OCD- Psychopathology Revision

OCD- Psychopathology Revision

1. Characteristics

   • Behavioural
     • Compulsions
       • Repetitive behaviours which reduce anxiety
       • Response to obsessions
     • Avoidance
       • Avoiding situations that may trigger anxiety
   • Emotional
     • Anxiety/distress
       • Obsessions are unpleasant and frightening
       • The urge to repeat a behaviour creates anxiety
     • Co-morbid with depression
       • Low mood
     • Disgust
       • For self or for other things
   • Cognitive
     • Obsessions
       • Recurrent unpleasant thoughts
       • Awareness
         • Sufferers know their thoughts are irrational

2. Explanations

   • Genes
     • 230 Candidate genes
       • Polygenic
       • Create vulnerability to OCD
     • Aetiologically heterogenous
       • Different genes cause OCD in different people
     • Evaluation
       • Supporting evidence
         • Twin studies
           • 68% concordance in MZ
           • 31% concordance in DZ
       • Too many candidate genes
         • Little predictive value
         • Difficult to treat
       • Ignores role of environment
         • MZ twins often have very similar environments compared to DZ
         • Not solely genetic
   • Neural
     • Serotonin
       • Low levels
         • Lower mood
     • Abnormal functioning of frontal lobes
       • Impaired decision making
     • Abnormal functioning of parahippocampal gyrus
       • Deal with negative emotions
     • Evaluation
       • Supporting evidence
         • Antidepressants which increase serotonin levels help treat OCD
           • Suggests serotonin does play role in onset/maintenance of OCD
       • The neural abnormalities may be the result of OCD, not the cause
       • Serotonin-OCD link may be due to co-morbidity with depression

3. Treatment

   • Drug therapy
     • SSRIs
       • Prevents serotonin re-uptake
         • Serotonin continues to stimulate post-synaptic neuron
       • Increases levels of serotonin
       • Takes 3 months for it to take effect
       • Often combined with CBT
     • Alternatives
       • Tricyclics
         • Same effect on serotonin system
         • More severe side effects
       • SNRIs
         • Also increase levels of noradrenaline
     • Evaluation
       • It is effective
         • Reduces severity of symptoms
         • Improves quality of life
         • Works for 70% of patients
       • Cheap and non-disruptive
       • Negative side effects
         • Tremors
         • Weight gain
         • People stop taking the drugs
       • Drug companies over-reemphasis effectiveness
       • Doesn't account for reactive OCD