Schizophrenia

• Schizophrenia is defined as "a psychotic disorder marked by severely impaired thinking, emotions, and behaviors"
• Schizophrenic patients are typically unable to filter sensory stimuli and may have enhanced perceptions of sounds, colors, and other features of their environment
• Sufferers of schizophrenia may experience positive symptoms (enhance typical experiences) and negative symptoms (take away from typical experiences)
• Positive symptoms of schizophrenia include hallucinations and delusions
• Negative symptoms of schizophrenia include speech poverty and avolition
• Hallucinations in schizophrenia are characterized by a distorted view/perception of real stimuli or perceptions of stimuli with no basis in reality
• Delusions in schizophrenia are beliefs with no basis in reality, such as persecutory delusions or delusions of grandeur
• Speech poverty in schizophrenia occurs when there is an abnormally low level of the frequency and quality of speech
• Avolition in schizophrenia is a subjective reduction in interests, desires, and goals, leading to a behavioral reduction of self-initiated and purposeful acts
• There are two classification systems for mental disorders: The Diagnostic and Statistical Manual (DSM-V) and the International Classification of Disease (ICD-10)
• The DSM-V and ICD-10 have different requirements for the diagnosis of schizophrenia
• Different subtypes of schizophrenia include positive schizophrenia and mixed schizophrenia
• There is a significant comorbidity between schizophrenia and other mental health disorders like OCD and post-traumatic stress disorder
• Gender bias and cultural differences can impact the diagnosis of schizophrenia
• Schizophrenia has a genetic basis, with evidence showing a positive correlation between genetic similarity and the risk of developing the disorder
• Candidate genes have been identified for schizophrenia, indicating a polygenic disorder with multiple contributing genes
• The dopamine hypothesis suggests abnormal dopamine levels in different brain areas contribute to schizophrenia
• Positive symptoms of auditory hallucinations in schizophrenia are due to overactivity of neurotransmission in the auditory areas of the brain
• Negative symptoms of schizophrenia, such as speech poverty and avolition, may be linked to hypodopaminergia in the prefrontal cortex
• The dopamine hypothesis has implications for the development of drug treatments for schizophrenia, such as antipsychotics/dopamine antagonists
• Neural correlates refer to specific patterns of cortical activity or neural structures that coincide with specific psychological symptoms in schizophrenia
• Abnormally low levels of activation in the ventral striatum may be associated with the negative symptom of avolition in schizophrenia
• Functional abnormalities in the anterior cingulate and left temporal cortex are associated with the misidentification of self-generated speech in patients with auditory verbal hallucinations in schizophrenia
• Evidence supports the biological and genetic basis of schizophrenia, with mutations in DNA sections containing candidate genes like those for serotonin and dopamine production contributing to its heritability
• The dopamine hypothesis for schizophrenia has mixed support, with some researchers criticizing it for emphasizing the role of dopamine too much
• The use of neural correlates to explain schizophrenia is limited by its correlational nature, which does not account for the 'third variable problem'
• Psychological explanations for schizophrenia involve abnormal family communication styles, mixed messages, and high levels of expressed emotion as contributory factors in its development and maintenance
• The schizophrenogenic mother, double-bind theory, and high levels of expressed emotion are psychological factors that contribute to the development of schizophrenia
• Dysfunctional thought processes, including metarepresentation and central control, are linked to the development of schizophrenia
• Metarepresentation dysfunction in schizophrenia can lead to paranoid delusions due to the inability to differentiate between one's own thoughts and others'
• Central control dysfunction in schizophrenia can result in derailment in speech due to the inability to suppress automatic associations that each new word brings
• Dysfunctional thought processes and faulty central control skills are implicated in the development of schizophrenia, as demonstrated by research findings
• Dysfunctional thought processing can explain the indirect, proximal causes of schizophrenia, but not the distal causes
• Psychological explanations for schizophrenia are limited in their ability to explain the origin of the disorder
• A comparison between biological and psychological explanations for schizophrenia reveals weaknesses in psychological explanations
• Psychological explanations do not accommodate biological factors that can explain the distal origins of schizophrenia
• Psychological explanations may be best suited for explaining the proximal causes of schizophrenia
• Family-based explanations for schizophrenia lack support and may place undue blame on families and caregivers
• Psychological explanations for schizophrenia may increase blame on families and caregivers, impacting family dynamics
• Biological therapies for schizophrenia include drug therapy