What does the word schizophrenia mean in green?
split mind
- means a split in cognition –> decline in some aspects of cognition and normal in other aspects
what is dementia praecox?
kraepelin’s first encounter with what we call schizophrenia.. onset is in adolescence and its permanent and pervasive functional deficits
who coined the term schizophrenia and what did he coin it by?
eugene bleaker
- hallucinations and delusions he said were secondary
he said primary symptoms are:
- ambivalence
- loosening of associations
- incongruous affect
- autism
what did schneider believe were the criteria for schizophrenia?
first rank symptoms: like audible thoughts, voices arguing, voices commenting, somatic passivity (body is being moved for you), thought withdrawal (someone is pulling thoughts out of your head), thought insertion, thought broadcasting, and delusional perceptions (you think what you’re perceiving is real but the meaning of it is not real)
what are the DSM-5’s criteria for having schizophrenia?
two or more of the following for a significant proportion of time over a ONE MONTH period:
- delusions
- hallucinations
- disorganized speech
- disorganized or catatonic behaviour (odd purposeless movements like hand motions)
- negative symptoms like depression, social isolation..etc..
- Significant social or occupational dysfunction
- signs of the disturbance are present over 6 months
- not due to schizoaffective disorder or exclusively occurring during the course of a mood disorder (i.e. depression)
- not due to substance or general medical condition
- if a pervasive developmental disorder is present, a prominent delusions or hallucinations are present for a month
What are hallucinations? what are illusions?
hallucinations are a perception in a conscious state in the absence of a stimulus
illusions are a misperception of a stimulus
what are chronoceptive hallucinations?
hallucinations caused by drugs like ketamine
what are the most common type of hallucinations in schizophrenia?
auditory hallucinations
what are delusions?
a fixed false belief not in keeping with an individual’s culture
- defined as bizarre when not possible or patently untrue
you can’t convince them out of the delusions
What do negative symptoms of schizophrenia include?
these are deficit symptoms of schizophrenia
- apathy
- anhedonia (lack of enjoyment)
- amotivation (hard to get started on things)
- alogia –> use of fewer words and longer pauses
- poor social function
these contribute to most of the functional impairment than hallucinations or delusions and are less amendable to treatment
what are cognitive symptoms of schizophrenia?
- slow processing speed
- impaired attention
- impaired memory
- impaired executive function
- impaired social cognition
- impaired verbal comrephension
what is the age of onset for schizophrenia?
its a chronic illness with no cute
age of onset for males is 15-25 years old
females its 25-35 years old
what is the clinical course of schizophrenia?
- initial prodromal phase –> attenuated symptoms, include anxiety, sleep disturbance, mood problems, functional decline and precedes psychosis by one year on average… so you see these symptoms a year before psychosis starts .. these are mostly negative symptoms
- first episode of psychosis… treatment results in remission (coming back) of positive symptoms
- residual symptoms: half of patients require social support, negative and cognitive symptoms assist after the positive symptoms
- positive symptoms go away after the course of a lifetime
- but neg symptoms don’t
- the best predictor for further functional impairment is the level of function after the first episode (see where you are after your first treatment)
how is the prognosis for males worse than females?
because their onset of schizo is earlier and they have less of a chance to live their lives and accomplish things
what is the epidemiology of schizophrenia?
1:1 ratio males to females
1 in 10,00 cases annually with a lifetime prevalence of 0.7-1%
what are risk factors for schizophrenia?
- family history –> monozygotic towns have a 40-50% concordance
- urban birth
- first generation immigrant
- winter birth
- prenatal infection or malnutrition
- obstetrical complications
- increasing paternal age
what criteria is the ultra high risk group?
family history of psychosis and at least one of:
- attenuated positive symptoms
- brief psychotic symptoms
- functional decline
50% of developing schizophrenia
the ultra high risk group also show executive dysfunction, working memory problems and the brains of siblings of schizophrenics look like them too
what is the genetics behind schizophrenia?
its a 22q11 deletion - velocardiofacial syndrome (95% of patients who have this will have schizophrenia)
- linkage analysis shows up to 4000 genes involved with it so its polygenic
- candidate genes include those for dopamine receptors and glutamate receptors
what is the neurodevelopment theory for schizophrenia?
says that as you age, developmental tasks become more complex and you can’t keep up and the overwhelming capacy of the brain will cause schizophrenia and a result of prenatal problems like genetic abnormalities
what is the neurodegenerative theory on schizophrenia?
you have a normal brain but then after psychosis your brain becomes abnormal and changes
brain imagining shows:
- increased ventricular size
- temporal lobe asymmetry
- loss of frontal grey matter
- however, no evidence of gloss (Scarring) on pathology
Whats the link between cannabis and schizophrenia?
- thought to be an independent risk factor for schizophrenia
- recent evidence suggests that cannabis use can precipitate psychosis in individuals with specific genetic risk of catechol-oMethyl- transferase (COMT) polymorphism
mutation of this gene cause irregular break down of dopamine and with cannabis can cause schizophrenia
pot heads are 2 times more likely to get schizophrenia
what are other substances that cause symptoms close to schizophrenia?
- amphetamines: agitations,illusions, paranoia during withdrawal and tactile hallucinations (positive symptoms)
- cocaine: agitation, paranoia during withdrawal, visual hallucinations
- phencyclidine (PCP): best substance model of schizo… hallucinations, delusions
what is the dopamine hypothesis in neurochemistry behind schizophrenia?
- initially thought excess dopamine was the case
- amphetamine induces psychotic symptoms
- first generation antipsychotics act as a d2 receptor antagonist
- PET scanning shows increased dopaminergic activity in the striatum, proportional to the severity of psychosis
what is the glutamate hypothesis for schizophrenia?
- antagonists of NMDA-type glutamate receptors induce psychotic symptoms
- individuals with schizo demonstrate a glutamatergic deficit in temporal and stratal regions
