Week Eleven - Psychotic Disorders Flashcards
What do people with psychotic disorders struggle to do? (6)
think clearly communicate properly make good judgements behave appropriately respond emotionally understand reality
Schizophrenia is characterised by?
Major disturbances in thought, emotion and behaviour
- disordered thinking
- lack of emotional expression
- disturbances in movement/behaviour (untidy appearances)
DSM5 diagnostic criteria for schizophrenia?
Two or more symptoms and one symptom should be either 1, 2 or 3 for at least 6 months:
- delusions
- hallucinations
- disorganised speech
- disorganised motor behaviour
- negative symptoms
Positive symptoms of schizophrenia? (2)
Delusions: Firmly held beliefs that are contrary to reality (persecuratory most common)
Hallucinations: Sensory experiences in the absence of sensory stimulation (auditory most common)
Negative symptoms of schizophrenia?
Experience domain
Expression domain
- avolition: lack of interest
- asociality: inability to form close relations
- anhedonia: inability to experience pleasure
blunted: no affect in face/voice
alogia: reduction in speech/intelligence
Other symptoms of schizophrenia?
Disorganised symptoms
- speech
- behaviour
Movement symptoms
- catatonia
- immobility
What are positive symptoms of schizophrenia caused by?
Excess of dopamine in the mesolimbic pathway
- decreasing dopamine in this pathway via an agonist should be effective
What are negative/cognitive symptoms of schizophrenia caused by?
Caused by a shortage of dopamine in the mesocortical pathway
- increasing dopamine in this pathway should be effective
Problems with treating schizophrenia with D2 agonists in the mesolimbic pathway?
Reduces signalling in the mesocortical pathways meaning negative/cognitive symptoms may become worse (at the least they won’t be addressed)
Explain the role of an atypical D2 partial agonist?
Works to reduce dopamine in the mesolimbic, treating pos symptoms - will also act to enhance dopamine signalling, meaning the neg/cog symptoms could be improved as well
- Aripiprazole
The glutamate hypothesis
The predominant ‘go’ NT in the brain is glutamate.
Evidence to suggest implications of glutamate NMDA receptors in Schizophrenia
- post mortem studies
- NMDA receptor agonists can cause psychotic symptoms
Prominent brain area change in schizophrenic patients?
Ventricular enlargement
Results in:
- poor cognition
- poor response to treatment
The pathophysiology of treatment- resistant schizophrenia? (TRS)
Differences between patients with TRS and other schizophrenia (wide spread grey matter)
TRS patients also show reduced connectivity in certain key brain regions
TRS have reduced density of dopaminergic synapses
Neurodevelopment of schizophrenia?
Reduced elaboration of inhibitory pathways and excessive pruning of excitatory pathways leading to altered excitatory-inhibitory balance in the prefrontal cortex
Patients with schizophrenia show what?
Abnormal synaptic communication between neurons in the brain. These occur in several NT systems where disruption in one causes compensatory mechanisms by others
GABA and schizophrenia?
Reduced synthesis and reuptake of GABA has been demonstrated in the prefrontal cortex of patients with schizophrenia
Acetycholine and schizophrenia?
Decreased levels of cholinergic receptors are observed in the HC, thalamus and striatum in patients with schizophrenia
Serotonin and schizophrenia
Prefrontal 5-HT2A receptors have been linked to the pathogenesis of schizophrenia
- activation of these induces psychosis in humans
Inflammation and schizophrenia?
Neuroinflammation is linked to the risk of psychosis and expression of sub-clinical symptoms
Microbiome and schizophrenia?
The gut microbiota is being linked to pathology of schizophrenia
- S patients were dominated by greater number of microbiome species
- had greater abundance of lactic acid bacteria
Environmental factors that are linked to development of schizophrenia?
Prenatal exposure to viral infections
Poor prenatal nutrition
Adverse obstetric events
Cannabis smoking during adolescence (increases up to 3x)
Genetic factors and schizophrenia?
Greater risk of development if relatives are diagnosed.
There are susceptibility genes
- D2 receptor genes
- calcium channel proteins
- immunity genes
Twin study and schizophrenia?
Early onset schizophrenia may have stronger genetic component of risk that other subtypes of schizophrenia
What is schizoaffective disorder? (what are the 2 types)
Symptoms of both schizophrenia and mood disorder (eg bipolar) - hard to diagnose and often misdiagnosed (no tests)
Bipolar type: episodes of mania and major depression
Depressive type: only depressive episodes
Symptoms of schizoaffective disorder?
delusions depression hallucinations no personal care mania speech problems trouble at school/work
Causes of schizoaffective disorder? (4)
Genetics: May inherit a tendency to get features linked to schizoaffective disorder from parents.
Brain chemistry/structure: Problems with brain circuits that mediate mood and thinking.
Environment: Viral infections or highly stressful situations could play a part in getting schizoaffective disorder if you’re at risk for it.
Drug use: Taking mind-altering drugs.
Treatments of schizoaffective disorder?
Medication (antipsychotics or SSRI’s - for mood issues)
Psychotherapy
Skills training
ECT
What is schizophreniform disorder?
type of psychotic illness with symptoms similar to those of schizophrenia, but lasting for less than 6 months.
- same symptoms as others but lasts less than 6 months
type of “psychosis” in which a person cannot tell what is real from what is imagined. It also affects how people think, act, express emotions, and relate to others.
Causes of schizophreniform disorder?
Genetic, brain structures (same as schizoaffective)
Environment: poor relationships/stressful events
Treatment for schizophreniform disorder?
Medication: antipsychotics
Psychotherapy
If symptoms don’t improve - most likely to have schizophrenia
What is brief psychotic disorder?
sudden, short period of psychotic behaviour, often in response to a very stressful event, such as a death in the family. Recovery is often quick – usually less than a month.
- Brief psychotic disorder with obvious stressor
- Brief psychotic disorder without obvious stressor
- Brief psychotic disorder with postpartum onset: women only
Symptoms of brief psychotic disorder?
Same as other forms of schizophrenia
Causes of brief psychotic disorder?
Genetic
Poor coping skills
Is a rare disease - people with antisocial personality are more likely to experience
Treatment for brief psychotic disorder?
Medication: antipsychotics
Psychotherapy
What is delusional disorder?
having a delusion (a false, fixed belief) involving a real-life situation that could be true but isn’t, such as being followed, being plotted against, or having a disease.
- lasts for at least 1 month
- cant be convinced its not true
When do we diagnose delusional disorder?
When it is the only mental health issue a person has.
Symptoms of delusional disorder?
Non-bizarre delusions are the key feature
- no other similar features like that seen in the other forms of schizophrenia
What is paraphrenia?
It starts late in life, when people are elderly.
Paraphrenia is characterised by an organised system of paranoid delusions with or without hallucinations (the positive symptoms of schizophrenia) and without deterioration of intellect or personality (its negative symptom).
What is shared psychotic disorder?
his disorder occurs when one person in a relationship has a delusion and the other person in the relationship adopts it, too.
What is substance-induced psychotic disorder?
Caused by the use of or withdrawal from drugs, such as hallucinogens and crack cocaine, that cause hallucinations, delusions, or confused speech.
- usually goes when stop taking drug
Medical conditions that give rise to psychotic behaviour?
Post-ictal psychosis (PIP) happens in some people with epilepsy who’ve had a number of seizures in a row.
Myxedematous psychosis may happen when your thyroid gland doesn’t work well, known as hypothyroidism (may have hallucinations, delusions)
Female Hormone Shifts may induce psychotic symptom (menstruation induced psychosis).
