Explanations of phobic disorders

Explanations of phobic disorders

1. Biological explanations

   • Biochemical
     • GABA - neurotransmitter released in response to high levels of arousal
       • Inhibits Anxiety
         • Low levels means excited neurons are not restrained
       • Cowley et al - BZs (GABA substitute) used to decrease anxiety & arousal. Effects only short term
     • Amygdala & Hippocampus - activated in response to stress
       • Part of the ancient brain activated in emotional situations
       • Tilfors et al - PET scans show phobics have increased blood flow to the Amygdala
       • Furmark et al - Citalopram used to decrease Amygdala blood flow, successful treatement
       • Not all phobics show increased blood flow
       • High levels of noradrenaline (produce stress reponse) can damage Amygdala & Hippocampus
   • Genetic
     • Family studies
       • Fyer et al - probands (first to seek diagnosis for genetic disorder) have x3 many relatives with phobias compared to control
         • Ost - 64% blood phobics had at least one relative with the same phobia
       • Solyom et al - 45% phobics had at least one relative with a phobia compared to 17% in control
       • Fyer et al - 31% first degree relatives diagnosed with phobia - only 2 were the same
         • Genetic explanation cannot explain discrimination between phobic stimuli
       • Not all phobias have the same genetic inheritability
         • Kendler et al - 67% agoraphobia, 59% blood/injury, 51% social phobia, 47% animal phobia
           • Torgerson - only 31% agoraphobia concordance in MZ twins. No concordance in DZ twins
       • Brown et al - phobias more common in African-American than White populations. Cultural factors are important
       • Diathesis stress model, individuals predisposed genetically, switched on by environment
     • Twin studies
       • Torgersen - MZ x5 more likely to have anxiety phobia with panic attack than DZ
         • MZ twins more likely to share similar experiences than DZ twins, more interests even when brought up apart. Interests have a genetic tendency
     • Inherited tendencies
       • High arousal in the ANS causes high levels of adrenaline - oversensitive fear response
         • Beta blockers a successful treatment reducing anxiety
       • Dopamine pathways make you more readily conditioned, easier to develop phobias
         • Tiihonen et al - lower number of dopamine receptors in social phobics
           • Differences don't necessarily cause phobias, may be symptoms caused by phobias
       • Abnormal Serotonin levels
     • Phobia develops if an individual is genetically predisposed
   • Evolutionary
     • Biological preparedness - phobias provided our ancestors with an adaptive advantage, more likely to survive & pass on phobic gene
       • Cook & MIneka - easier to condition monkeys to fear toy snakes than teddies or toy rabbits
       • Ohman - easier to condition humans to fear snakes than flowers
       • Phobias linked to ancient fears fears, modern things not round long enough to provoke phobic response i.e guns & electricity
       • Rapidly learn association between life threatening stimuli & fear - difficult to extinguish
         • Mineka et al - monkeys develop snake phobia if they see another monkey showing fear. Same effect not seen for flowers
     • Prepotency - tendency to response after a direct experience i.e anxiously to snake like movement
       • Anxiety after an event not an evolutionary advantage therefore response developed to potential threats
       • Ohman & Soares - snake phobics had greater fear response to masked pictures of snakes than non phobics - evidence for prepotent signals
     • Merckelbach - most clinical phobias non-prepared not prepared
     • Davey - phobias develop from expectancy bias of future negative consequences, not an evolutionary link. Explains modern phobias

2. Psychological explanations

   • Psychodynamic
     • Phobias are a conscious expression of repressed conflicts
       • Dealt with by the ego repressing undesirable memories into the unconscious
         • Repressed memories can be projected onto neutral situations, not the real fear
     • Freud - little Hans developed a horse phobia as he was scared his mother would leave him. Projected this onto phobia
       • Unique individual, case studies cannot be generalised
       • Lacked objectivity, His father & Freud interpreted evidence based on their beliefs on the origin of phobias
       • Can be explained by classical conditioning
     • Bowlby - agoraphobes often had early family conflicts. Leads to separation anxiety. Suppressed & reappear as agoraphobia
     • Whiting et al - phobias more common in cultures with structured child rearing. Stricter parenting may lead to repressed desires
   • Behavioural
     • Classical conditioning
       • Little Albert developed a phobia to white furry objects
         • Conditioned to fear white rat
           • Stimulus generalisation
             • Feared father christmas & rabbits
       • Sue et al - phobics often can recall a specific incident causing the phobia, i.e being bitten by a dog
         • Ost - not all phobics can remember a first experience, memory may have been repressed
       • Bergman - failed to condition infants to fear wooden blocks, may only be ancient phobias such as animals - biological preparedness
     • Operant conditioning
       • Two process theory - phobias acquired through classical conditioning & maintained by operant conditioning
       • Avoidance of stimulus reduces fear & provides negative reinforcement
     • Social learning
       • Phobias can develop observing others having a phobic response
         • Behaviour is imitated
         • Child develops phobia observing parents and copies as behaviour seems rewarding
       • Bandura & Rosenthal - participants saw a confederate receiving 'shocks' when a buzzer sounded. Emotional reaction to the sound developed
       • Different phobias have different roots, agoraphobia from a specific incident, arachnophobia from modelling
       • Culturally most people are scared of snakes yet few have seen them
     • Can account for cultural differences, culture specific role models can influence phobia development
   • Cognitive
     • Phobias develop due to irrational thinking
       • Can come from a traumatic experience
       • Exposure doesn't initiate phobia, irrational thoughts do
     • Beck et al - irrational thoughts create anxiety, fear of being in a high anxiety situation creates a phobia. Phobics often overestimate fears
     • Phobics more likely to overestimate risks, predisposed to develop phobias because of cognitive style
     • beck et al - phobics felt anxiety close to a stimuli but not far away, anxiety increase the closer they got
       • Phobics more scared of the fear of fear, not the object itself