neutral stimulus that acquires a response by being paired with an unconditioned stimulus
conditioned response
the response evoked by the conditioned stimulus
what is a phobia
- “irrational” fear of an “objectively harmless” stim
- low reality of danger
- high fear which is the emotional response to real or perceive imminent threat
- anxiety is anticipation of future threat
what causes a phobia
- associative learning (conditioning) account
- acquired through experience of phobic stimulus (CS) being paired with a really frightening or painful event (traumatic US)
- 2nd order/higher-order conditioning: CS–>aversive US
how are phobias treated
- exposure therapy
- e.g. systematic desensitisation: teach relaxation techniques –> establish hierarchy of fear
- can extinguish the association by giving the experience without pain
- fear & relaxation mutually incompatible
- treatment is theoretically informed - ideas of CC
Rachman (1990) why need to revise conditioning model
- phobics can’t always recall when a phobic stimulus was paired with traumatic event
- people who experience stimulus–>trauma don’t always go on to develop a phobia of that stimulus
- incidence of phobias != likelihood of experiencing stimulus–>trauma e.g. ppl can have phobias of things never experienced
3 pathways to fear
rachman (1990)
- conditioning
- vicarious (observing another person expressing fear of a stimulus
- information/instruction (stories/warnings)
revaluation
addressing problems of phobias - rachman
- associative learning will give rise to a fear CR, to the extent that the US is evaluated as aversive
- this evaluation may change after the initial associative experience
- Davey et al. (1993)
- Rescorla (1974). Revaluation of conditioned fear in rats
davey et al. (1993)
revaluation
- patient HB applied for therapy for spider therapy
- wasn’t scared originally but was after others fear from spider
- experience later inflated by parents
- unpleasant thing didn’t happen
rescorla (1974)
revaluation
- rats can have associative experience between neutral & aversive which can later be changed
- small shock with tone
- then split into 4 groups - revaluation groups
- what happens when change mem of shock whilst not being paired with tone
- lower suppression ratio = more fear
- changing shocks to be higher during revaluation increases fear of tone: aversiveness inflated
S-R associations
problems with phobias - rachman
- phobic stim may not be associated with a painful/aversive US (S-S learning), but with the fear response the aversive event (S-R learning)
- some phobic learning may result from “false alarm” experiences - including panic attacks rather than true harm/danger
- helps us go beyond “memory loss” as an argument against Rachman’s 1st problem
contemporary learning theory being able to address some of Rachman’s problems
- prevention of associative learning (Davey, 1992)
- despite CS-US pairings, associative learning may not take place (despite learning there is no learning) - latent inhibition and overshadowing
latent inhibition
conditioning more often when it is novel. Tone lots of times were it becomes familiar, if you then present a shock conditioning happens very slow than if the tone was novel
- difficulty learning a stim if it was previously neutral
overshadowing
CS interested in paired with US but when present CS at same time that is more salient, attention shifts to other thing, if tone & bright light: bright light will overshadow the tone previously paired
- a weaker stimulus will not be learned if a stronger one is present
selective associations
overcoming problems with phobias - rachman
- some CS-US associations are predisposed to be learned, others are not
- biases present in ppl, monkeys and rats
- cook & Mineka (1990) - monkeys readily associate sight of snake, but not flowers, with fear in another monkey
- garcia & koelling (1966) - flavour-illness association can happen with one trial but not the case for hard to learn associations
associative experiences
- all foregoing accounts imply some form of associative experience is important for acquisition of phobia
- Menzies & Clarke (1995) suggest experience is not necessary for phobia: selective associations taken as evidence for this, some fears come into world without learning but can also learn to not be scared of them
- Merckelbach et al. (11996) disagree: ev for learning origin is convincing
- So we need research on what experiences ppl with phobias have had
retrospective studies
phobias
done with ppl who already have phobia but best if research could be prospective (what happened before the phobia)
ost (1991) review of retrospective studies in clinical phobic patients
- blood/injection phobia
- used POQ (phobic origins questionnaire)
- 9 questions: 2 conditioning, 4 vicarious, 3 instruction
- focused on how ppl believe phobia started - responses classified as conditioning, vicarious or instruction
- common to least common: conditioning –> vicarious –> no recall –> instruction/information
McNally & Steketee (1985)
- 22 ppl who had applied for beh treatment for animal phobias
- structured interview focussing on experiences round start of phobia
- 68% could provide no info on onset of phobia
- out of 7 that could recall - 5 reported conditioning-like experiences
- most common thing ppl would report that they feared was that they feared was the anxiety/panic if they encountered rather than aversive event from the animal
- results linked to concept of “anxiety sensitivity”
himle et al. (1991)
phobias
- reviewed case records of simple phobics
- onset events in 5 types
1. realistic
2. spontaneous
3. vicarious/observational learning
4. gradual onset
5. lifelong fear - what causes the phobia depends on phobia itself
doogan & thomas (1992)
- none of previous studies showed experience is critical for phobia acquaition - no non-phobic controls
- students & children classified as high or low on fear of dogs
- no difference between either when bitten by dog or chased at least once in regards to high and low fearing - experience doesn’t show whether you are going to become high or low fearing
- significant difference between high and low when being frightened
- significant difference between high and low when looking at no contact prior to first frightening experience
The first two rows of data in atable show that, irrespective of age, high dog-fearers and low dog-fearers did not differ in the number of times they had been bitten or chased by a dog at least once. However, they did differ in terms of the number times they had been frightened by a dog. Using these data, and your knowledge of learning, how do you think the authors explained this pattern of results?
The fear was acquired or maintained by Stimulus-Response learning
Doogan and Thomas (1992) found that that almost all (20/21) of the high dog-fearing adults had little or no direct contact with dogs prior to their first frightening encounter with them. However, only 15/49 of the low dog-fearing adults had little or no direct contact with dogs prior top their first frightening encounter with them. Using these data, and your knowledge of learning, how do you think the authors explained this pattern of results?
Latent inhibition
In a(n) _ study of phobia acquisition, the investigators design the study and recruit participants after the phobia has been acquired. In a(n) _ study the investigators design the study and recruit participants before the phobia has been acquired.
Retrospective/Prospective
A case has been reported of M.F. who at the time was a 29-year-old male who worked as a bank employee.
“On one occasion the bank was robbed, and during the robbery M.F. was threatened with a gun. He had not been particularly anxious at the time and returned to work the next day without complaining of any residual fear symptoms. However, 10 days after the robbery he was interviewed by the police, and during this interview he was told that he was very lucky to be alive because the bank robber was considered to be a dangerous man who had already killed several people. From this point on M.F. did not return to work and developed severe PTSD symptoms.” This case was interpreted by the authors of the report as:
US revaluation
