Schizophrenia Flashcards
What is schizophrenia?
A type of psychosis, a severe mental disorder characterised by a profound disruption of cognition and emotion so that contact with external reality and insight are impaired. This affects a person’s language, thought, perception, emotions and even their sense of self.
How common is schizophrenia?
Affects 1% of the population at some point in their lifetime
What type of disorder is schizophrenia?
Psychotic disorder
When does schizophrenic symptoms typically begin to show?
It can occur any time in life, but usually occurs late in adolescence or early adulthood. The peak of incidence onset is 25-30 years.
What do we mean by classification in the context of schizophrenia?
Organising symptoms into categories based on which symptoms cluster together in sufferers i.e. what are the symptoms of schizophrenia?
What do we mean by diagnosis in the context of schizophrenia?
Deciding whether someone has a particular mental illness using the classifications. (does someone have the symptoms)
Define positive symptoms
Atypical symptoms that are in addition to regular sensory experience
Define negative symptoms
Atypical symptoms that represent a loss compared to regular sensory experience
Define hallucinations
Disturbances of perception in any of the senses. They are false sensory perceptions that have no basis in reality or are a distorted perception of things that are (positive)
Define delusions
False (irrational) beliefs not based in reality or are a distorted perception of things that are (positive)
Define speech poverty
Limited speech output with limited, often repetitive content. It involves reduced frequency (amount) and quality of speech (negative)
Define avolition
A lack of purposeful, willed behaviour. It is the reduction, difficulty or inability to start and continue with goal-directed behaviour i.e. actions performed to achieve a result. (negative)
Give examples of different kinds of hallucinations
Visual - see something that isn’t there
Auditory - hear something that isn’t real
Give examples of different kinds of delusions
Delusions of persecution – the belief that others want to harm, threaten or manipulate you e.g. the government, aliens.
Delusions of grandeur – the belief that they are an important individual, even god-like and have extraordinary powers e.g. the belief that they are Jesus Christ.
Delusions of control – the belief that their body is under external control e.g. being controlled by aliens or the government (e.g. have implanted radio transmitters).
What do we mean by a classification system of schizophrenia?
A cluster of symptoms
There are two classification systems used to classify and diagnose schizophrenia. For each one, name it and explain what combination of symptoms are required for a diagnosis of schizophrenia.
DSM-5 - America - two of the positive symptoms must be present for diagnosis, but only one if delusions are bizarre or hallucinations consist of a voice keeping up a running commentary on the person’s behaviour or thoughts, or two or more voices conversing together. There must be continuous signs of disturbance for at least 1 month. For a significant portion of the time, one or more major areas of functioning such as work, interpersonal relations or self-care must be markedly below the level achieved prior to onset.
ICD-10 - Europe - two or more negative symptoms are sufficient for diagnosis or one positive symptom.
What do we mean by reliability in the context of classifying and diagnosing schizophrenia?
The level of agreement (consistency) on the diagnosis of schizophrenia by different psychiatrists (inter-rater reliability) across time (test-retest reliability) and cultures. It is also the stability of diagnosis over time given no change in symptoms.
What do we mean by validity in the context of classifying and diagnosing schizophrenia?
The extent to which schizophrenia is a unique syndrome with unique characteristics, signs and symptoms (so whether it measures what it intends to measure). Miss Maiden’s note: this includes whether we can tell the difference between schizophrenia and other mental illnesses and whether we can accurately diagnose someone has having schizophrenia when they do and not diagnose them when they don’t.
Describe evidence that the DSM5 is reliable.
Osario et al. (2019) found inter-rater reliability of +0.97 and test-retest reliability of +0.92 for the DSM5 suggesting the diagnosis of schizophrenia is consistently applied.
Define symptom overlap.
When two or more conditions share symptoms.
Give an example of symptom overlap in the classification and/or diagnosis of schizophrenia
Hallucinations, difficulty concentrating and delusions are a part of bipolar disorder
Explain how this impacts the validity of the classification and/or diagnosis of schizophrenia.
Validity of classification - it seems that schizophrenia does not have enough unique characteristics, signs and symptoms to be distinguishable from other mental health problems.
Validity of diagnosis - therefore there may be misdiagnoses as people may not be accurately diagnosed with schizophrenia when they have it, and not diagnosed when they don’t have it.
Describe evidence that supports the symptom overlap is an issue in the validity of the classification and/or diagnosis of schizophrenia.
Ketter (2005) points out that misdiagnosis due to symptom overlap can lead to years of delay in receiving relevant treatment, during which time suffering and further degeneration can occur, as well as high levels of suicide- so symptom overlap can have serious consequences. Focusing on fixing this issue could save money and lives.
Describe evidence that supports that symptom overlap is not a significant issue in the validity of the classification and/or diagnosis of schizophrenia.
Serper et al. (1999) assessed patients with co-morbid schizophrenia and cocaine abuse, cocaine intoxication on its own and schizophrenia on its own. They found that despite there being considerable symptom overlap in patients with schizophrenia and cocaine abuse, it was actually possible to make accurate diagnoses.