schizophrenia- 3 Flashcards
outline the classification of schizophrenia
the process of describing its symptoms, 2 systems of classification- ICD-10, DSM-5, used as diagnostic tools
outline positive symptoms
symptoms that reflect an excess or distortion of normal psychological functioning- hallucinations and delusions
outline hallucinations
sensory experiences of stimuli that either have no basis in reality or are distorted perceptions of reality
-can be experiences in relation to any sensory modality, mainly auditory
outline delusions
bizarre beliefs that seem real to an individual but are at odds with reality
-must be idiosyncratic, incorrigible, at odds with reality and be believed with certainty
outline negative symptoms
deficits of normal emotional responses or other thoughts processes
outline avolition
reduction in interests or desires as well as an inability to initiate or persist in any goal-directed behaviour
-neglecting routine activities such as work, hobbies and social activities
outline speech poverty
a reduction in the amount of and/or quality of speech
-may reply sparsely, answers will lack spontaneous content or may fail to answer at all
compare the systems of classification
both consider the positive symptoms as more important- cannot be diagnosed with schizophrenia if only negative are present
-DSM requires a 6 month period of active symptoms for diagnosis while ICD only requires one
how to measure the validity of diagnosis and classification of schizophrenia
descriptive validity- assess whether the set of symptoms is distinct from other conditions, if symptom overlap occurs, perhaps schizophrenia is not an entirely separate condition
how to measure the reliability of the diagnosis and classification of schizophrenia
inter-rater reliability- two separate clinicians diagnose the same group of patients, if there is a strong correlation between each diagnosis then diagnosis is reliable, suggesting the systems of classification are also reliable
limitation- reliability and validity of diagnosis of schizophrenia- research challenge
Rosenhan- psychiatric hospitals could not distinguish patients with genuine schizophrenia from pseudopatients (confederates pretending to hear voices but otherwise acting normally)
-hospitals were inconsistent in their diagnosis (83 patients initially diagnosed with schizophrenia were later reclassified as pseudopatients) this suggests their diagnoses lacked reliability
- given that reliability is a necessary precondition for validity, the failure to reliably diagnose these patients also suggests that the process of diagnosing patients with schizophrenia is also invalid
-since 1973, the systems of classification and process of diagnosing schizophrenia has changed substantially
-Rosenhan’s research may lack temporal validity, meaning it may not tell us much about the reliability and validity of the classification and diagnosis of schizophrenia today
limitation- reliability and validity of classification and diagnosis of schizophrenia- socially sensitive
Sieber and Stanley- socially sensitive research is research that has social consequences either for the research’s participants or for social groups connected to the research
- clear social consequences to researching the validity and/or reliability of schizophrenia as a diagnostic construct- possible consequence might be that people lose confidence in the profession of psychiatry, and are less willing to accept help- this might lead to mentally ill people being left untreated
-research into the validity of schizophrenia may be socially beneficial, If such research furthers our understanding of mental illness, this information could inform the treatment of mentally ill people
what is symptom overlap
when disorders share common symptoms, many positive and negative symptoms of schizo are also found in depression and bipolar
limitation- diagnosis and classification of schizo- symptom overlap
Konstantareas and Hewitt-compared symptoms of 14 autistic patients and 14 patients with schizo, none of the schizophrenics had autism symptoms, but 7 of the autistic participants had symptoms of schizo
- overlap between the symptoms of schizophrenia and autism, demonstrating the issue of symptom overlap for the classification of schizophrenia
- undermines the validity of the classification of schizophrenia, if the symptoms of schizophrenia overlap with other disorders, then perhaps schizophrenia is not a condition that is real and distinct from the other conditions
-could lead to invalid and unreliable diagnoses
what is co-morbidity
when two or more conditions co-occur, e.g. depression and substance abuse
limitation- diagnosis and classification of schizophrenia- co-morbidity
Sim et al- 32% of patients hospitalised with schizophrenia had an additional mental health disorder
-co-morbidity is common with people with schizophrenia
- this threatens the validity of the diagnosis of schizophrenia, as if conditions frequently co-occur, then they may actually represent a single condition
-systems of classification may be incorrect in distinguishing schizophrenia from other disorders (making them invalid)
what is gender bias (in diagnosis of schizo)
when validity of diagnosis is dependent on gender of the patient
limitation- diagnosis of schizo- gender bias
Longenecker - reviews studies of the prevalence of schizophrenia, found that since the 1980s, men have been diagnosed more with schizophrenia than women
-could be an issue of gender bias within the diagnosis of people with schizophrenia, as there is a clear gender difference in these findings
-systems of classification are biased, so more effective at describing the presentation of schizophrenia in men than women, leading clinicians to more effectively diagnose men than women
- might be more likely if female patients typically function better than men, leading them to mask the negative symptoms of schizophrenia more effectively
- also possible that schizophrenia is simply a condition that occurs more in men, meaning the systems of classification do validly describe schizophrenia and there is no issue with the validity or reliability of the diagnosis- If true, gender bias is not an issue for the diagnosis and classification of schizophrenia
what is cultural bias (in the diagnosis of schizo)
tendency to over diagnose poeple from certain cultures and perhaps under diagnose poeple from other cultural backgrounds
limitation- diagnosis of schizophrenia - cultural bias
Cochrane- rate of schizophrenia in the West Indies and in Britain is very similar, but people of Afro- Caribbean backgrounds in the UK were seven times more likely to be diagnosed with schizophrenia than White British people in the UK
-similar rates in the two countries suggest there is nothing innate to people of an Afro-Caribbean background that makes them more likely to develop schizophrenia
- high diagnostic rates in the UK may be the result of a tendency for British clinicians to over-diagnose the condition in the population, indicating a culturally biased approach to diagnosis
-this might result from culturally biased attitudes of British clinicians, who may distrust the honesty of self-reported symptoms by Black British patients
- also possible the context of being black and British may result in a stressful environment, which perhaps results in more people from an Afro-Caribbean background developing schizophrenia in Britian- If true, this would mean the diagnosis of schizophrenia is not affected by cultural bias, making it valid and reliable
outline the genetic exp for schizo
early research (meehl) suggested a single gene was responsible for schizo- schziogene
-schizo has a genetic basis- many candidate genes, polygenetic
-one candidate gene is the COMT gene- involved in regulation of dopamine, provides genetic basis for dopamine hypothesis
outline the dopamine hypothesis
positive symptoms of schizo are caused by hyperactivity or dopaminergic neurones in the reward pathway
-due to high levels of dopamine released and high levels of D2 receptors
outline the revised dopamine hypothesis
negative symptoms caused by hypoactivity of dopaminergic neurones in prefrontal cortex
outline neural correlates
aim to identify abnormalities in structure and function of regions of the brain that correlate with positive and negative symptoms
-auditory hallucinations- reduced activity in superior temporal gyrus (responsible for recognition of inner speech)
-avolition- reduced activation of ventral stratum (responsible for anticipation of reward)
limitation- bio exp for schizo- reductionism
biologically reductionist -seek to explain complex phenomena in terms of the contribution of features of our biology, such as our genes
- simplifies and ignores the interaction with other relevant levels of explanation, such as the role of stressor in our environment (diathesis-stress model)
- at odds with holistic explanations, which consider the role of all relevant factors and avoids the oversimplification resulting from reductionist explanations
- entirely biological explanation can only offer a partial explanation of the disorder
strength- genetic exp (bio exp) for schizo - research support
- Joseph- meta-analysis of schizophrenia twins
-MZ twins was 40.4% and 7.4% for DZ twins
-higher concordance rates for MZ twins indicate that genetics do play a role in causing schizophrenia - However the concordance rates for MZ twins were not 100% -although schizophrenia clearly has a genetic basis, it is not entirely a genetic condition
-suggests environmental factors also play a role in explaining schizophrenia, meaning the genetic explanation can only offer a limited explanation for schizophrenia - support is limited by its reliance on twin studies- cannot ensure equal environmental treatment of DZ twins
-meta-analysis- large representitive samples, generalisable to wide population
strength- dopamine hypothesis (bio exp) for schizo- research support
antipsychotics which block the action of dopamine (dopamine antagonists) have been used to effectively treat the positive symptoms of schizophrenia
- users of dopamine agonists, such as cocaine and amphetamine, experience symptoms like hallucinations and delusions that mirror the positive symptoms of schizophrenia
-only provides support for the dopamine hypothesis, no support or challenge to the revised dopamine hypothesis
strength- neural correlate (bio exp) for schizo- research support
Allen, using fMRI - compared to controls, schizophrenic patients had abnormally low activity in the superior temporal gyrus-associated with identification of inner speech
- provides clear evidence that abnormalities in the superior temporal gyrus are linked to the auditory hallucinations of schizophrenia
-only provides evidence of a correlation, we cannot necessarily assume the direction of causation
-fMRI-produces images of a very high spatial resolution, can be confident of specific area
what are antipsychotics
class of medication used to treat many symptoms of schizophrenia
-two groups- typical and atypical
-dopamine antagonists, block D2 receptors without activating them
what are the side effects of antipsychotics
extrapyramidal symptoms, weight gain, sex drive loss, possibly agranulocytosis (ineffective production of white blood cells)
what are extrapyramidal symptoms and why do they occur
undesirable movement problems e.g. spasms and motor restlessness
-occur since dopamine antagonists block D2 receptors in areas of the brain controlling movement
-atypicals causes fewer since they only temporarily occupy the receptors so dont disrupt functioning as much
outline how atypicals can have beneficial effects on affective symptoms and cognitive deficits
clozapine- serotonin agonist for 5-ht1a receptor, produces beneficial effects on mood and anxiety
strength/limitation- drug therapies for schizo- research
Crossley-meta-analysis to compare the effectiveness of typical and atypicals -equally effective in reducing positive symptoms but atypicals lead to more weight gain and produce more extrapyramidal symptoms
-both typical and atypical antipsychotics can be equally useful in treating some of the symptoms of schizophrenia
- both cause side effects, resulting in a reduction of compliance with taking the medication, making the drug therapies less useful for helping people with schizophrenia
- different profile of side effects means that psychiatrists need to carefully consider the relative advantages and disadvantages when deciding what to prescribe patients
-meta-analysis- large sample size, more externally valid
limitation- drug therapies for schizo- limited treatment
2015 meta-analysis of studies examining the effectiveness of typical and atypical antipsychotics - none of these medications provided clinically significant benefits for negative symptoms
-drug therapies only offer a limited treatment for schizophrenia
- meta-analysis- large sample size, more externally valid
- causes of the negative symptoms are more complex than the positive ones or that they are rooted as much in psychological factors as in chemical changes within the brain cells
-demonstrates the importance of avoiding a reductionist approach to the treatment of schizophrenia, which focuses only on one level of explanation
outline the family dysfunction exp for schizophrenia- psychological exps
explains schizo in terms of problematic patterns of behaviour within the family
outline high levels of expressed emotion
type of dysfunctional family process, intensity of negative emotion expressed by family member
-hostility, emotional over-involvement, critical comments
- known predictor of relapse- leads to decline in mental health
-stress caused by EE may lead to development of schizo (diathesis-stress)
what is hostility (high levels of EE)
generally negative attitude directed at patient- results from familys belief that disorder is controllable and patient chooses not to get better
what is emotional over-involvement (high levels of EE)
over-protective style of engagement towards patient, intrusive and controlling
-needless self-sacrifice by family
what are critical comments (high levels of EE)
complaints directed at patient, accusations of laziness and selfishness
outline dysfunctional thought processing- decision making- as a cog exp for schizo
dysfunctional form of decision making- jumping to conclusions- reaching rapid decisions on uncertain evidence
-can explain delusions- more easy to hold beliefs that are at odds with reality
outline dysfunctional thought processes- metarepresentation- as a cog exp of schizo
disruption of a persons ability to identify inner speech from outer speech
-explains hallucinations- a person may mistakenly believe their own thoughts have an external origin- hearing voices
similarities between family dysfunction exp and cognitive exps-psychological exps
both middle level exps
-both reductionist
-both nomothetic
differences between family dysfunction exps and cognitive exps- psychological exps
social-psychological level (externals impact on internal) of exp vs cognitive level of exp (internal only)
-EE explains onset of symptoms and severity of illness, cog only explains specific symptoms
strength- psychological exps for schizo- real-life applications
both family dysfunction and cog exps have led to the development of successful therapies (family and cbt)
-success of treatments provides support for validity of exps
limitation- psychological exps for schizo (family dysfunction)- socially sensitive
socially sensitive research has potentially harmful social consequences either for participants or people connected to the research
-may lead family members to feel blamed for relatives condition, could lead to caretakers stopping engaging with medical professionals- impacting patients recovery
-doesnt discredit family dysfunction exps- but vital that researchers challenge the blame on family members - careful consideration on communication of findings
limitation- psychological exps for schizo (cog exps) - limited exps
clear links between dysfunctional thought processes and symptoms, but no explanation of what led to development of dysfunctional thought processes
-partial exp for symptoms, other theories needed to explain development of symptoms
-issue with reductionist levels of exp, holistic account needed
what is the aim of token economies
to manage the symptoms of patients being cared for in institutions
how are token economies used in hospitals
patients are given tokens when they complete desirable behaviours, such as washing or exercising, they can then exchange these for rewards, such as food or cigarettes
why are token economies effective
positive reinforcement, the tokens act as a secondary reinforcer meaning the ability to reinforce behaviours is only obtained when they become associated with the primary reinforcer of the reward
-tokens must be given immediately after the behaviour is completed to avoid delay discounting
strength- token economies- research support
schizo patients in Iranian hospital who were randomly allocated to token economy programme had fewer negative symptoms than those in control condition
-use of random allocation allows control for individual differences
-shows token economies can be effective as treatment of negative symptoms
limitation- token economies- ethical issues
use of token economies results in patients less able to manage their symptoms receiving less privileges than those who can
-discrimination- discriminate against those with more severe symptoms as they will find it harder to complete target behaviours
-token economies are therefore not used in modern hospitals
what is the aim of CBTp
to challenge the dysfunctional thinking and behaviour associated with schizo, and reduce the stress caused by the symptoms
outline psycho-education (CBTp technique)
educating patient about their condition using the stress- vulnerability model
- outlines link between thoughts, feelings and behaviours
-can make the illness seem more manageable, reducing stress and helping the patient engage with the therapy
outline cognitive therapy for delusions and or hallucinations (CBTp technique)
explores rationality of patients delusional belief, aiming to changing the beliefs that cause distress
-reality testing experiments- look for evidence to challenge their delusions
outline behavioural skills training (CBTp technique)
agree on behavioural actions for patient to take to reduce stress caused by symptoms
-behaviours are individualised to situation but could include things like controlled breathing
outline the stress vulnerability model
an event is created by a combination of how someone interprets it, feels about it and reacts to it (their interpretations, emotions and behaviours)
strength- CBT for schizo- research support
meta-analysis of 14 studies of CBT involving 1484 patients showed that CBT reduced positive symptoms
-meta-analysis- large samples size, representative and generalisable
-no evidence for help with negative symptoms
limitation- CBT for schizo- methodological issues
supporting studies fail to blind researchers when assessing effectiveness of treatments
- researchers then know what treatment patients are receiving and this could lead to investigator effects
-some studies fail to use control group, meaning improvements could result from individual differences instead of CBTp
what are the aims of family therapy
to improve communication, reduce levels of negative emotion including EE, and help members of the family balance their needs with the need to care for the patient
why is family therapy helpful
families can provide an important source of support, which can be harmful in situations of family dysfunction
what is psychoeducation in family therapy
teaching the patient and family the facts about the illness, its causes, the influence of drug abuse and the effect of stress and guilt
what is communication skills training in family therapy
teaching family to listen, to express emotions in a constructive way and to discuss things
- additional communication skills are taught, such as compromise and negotiation and requesting a time out
strength- family therapy for schzio- research support
randomly allocated 63 poeple with schizo to either have standard drug care or with family therapy, after a year 61% of patients in drug care had relapsed, compared to 33% with family therapy
-effective as additional treatment
-shows long term benefits
-random allocation- difference in relapse can be attributed to use of family therapy instead of individual differences
limitation- family therapy for schzio- research challenge
garety- high levels of relapse in schizo patients without carers and low levels of patients with carers, regardless of whether they were in family therapy
-shows that family plays an important role in care and support of patients but shows family therapy wasn’t helpful in preventing relapse
outline the diathesis stress model in explaining schzio
diathesis makes a person vulnerable to developing schizo but this must interact with a stressor to cause the illness to develop
outline the interactionist approach to treating schizo
CBT and drug therapies- antipsychotics administered to reduce positive symptoms which then allows patients to better engage with CBT
-family therapies and drug therapies - drug therapies administered allowing patient to be well enough to return to care of family, family therapy then helps family better care for patient
strength- interactionist exp for schizo - research support
research on adopted children of 19000 finnish mothers - being raised in family environment with high levels of criticism and low levels of empathy is a risk factor for developing schizo but only when bio mother had schizo
-supports diathesis- stress model
-large sample size, representative and generalisable- only on adopted children
limitation- interactionist exps for schizo- falsifiability
an exp which focuses on only one level of exp are easier to falsify
-more complex interactions and variables making it harder to test empirically- not falsifiable, lacking scientific credibility