Diagnosis and Classification

• What is schizophrenia defined as?


  A psychotic disorder marked by severely impaired thinking, emotions, and behaviours
• What types of symptoms do sufferers of schizophrenia experience?


  Both positive and negative symptoms
• What are positive symptoms in schizophrenia?


  Symptoms that enhance the typical experience, such as hallucinations and delusions
• What are negative symptoms in schizophrenia?


  Symptoms that take away from the typical experience, representing a loss, such as speech poverty and avolition
• What is a hallucination in the context of schizophrenia?


  A distorted view or perception of real stimuli or perceptions of stimuli with no basis in reality
• What is the cause of auditory hallucinations in schizophrenia?


  Thought to be caused by an excess of dopamine receptors in Broca’s area
• What are delusions in schizophrenia?


  A set of beliefs with no basis in reality
• What are some types of delusions?


  Persecutory, delusions of grandeur, delusional jealousy, erotomania, and somatic delusional disorders
• What is speech poverty in schizophrenia?


  An abnormally low level of the frequency and quality of speech
• What is derailment in the context of speech poverty?


  A common type of speech poverty caused by dysfunctions in central control
• What does avolition mean in schizophrenia?


  A subjective reduction in interests, desires, and goals, leading to a lack of motivation
• What are the two classification systems for mental disorders?


  The Diagnostic and Statistical Manual (DSM-V) and the International Classification of Disease (ICD-10)
• What is a key difference between the DSM-V and ICD-10 in diagnosing schizophrenia?


  The DSM-V requires at least 2 or more specific symptoms, while the ICD-10 takes a broader approach
• What is the significance of the concordance rates in schizophrenia?


  They suggest a genetic basis for schizophrenia, with higher rates in monozygotic twins
• What are the concordance rates for schizophrenia in monozygotic twins?


  48%
• What are the concordance rates for schizophrenia in dizygotic twins?


  17%
• What are the concordance rates for schizophrenia in siblings?


  9%
• What are the concordance rates for schizophrenia in parents?


  6%
• What do candidate genes suggest about schizophrenia?


  They indicate a genetic basis for the disorder
• What did Ripke et al (2013) find in their genome-wide study?


  They identified 22 loci associated with schizophrenia, including new and previously implicated genes
• What is the implication of high co-morbidity between schizophrenia and other disorders?


  It suggests that schizophrenia may share symptoms with other psychiatric disorders
• What did Buckley et al (2009) find regarding co-morbidity in schizophrenia?


  29% of schizophrenia patients suffered from PTSD, and 50% suffered from depression
• What is a potential issue with the diagnosis of schizophrenia?


  There may be validity issues in differentiating its symptoms from other disorders
• What gender bias exists in the diagnosis of schizophrenia?


  Men are diagnosed more frequently, and women's traits may mask symptoms
• What cultural bias may affect the diagnosis of schizophrenia?


  African Americans may be diagnosed more frequently due to cultural differences in expressing symptoms
• What is the significance of the WHO and the American Psychiatric Association in relation to schizophrenia classification?


  They produce the DSM and ICD, which have different diagnostic criteria
• What is the role of environmental influences in the development of schizophrenia?


  They suggest that factors like the schizophrenogenic mother and dysfunctional thought processing contribute to the disorder
• What is the importance of recognizing different subtypes of schizophrenia?


  It helps in understanding the varying symptoms and treatment approaches
• What are the main differences between the DSM and ICD classification systems for schizophrenia?


  • Produced by different organizations (WHO vs. American Psychiatric Association)
  • Different number of symptoms required for diagnosis
  • Variability in specificity of symptoms
  • Recognition of different subtypes of schizophrenia
• What are the subtypes of schizophrenia recognized in the ICD-10?


  • Positive schizophrenia: prominent delusions, hallucinations, and positive formal thought disorders
  • Mixed schizophrenia: both negative and positive symptoms or neither prominent
• What are the strengths and weaknesses of the current diagnostic criteria for schizophrenia?


  Strengths:

  • Provides a framework for diagnosis
  • Acknowledges the complexity of symptoms

  
  

  Weaknesses:

  • Potential for gender and cultural bias
  • Issues with validity in differentiating from other disorders
• What are the implications of the findings by Gottesman (1991) regarding genetic factors in schizophrenia?


  • Positive correlation between genetic similarity and risk of schizophrenia
  • Suggests a genetic basis for the disorder
  • Highlights the role of environmental influences due to non-100% concordance rates
• What did Ripke et al (2013) contribute to the understanding of schizophrenia?

  • Identified 22 loci associated with schizophrenia
  • Found 8300 separate candidate genes
  • Highlighted the genetic complexity of the disorder
• What are the implications of high co-morbidity rates in schizophrenia?


  • Suggests overlap in symptoms with other psychiatric disorders
  • Indicates the need for careful diagnosis
  • Raises questions about the validity of current diagnostic criteria
• What are the potential biases in the diagnosis of schizophrenia?


  • Gender bias: traits in women may mask symptoms
  • Cultural bias: differences in symptom expression across cultures
  • Validity issues in differentiating from other disorders