Schizophrenia Flashcards
What was eugen bleuler’s original concept of schizophrenia?
Eugen Bleuler
- could emerge at later age→ not always deteriorating
- first to use term schizophrenia
- characterized by disorganization of thought processes
- fundamentally a neurological disfunction
- considered as group of disorders
—>broader definition
Describe hallucinations in schizophrenia?
Hallucinations→ not stimuli is present, but sensory perceptions
- continuum from illusions to hallucinations
- difference is in how the illusions stuck with people with schizophrenia
Can occur in all sensory modalities→ Visual, olfactory, tactile, somatic, gustatory
- Audible thoughts→ echoing of your thoughts by someone else
- voices conversing about patient
- voices commenting on your behavior
- somatic passivity experiences→ something happening to your body but cannot find the cause
- ex: x ray traveling through my body
–>misattributions
What are delusions and their different forms in schizophrenia?
Delusions→ false belief based on an incorrect inference
- firmly believed despite contradictory evidence
- ex: I am the king of England
—>also common in schizotypal PD and prodromal schizophrenia
Different forms
- controlled by outside force→ someone controlling their actions
- Grandiose delusions
- Delusions of jealousy→ my loved ones are plotting against me
- Nihilistic delusions→ the world or around us or oneself do not exist
- Persecutory delusions
- Delusions of reference→ other person is communicating with you via different means (newspaper, social media post)
- Somatic delusions→ someone change my hand
- Thought withdrawal→ thoughts are suddenly vacuumed
- thought insertion→ someone else is putting their thoughts in the patient’s mind but not their own thoughts
- Thought diffusion/broadcasting→ made public for other people
What is the formal thought disorder in schizophrenia and its different manifestations?
Formal Thought disorder-> speech impairment disorder
- derailment→ loose associations
- word salad→ producing recognizable but jumbled words/ extreme end of derailment
- alogia→ not meaning in speech
- neologism→ words invented or giving new meaning to existing words
- blocking→ stop talking in middle of words or thoughts
- illogical thinking
What are the affective impairment present in schizophrenia?
Anhedonia→ external flat affect
- sometimes hard to differentiate with MDD
- can be different internally
Inappropriate
- can talk about difficult things while laughing
- social difficulty
Problems perceiving others’ emotions
What are the different psychomotor disturbances that can be present in schizophrenia?
Catatonia→ behavior that is not link to external environment
- Uncommon in modern schizophrenia
- catalepsy/waxy flexibility→ conscious but engaging with environment, people could move their body
- stupor→ do not respond/ insensitivity to the environment
- posturing
- mutism
- catatonic excitement→ purposeless actions/ agitation
- catatonic negativism→ resisting being moved
- echolalia→ repetitions of sounds or words
- echopraxia→ mimicking a movement over and over again
What is the difference between positive and negative symptoms in schizophrenia?
Positive→ defining features of psychosis
- presence of symptoms that should not be there
- hallucinations, delusions, inappropriate affect
- respond better to medication
–>tend to decrease with age
Negative→ absence of something that should be there
- blunted affect, alogia (decrease speech output), avolition (diminished motivated self directed behavior)
- harder to treat
—>less used because few people have only negative symptoms
Can also add cognitive symptoms
-problem with attention
- impaired working memory
- longer term verbal memory deficits
What are the DSM-5 criteria to be diagnosed with schizophrenia?
In DSM-5, need two of the following:
- Delusions*
- Hallucinations*
- Disorganized speech and behavior*
- Grossly disorganized or catatonic behavior
- Negative symptoms
- Level of functioning markedly lower than prior to onset
—>at least one must be in the three first rank symptoms (*)
- Symptoms present for six months and include at least one month of active symptoms
- Unipolar, bipolar depression, schizoaffective disorder ruled out
- Not attributable to substance
What is the schizoaffective disorder?
Def→ schizophrenic features and severe mood disorder
- mood disorder can be unipolar or bipolar
- BUT must currently meet criteria for depressed mood
- Delusions or hallucinations for 2 or more weeks in the absence of a
mood episode during lifetime duration of illness
- BUT diagnosis of major mood episode present for the majority of illness
—>need to take lifetime history of the patient to diagnosis it
Why is schizoffective disorder a controversial diagnosis?
Very controversial diagnosis
- poor reliability
- not clearly a distinct diagnosis
- prognosis somewhere is between schizophrenia and mood disorders
- better prognosis than schizophrenia
What is the epidemiology of schizophrenia?
Lifetime prevalence→ 0.7-1%
- decrease over time
Sex differences
- M:F of 1.4:1
- women tend to present more with diagnosis of depression
- estrogen might be protective against schizophrenia
Age of onset
- early 20s
- late onset more common in women (after menopause)
Course-> only 20-30% can maintain a life and a job
How does schizophrenia in childhood manifest itself?
Schizophrenia in childhood→ under 13yo
- extremely rare
- more common in boys
- onset is gradual
- characterized by early speech and language problems
- delayed motor development and poor coordination
- very low % of remission when onset in childhood
- more genetic loading
What is the course of schizophrenia like?
Usually pretty negative course
- only 20-30% able to live indecently and maintain job
- 20-30% have persistent moderate symptoms but out of institutions
- rest (50%) keep severe impairment the rest of their lives
- only 40% had one or more periods of recovery
- poorer clinical and functional prognoses than other disorders
Worst outcome in industrialized countries
Life expectancy
- live 20years less than non schizophrenic person
- suicide is main contributor
What are some good prognostic indicators in schizophrenia?
Good
- Good premorbid adjustment (e.g., had friends)
- Acute onset (less than 1 month)
- Manic and depressive symptoms
- Confusion or disorientation during psychosis
- Family history of mood disorder
What are some bad prognostic indicators of schizophrenia?
Bad
- Poor premorbid adjustment
- Insidious, gradual onset
- Negative symptoms (esp. blunted affect)
- Family history of schizophrenia
- In some studies a lower IQ
What is the link between substance abuse and schizophrenia?
Substance abuse very common (47% met lifetime SUD)
- alcohol and nicotine especially
- could be self medication→ show improved cognitive functions
- nicotine improves memory and attention even in control participants
- substances may also trigger schizophrenia (early cannabis)
What are the rates of suicide in individuals suffering from schizophrenia?
High rates of suicide
- about 20% will attempt at least once
- 5% succeed
- especially true for young men in early 20s
- those with best premorbid functioning more at risk for suicide–> might be because change is more important
Is there a genetic risk for schizophrenia?
Genetics-> Suggests some added genetic component of schizophrenia
—>BUT not deterministic but probabilistic
Twin studies→ higher concordance for Mz twins than Dz twins
- concordance in Mz→ 28%
- concordance in Dz→ 6%
Fischer’s study→ children of mz twins WITHOUT schizophrenia have genetics risk but no environmental risk
- higher risk than controls suggesting genetic component
—>BUT little evidence for single-gene effects
What is an endophenotype and a gene-endophenotypes-phenotypes example in schizophrenia?
- Endophenotype→ intermediate step between microscopic genes and nerve cells and the experiential and psychological phenotype
- must segregate with illness in the population
- must be heritable
- must not be state-dependent (i.e., manifests whether illness is active or in remission)
- must co-segregate with illness within families
- must be present at a higher rate within affected families than in the population
- must be amenable to reliable measurement, and be specific to the illness of interest
Example-> eye tracking abnormalities
- stable over time
- also present in 1st degree relatives of people with schizophrenia
What are some risk factors of schizophrenia?
Risks factors
- SES
- Advanced paternal age
- Birth complications
- Seasons of birth
- Malnutrition in pregnancy (increase risk by 2 in Dutch Hunger Winter)
- Cannabis
What is the link between SES and schizophrenia?
SES and ethnic minorities more at risk
- social causation VS social selection
- social causation-> immigrants more likely to develop schizophrenia but not more important genetic loading
- immigrants to uk or Netherlands from Caribbean and Africa
- if more minoritized, higher risk
—>could be due to stress
What could be an explanation for why advanced paternal age might be a risk factor for schizophrenia?
- could be mutations in sperm?
- could also be that men with schizotypique or prodromal schizophrenia marry later and have children later–>more evidence for that
What is the link between birth complications/ season of birth and schizophrenia?
Schizophrenic pts more likely to have experienced birth complications
- Breech delivery, prolonged labor, umbilical cord around neck
- All can result in hypoxia/ anoxia (oxygen)
- anoxia at birth can also result in dopamine supersensitivity
Prenatal exposure
- viral infections→ influenza epidemic in 2nd trimester
- antibodies during pregnancy→ herpes, rubella, influenza
Season of birth-> Small but significant→ late winter to early spring
- 5-15% increase
- stronger when further from equator
- second trimester of pregnancy would have been during presence of virus
What is the effect of cannabis on schizophrenia?
People with schizophrenia 2x more likely to smoke weed
- predict onset of Schiz
- THC increase DA synthesis
-also more loss of gray matter over time
What is an important neurodevelopmental task of the 2nd trimester of pregnancy that could be essential in schizophrenia?
Neural migration→ important task of 2nd trimester/ neurons moves to cortical surface
- disruptions can affect neural connectivity, cortical connectivity, decrease gray matter and even cell death
- less organized neurons in overall cortex
- more white matter than gray matter
What is the effect of schizophrenia on whole brain volume?
Whole brain volume
- decreased whole brain volume in schizophrenia/ especially hippocampus
- progressive loss of gray matter over time
- not a result of treatment→ even present in recent-onset
Not a symptom of the disease
- same matter loss in Mz twins of schizophrenics
- might be neurodevelopmental process genetically determined
What is the dopamine hypothesis in schizophrenia?
Antipsychotic drugs→ work on DA system
- bloc D2 receptors
Cocaine, amphetamines boost DA activity
- can result in psychosis, paranoia
CSF studies with people with schizophrenia→ no direct evidence of more dopamine
- could be the DA receptors rather than levels of DA
—>best evidence is→ excess DA transmission in striatum and reduced DA in frontal lobes
What was the Parker’s study on Working memory in schiphrenic patients?
Tested Working memory deficits in schizophrenic, HC, Bipolar
- Were presented with a target on a stimulus display board
- then delay period with distractor tasks
- then ask to perform a memory guided movement towards previous target
Results-> Deficits in WM is unique to Schiz
- also in schizotypal symptoms
- present when ill and healthy
- evident in1st degree relatives
Which brain region is implicated in the deficits in working memory in schizophrenic patients?
Dorsolateral prefrontal cortex (DLPFC)→ highly regulated by DA
- implicated in working memory bad in schizophrenia
- cognitive deficits consistent in schizophrenia
- Park’s study→ WM deficits seems unique to Schizophrenia
What is aberrant salience in schizophrenia?
Aberrant salience→ Increased DA may cause pts to attend more to
irrelevant stimuli
- harder to gate info for patients
- struggle to make sense of everyday experiences
Failure to respond to meaningful reward cues
- anhedonia and negative symptoms
- might be because of DA abnormalities
Abnormal movements
- upper-limb dyskinesias, oral facial
- hyperactive DA pathways
What is the consequences of expressed emotion on schizophrenia?
Deinstitutionalization of patients
- went home to families or lived solitary lives
- worst outcome for people going home to their family
Especially those in family with high EE (expressed emotion)
- Criticism, Hostility, Emotional overinvolvement
- shown to predict relapse
- when EE is lowered→ relapse rates decrease
—>seems that encourage patients to dig in into their odd thoughts
–>also worst outcomes in depression and BD BUT protective for BPD
What is are other form of schizophrenia spectrum disorders?
Delusional Disorder-> Another form of psychotic disorder
- symptoms restricted to one or more delusions
- some nonprominent hallucinations might accompany the delusions
- later onset than schizophrenia and less impairment
Biref psychotic disorder-> less than 1month
- then return to normal functionning
Schizophreniform disorder-> symptoms of schizo for 1month to 6month
- then return to normal functionning
Cluster A PDs-> not full blow psychotic episodes
What are the cognitive deficits in schizophrenia?
Sensory information processing
- slower in processing of visual stimuli
- sensory gating
Higher level cognition
- verbal and spatial memory
- abstract reasoning
- executive functioning
Social cognition
What is the strongest genotypic predictor of schizophrenia?
22q11.2-> missing DNA in the 22nd chromosome
- 30% will develop schizophrenia or another psychotic disorder
What does Diffusion tensor imaging (DTI) measure?
strenght and direction of water diffusion in white matter
- can report Functional anisotropy-> how water flow in the brain
- schizophrenic patients-> show functional anisotropy reductions
–>might be due to axonal damage
