schitzophrenia whole topic summary

What is the prevalence of schizophrenia?

Schizophrenia affects approximately 1% of the population, with a higher prevalence in men compared to women.

What are the two major classification systems for schizophrenia?

The two primary classification systems for schizophrenia are the ICD-10 (International Classification of Diseases, 10th Revision) and the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, 5th Edition).

What are the positive symptoms of schizophrenia?

Positive symptoms refer to additional abnormal experiences that emerge in individuals with schizophrenia, including hallucinations (perceptions without external stimuli) and delusions (strongly held false beliefs).

What are hallucinations?

Hallucinations are sensory experiences that occur without real external stimuli, affecting any of the senses, but most commonly involve hearing voices.

What are delusions?

Delusions are firmly held false beliefs that contradict reality and remain unchanged even when presented with contradictory evidence.

What are the negative symptoms of schizophrenia?

Negative symptoms involve a reduction or loss of normal functions and behaviors. This includes avolition (lack of motivation) and speech poverty (limited speech productivity).

What is reliability in psychological assessment?

Reliability refers to the consistency or repeatability of a measurement or assessment over time.

What is validity in psychological assessment?

Validity indicates the legitimacy or truthfulness of a claim or measurement, determining whether it truly reflects what it intends to assess.

Whose research highlights a lack of reliability in schizophrenia diagnosis?

Cheniaux et al. studied 100 patients, finding significant discrepancies between two psychologists' diagnoses. One psychologist diagnosed 26 patients using DSM criteria but 44 with ICD criteria, while the other diagnosed 13 with DSM and 24 with ICD.

Who found evidence for comorbidity in schizophrenia?

Buckley discovered that 50% of patients with schizophrenia also experience depression, while 47% have substance abuse issues.

Why is symptom overlap considered a weakness in diagnosis?

Symptom overlap may suggest that schizophrenia and other disorders, such as bipolar disorder, could represent variations of the same underlying condition.

Who conducted research on gender bias in schizophrenia diagnosis?

Cotton et al. researched gender bias, finding that women typically have closer social relationships, which provide them with more support, potentially leading to better functioning and diagnostic validity.

Who researched cultural bias in schizophrenia diagnosis? Provide an example.

Escobar examined cultural bias, noting that Afro-Caribbean individuals in the UK are ten times more likely to receive a schizophrenia diagnosis than those living in Afro-Caribbean countries—suggesting that cultural perceptions of symptoms could influence diagnoses.

What did Gottesman find regarding family prevalence of schizophrenia?

Gottesman revealed that having two parents with schizophrenia leads to a 46% concordance rate for the disorder in their children, while one affected parent results in a 13% rate and siblings exhibit a 9% rate.

What did Joseph find about the concordance rates of twins?

Joseph's research indicated that monozygotic (MZ) twins have a 40% concordance rate for schizophrenia, while dizygotic (DZ) twins have only a 7% concordance rate.

Who conducted adoption studies on schizophrenia, and what were the findings?

Research by Tienari, involving 164 adoptees with schizophrenic mothers, found that 11% received a diagnosis of schizophrenia, compared to only 2% in a control group of 197 adoptees.

What are neural correlates?

Neural correlates are specific patterns of brain activity linked to particular experiences or symptoms associated with schizophrenia.

What is the original dopamine hypothesis of schizophrenia?

The original dopamine hypothesis posits that an excess of dopamine activity leads to positive symptoms in schizophrenia, characterized by an increased number of dopamine receptors and heightened binding of dopamine.

What is the updated dopamine hypothesis?

The updated dopamine hypothesis, as proposed by Davis et al., suggests that abnormal dopamine activity in the mesolimbic pathway contributes to positive symptoms, while deficits in the prefrontal cortex are associated with negative symptoms.

What did neural imaging research by Patel et al. reveal?

PET scans conducted by Patel et al. found reduced dopamine levels in the dorsolateral prefrontal cortex of individuals diagnosed with schizophrenia.

What evidence supports the role of genetic vulnerability in schizophrenia?

Gottesman demonstrated a correlation between familial similarity and schizophrenia risk, while adoption studies by Tienari and findings of 108 gene variations related to the disorder add to the evidence of genetic factors.

What environmental factors increase the risk of developing schizophrenia?

Morgan found that smoking THC (tetrahydrocannabinol) cannabis during adolescence is a significant risk factor, and Morkved reported that 67% of individuals with schizophrenia experienced at least one childhood trauma, compared to 38% in a matched control group.

What is the original dopamine hypothesis?

The original version of the dopamine hypothesis suggests that hyperactivity of dopamine leads to the manifestation of positive symptoms, and antipsychotics function by reducing dopamine activity.

What is the updated dopamine hypothesis?

The updated hypothesis proposes that hypodopaminergia, specifically reduced dopamine activity in the prefrontal cortex (PFC), is linked to negative symptoms like speech poverty.

How is glutamate connected to schizophrenia?

McGutcheon found elevated levels of glutamate in the brains of individuals diagnosed with schizophrenia, indicating a neurotransmitter imbalance.

What are token economy systems?

Token economy systems are behavior modification techniques that reward patients with tokens for performing desired behaviors, which can later be exchanged for various rewards.

What principles do token economies rely on?

Token economies are based on operant conditioning principles, where secondary reinforcers (tokens) are paired with primary reinforcers (rewards) to encourage positive behavior.

What negative effects can institutionalization have on patients?

Institutionalization can lead to patients adopting negative behaviors and habits due to the environment of long-term hospitalization.

What are Matson's three categories of institutionalized behavior?

Matson identified three categories of institutionalized behavior: personal care, condition-related behavior, and social behavior.

What did Ayllon & Nazrin discover in their study on token economies?

Ayllon & Nazrin studied a ward of schizophrenic women and found that implementing a token reward system significantly increased the performance of desirable tasks.

What was the focus of Glowacki et al.'s study?

Glowacki et al. conducted a meta-analysis of seven studies assessing the effectiveness of Token Economy Systems (TES) and found a reduction in negative symptoms.

What limitation was noted regarding Glowacki et al.'s study?

Glowacki et al.'s study faced concerns due to its small sample size, indicating a potential bias in published findings, suggesting that negative results may be overlooked.

What ethical concerns exist surrounding research on token economies?

Ethical issues arise when implementing token economies if patients feel their personal freedoms are restricted, particularly as those with severe symptoms may experience a loss of small pleasures.

What is the interactionist approach in the diathesis-stress model?

The interactionist approach posits that both vulnerability (diathesis) and external stressors are necessary to trigger the onset of schizophrenia.

What did Meehl propose about the diathesis-stress model?

Meehl theorized that vulnerability arises from the presence of a specific gene, the 'schizogene,' such that individuals without this gene do not develop the disorder, regardless of stress.

What is the modern understanding of schizophrenia?

Modern research, such as Riptake's findings, indicates that schizophrenia is polygenic, suggesting that various genetic factors interact with dopamine imbalances and environmental influences to predispose individuals to the disorder.

How does cannabis use relate to the development of schizophrenia?

Research indicates that cannabis use, particularly THC, increases the risk of developing schizophrenia by seven times.

What did Tienari's research reveal about the factors contributing to schizophrenia?

Tienari found that high levels of expressed emotion in Finnish mothers correlated with increased rates of schizophrenia in offspring, suggesting that parenting styles impact vulnerability.

Why is the original understanding of schizophrenia formation considered oversimplistic?

The original view simplifies schizophrenia's etiology by attributing it primarily to dysfunctional parenting, while modern studies, like those of Riptake and Houston, underscore the complexity involving genetic and traumatic factors.

Who found that combining treatments enhances effectiveness in reducing symptom severity?

Research by Tarrier et al. demonstrated that incorporating various treatment modalities concurrently is more effective in mitigating symptom severity compared to singular approaches.

Who proposed the concept of the 'schizophrenogenic mother,' and what does it entail?

Fromm-Reichmann introduced the theory of the 'schizophrenogenic mother,' which posits that a cold, rejecting maternal figure can increase the likelihood of their child developing schizophrenia.

What is family dysfunction?

Family dysfunction refers to abnormal interpersonal dynamics within a family unit, characterized by ineffective communication and emotional coldness, leading to high levels of expressed emotion.

Who developed the double bind hypothesis?

Bateson et al. formulated the double bind hypothesis, suggesting that children exposed to contradictory messages from caregivers may develop confusion and maladaptive responses.

What does the double bind hypothesis propose?

The double bind hypothesis suggests that children who receive conflicting messages from caregivers may feel trapped in an ambiguous situation, contributing to psychological distress.

What is expressed emotion?

Expressed emotion (EE) encompasses the degree of negative emotional interactions directed at a patient, including hostility, criticism, and emotional detachment.

What are the two types of dysfunctional thinking identified by Frith?

Frith identified two dysfunctional thinking styles: central control (the ability to suppress automatic responses) and metarepresentation (reflecting on one's own thoughts and behaviors).

What is central control in the context of schizophrenia?

Central control refers to the cognitive ability to inhibit automatic responses, which can lead to disorganized speech when individuals struggle to manage their thoughts and verbal expressions.

What is metarepresentation?

Metarepresentation is the cognitive process of introspective awareness, and its failure can occur in schizophrenia, leading to difficulties in distinguishing between one's own thoughts and external reality.

What did John Reed find that supports family dysfunction in schizophrenia?

Reed's research indicated a correlation between schizophrenia and insecure attachments, revealing that 69% of women and 59% of men with schizophrenia had histories of sexual abuse.

What support does Morkved's research provide for family dysfunction in schizophrenia?

Morkved's findings suggest that a significant proportion of adult patients with schizophrenia report experiencing at least one traumatic event in childhood.

What is the primary issue regarding the scientific support of family-based theories?

The lack of systematic empirical evidence undermines family-based theories for schizophrenia since the concepts of the schizophrenogenic mother and the double bind rely heavily on observational and anecdotal data.

What was John Stirling's research contribution regarding dysfunctional thought processing?

Stirling assessed cognitive performance in thirty individuals with schizophrenia using tasks like the Stroop test, discovering that they took significantly longer to complete the tasks, indicating processing difficulties.

Why are psychological explanations of schizophrenia considered only proximal explanations?

Psychological explanations address current symptoms but do not account for underlying genetic or childhood trauma factors contributing to metarepresentational failures that may predispose individuals to schizophrenia.

What is the ethical concern surrounding parent-blaming in schizophrenia?

Parent-blaming can place undue emotional strain on caregivers, as they often feel responsible for their child's condition, though their role must be carefully explored without unwarranted guilt.

What is the role of dopamine antagonists in schizophrenia treatment?

Dopamine antagonists work by blocking dopamine receptors in the brain to decrease dopamine activity associated with schizophrenia symptoms.

What is chlorpromazine?

Chlorpromazine is a prominent example of a typical antipsychotic medication used in the treatment of schizophrenia.

What are typical antipsychotics?

Typical antipsychotics are medications that primarily alleviate positive symptoms of schizophrenia by binding to and blocking dopamine receptors without activating them.

What did Kapur et al. find regarding the effectiveness of typical antipsychotics?

Kapur et al. found that for typical antipsychotics to be effective, they need to block 60-70% of D2 receptors in the mesolimbic dopamine pathway, although this blockage can lead to side effects.

What is an example of an atypical antipsychotic?

Clozapine is cited as a representative example of an atypical antipsychotic medication, distinguished from typical counterparts.

What is the aim of atypical antipsychotics?

The aim of atypical antipsychotics is to mitigate symptoms with fewer side effects, achieved by temporarily binding to dopamine receptors and allowing for dopamine transmission.

What are the positive effects of atypical antipsychotics?

Atypical antipsychotics enhance mood, cognitive function, and alleviate anxiety and depression through interactions with serotonin and glutamate receptors.

What did Thornley et al. find about the effectiveness of chlorpromazine?

Thornley’s meta-analysis of 13 trials involving 1121 participants indicated that chlorpromazine provided significant improvement in functioning and symptom reduction compared to placebo.

What did Meltzer find about the effectiveness of clozapine?

Meltzer's research established that clozapine is more effective than other atypical antipsychotics, showing efficacy where 30-50% of typical antipsychotics had previously failed.

What issues are associated with the use of antipsychotics?

Research by Healy highlighted significant concerns regarding antipsychotics, pointing out flaws in the evidence of their effectiveness, particularly in the short length of studies and potential publication bias favoring positive outcomes.

What moral dilemma is associated with taking antipsychotics?

Antipsychotics can effectively reduce symptoms for easier management, yet they may induce severe side effects like sedation and emotional numbness, creating ethical dilemmas centered on patient autonomy versus staff convenience.

What are serious side effects of antipsychotics?

Antipsychotics can lead to severe side effects, including Neuroleptic Malignant Syndrome (NMS), evaluation of which shows high fever, delirium, muscle rigidity, and can be fatal. Other side effects include tardive dyskinesia, metabolic syndrome, and extrapyramidal symptoms (EPS), significantly impairing quality of life.