Neurochemical disorders (diseases of NS) Flashcards
What is SZ?
Mental health disorder characterised by continuous or relapsing episodes of psychosis
Can be relapsing & remitting or progressive
Long term disorder that impairs daily functioning
When is the onset of SZ usually?
During adolescence
What is the incidence of SZ?
1% (which is high)
What are the 2 main causes of SZ?
- Hereditary
- Environmental factors
What are the herediatery causes of SZ like?
Strong but not complete
50% risk in identical twins
12% if one parent has the disease
What are the two branches of environmental factors for SZ?
- Foetal or neonatal event
- Childhood/adolescence events
How can a foetal or neonatal event cause SZ?
Hypoxia, infection, stress and malnutrition during pregnancy
Premature birth
How can childhood/adolescence events cause SZ?
- Trauma
- Living in an urban environment
- Social isolation
- Cannabis
Name other risk factors for SZ
- Genetics/family history
- Viral infections
- Lead exposure
- Neurochemical irregularities
- Prenatal exposure to hunger
- Dense living environment
What are the 2 types of SZ symptoms?
- Positive = gain of function
- Negative = loss of function
What are some positive symptoms of SZ?
- Hallucinations
- Agitation
- Delusions
- Disordered thoughts and speech
Gain of function
What are some negative symptoms of SZ?
- Social withdrawl
- Decreased emotional response
Loss of function
What are the neuroanatomical changes with SZ?
- Enlarged ventricles
- Reduced temporal lobe
- Abnormal dendritic fields in the prefrontal area, hippocampus and entorhinal cortex
- Timing of abnormalities not fully determined - neurodevelopmental (present at birth)
What are the two main neurochemical changes with SZ?
- Dopamine
- Glutamate
How does dopamine affect SZ?
- First NT implicated in SZ
- Increased dopamine activity
- Dopamine agoistst produce psychotic symptoms
How does glutamate affect SZ?
- Dopamine antagonists poor at controlling -ive symptoms
- Reduced cortical glutamate
- NDMA antagonists induce psychosis and exacerbate SZ
What pathway does dopamine affect?
The mesocortical pathway
It is related to mood etc
What are the treatments for SZ?
Antipsychotics
Psychological therapies
What are the antispcyhotics used for treating SZ?
D2 receptor antagonists
What do D2 receptors do to treat SZ?
They reduce the levels of dopamine using dopamine antagonists
Can develop a tremor as they aren’t specific to the mesocortical pathway only
What is the most common mood disorder?
Depression
What are the 3 types of mood disorders?
- Depression
- Mania
- Bipolar disorders
What is the incidence level of depression?
8.4% of all US adults experienced at least 1 major depressive episode in 2020
High incidence level, very prevalent in society
How does depression affect you?
Symptoms vary patient to patient
Lasts for weeks or months and affects your daily life
