Schizophrenia

• Positive symptoms of schizophrenia


  • Delusions - bizarre beliefs that seem real to the schizophrenic
  • Hallucinations - unreal perceptions of the environment that are auditory, visual, olfactory or tactile
  • Disorganised Speech - 'word salad' where speech is incomprehensible or 'derailment' where an individual slips between topics
  • Disorganised/Catatonic Behaviour - inability or lack of motivation to initiate or complete tasks
• Negative symptoms of schizophrenia


  • Speech Poverty (Alogia) - lessening of speech fluency and productivity
  • Avolition - reduction of interests and desires, as well as an inability to initiate and persist in goal-directed behaviour
  • Affective Flattening - reduction in the range and intensity of emotional expression, including facial expression
  • Anhedonia - inability to experience pleasure
• Reliability


  Consistency of a measure, as in the same data should be produced by a measurement if it is taken on successive occasions
• Validity


  Accuracy of a measurement - whether or not an observed effect is genuine
• Neural correlates


  Changes in neuronal events and mechanisms that result in the characteristic symptoms of a disorder, which in the case of schizophrenia may be damaged connections between the hippocampus and the prefrontal cortex
• Dopamine hypothesis


  When the neurotransmitter dopamine is in excess in regions of the brain, positive symptoms of schizophrenia can be observed
• Double bind theory


  Receiving contradictory information from a family member, such as being told they love them whilst sneering at them
• Expressed emotions


  A family style in which there may be overinvolvement in a child's life, and a poor style of communication
• High EE environment


  Receiving contradictory information (being told 'I love you' by a sneering person') renders an individual unable to respond to future information, causing cognitive symptoms of schizophrenia
• Cognitive approach to hallucinations


  Hallucinating individuals experience hypervigilance due to an excessive focus on auditory stimuli, such individuals find it hard to distinguish between imagery and sensory based perception. This is not corrected as schizophrenics do not reality test as non-schizophrenics do.
• Cognitive approach to delusions


  During the formation of delusions, patients have their interpretations of their experiences controlled by inadequate processing of information
• Atypical antipsychotics


  Carry a lower risk of extrapyramidal side effects and are believed to, unlike typical antipsychotics, have an impact of reducing negative symptoms as well as positive ones. These are also suitable for treatment resistant patients.
• Why atypical antipsychotics have fewer side effects

  Atypical antipsychotics do not only block D2 receptors, but have a stronger affinity for serotonin receptors, and a lower affinity for D2 receptors, which is believed to reduce the risk of side effects.
• How antipsychotics work


  Antipsychotics are dopamine antagonists which are substances that decrease the activity of dopamine, by blocking receptors so that dopamine cannot stimulate them.
• Why drug therapies are preferred

  They are effective, cheap, and require less effort on the part of the patients, increasing the chances of them persisting in the treatment.
• Token Economy


  A form of therapy in which desirable behaviours are encouraged by the use of reinforcements. Rewards are given in exchange for tokens earned when desirable behaviours are performed.
• Token Economy is considered unethical because psychiatrists have to be in control over food and other things that act as primary reinforcers, and patients have to exchange tokens given to them by the psychiatrists to have access to these things, which contradicts the notion that all humans have the right to things like privacy and food without having to earn them.
• Interactionist Approach to Schizophrenia


  A compromise explanation that suggests schizophrenia develops in individuals who have a genetic vulnerability (diathesis), following an activating event (stress).
• Symptom overlap


  Some symptoms may not be unique to one disorder, but rather shared amongst many disorders. An example of this is social anhedonia, which is common between both schizophrenia and depression.
• Comorbidity


  The extent to which two or more conditions occur simultaneously in a patient, like schizophrenia and depression.