schizophrenia Flashcards
Schizophrenia
A severe mental illness which involves a break from reality, such as hallucinations. It is an example of psychosis
Positive Symptoms
Experiences or symptoms that are in addition to usual functioning, such as hallucinations or delusions
Negative Symptoms
Experiences or symptoms that involve the loss of usual functioning, such as avolition and speech poverty
Hallucinations
Positive symptom of SZ - sensory experiences of stimuli that do not exist, such as hearing voices or seeing things in a distorted way
Delusions
Positive symptom of SZ - involves having beliefs with no basis of reality, such as being the victim of a conspiracy (paranoia)
Avolition
Negative symptom of SZ - loss of motivation to carry out tasks and results in lowered activity levels
Speech poverty
Negative sympton of SZ - reduced frequency and quality of speech
Subtypes of schizophrenia
Different classifications of SZ (used by the ICD but not the DSM-V), such as paranoid (mainly delusions and hallucinations) or catatonic (immobility and avolition) schizophrenia
DSM-V
System of classification mostly used in the USA. It requires at least one positive symptom for a diagnosis of SZ
ICD-10
System of classification used worldwide, outside of the USA. Recognises subtypes of SZ and does not require any positive symptoms
Reliability of diagnosis
The extent to which different clinicians would agree on diagnosis (inter-rater) or the same clinician would be consistent in their diagnosis of the same patient (test-retest)
Validity of diagnosis
The extent to which diagnoses of SZ are actually correct - for example, is the clinician accidentally diagnosing depression as SZ instead? Does SZ actually exist as one condition?
Co-morbidity
The occurrence of two conditions in the same person - when two are frequently diagnosed together, it questions the validity of diagnosing of them as separate conditions
Symptom overlap
When two different conditions share the same symptom (e.g. avolition in SZ and depression) - it questions the validity of classifying them as separate conditions
Culture bias in SZ diagnosis
The presence of discrimination between cultures/ethnicities in diagnosis, such as the finding that Afro-Caribbean people in the UK/USA are significantly more likely to be diagnosed with SZ than white people
Gender bias in SZ diagnosis
The presence of discrimination between sexes in diagnosis, such as the finding that males are significantly more likely to be diagnosed than females (perhaps due to how they present symptoms differently)
Genetic basis of SZ
The theory that schizophrenia may be due to the influence of specific genes, or a combination of candidate genes
Candidate genes of SZ
The specific genes that are identified as causing, or being associated with, the presence of SZ. Ripke identified 108 separate candidate genes for SZ.
Neural correlates of SZ
Parts of the brain or neurotransmitters (e.g. dopamine) that are linked with the presence of SZ
Family studies of SZ
Schizophrenia is more commonly shared in biologically related relatives with the closer the genetic relatedness the greater the risk (e.g. Gottesman)
Twin studies of SZ
Study the relative contributions of genetics and environment by comparing concordance rates of MZ and DZ twins (e.g. Gottesman)
Adoption studies of SZ
Studies of genetically related individuals that are reared apart (e.g. Tienari)
Dopamine hypothesis
An excess of dopamine in certain regions of the brain is associated with positive symptoms of schizophrenia.
Revised dopamine hypothesis study
Davis and Kahn 1991 proposed positive symptoms of schizophrenia are caused by an excess of dopamine in subcortical areas of the brain , whereas negative symptoms are thought to arise from a deficit of dopamine in area of the prefrontal cortex.