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Mind and brain are two sides of one coin;
Disorders of the mind* are disorders of the brain.
* schizophrenia, depression, anxiety, psychopathy, etc.
Schizophrenia
• Clinical features
• Etiology (cause)– Genetic– Environmental
• Neurobiology & Pharmacotherapy
Clinical features
• Positive symptoms: Characteristics displayed by schizophrenics that are not typical present in healthy individuals.
• Negative symptoms: Absence of characteristics that are typical present in healthy individuals.
–
Clinical features
• Positive symptoms: Characteristics displayed by schizophrenics that are not typical present in healthy individuals. – Hallucinations
– Delusions– Disorganized speech- Socially awkward behavior
• Negative symptoms: Absence of characteristics that are typical present in healthy individuals.
–
Hallucinations: Sample item from Scale for the assessment of positive symptoms
• Have you ever heard voices commenting on what you are thinking or doing?– What do they say?
Delusions: items from Peters Delusion Inventory
Clinical features• Positive symptoms
– Hallucinations– Delusion– Disorganized Speech– Socially awkward behavior (disorganized)
• Negative symptoms*– Poverty of speech– flat affect, apathy, anhedonia– Decreased motor activity
• Cognitive symptoms*– Working memory, attention
A very debilitating disease* non-specific
High Dopamine
Hypofrontality
All ethnic groups/geography
Lifetime prevalence = 1%
First diagnosis at 20 yrs of age
Prodrome at 17 yrs of age
Early detection is key, as delayed
treatment:
- increases brain damage,
- shows less recovery
Some signs present at childhood:
- neuromotor functions
- sociability
- emotions
male
female
10 20 30 40 50 years Jennen-Steinmetz et al 1997
Time course:- positive symptoms are evident in the acute episodes- negative symptoms increase gradually (although they can precede the positive ones, as in the prodrome)
1st acute episode
prodrome relapse residual phase
relapse
Schizophrenia
• Clinical features
• Etiology (cause)– Genetic: – Environmental
• Neurobiology & Pharmacotherapy
Increased risk with closer genetic distance
1
9
17
48
0 20 40 60
1
identical twin
fraternal twin
sibling
generalpopulation
Given that somebody is schizophrenic, what is the likelihood that you will suffer from schizophrenia? (in %)
If biological parent is schizophrenic: 17%
- Age of father (not of mother)- Spermatocytes divide more frequently than oocytes, so
increase chance of mutation (it’s not a Y chromosome mutation)
- Environmental impact on a genetic factor
Schizophrenia
• Clinical features
• Etiology (cause)– Genetic: – Environmental
• Neurobiology & Pharmacotherapy
Viral hypothesis (flu)
• Seasonal (previous slide)
• Urban
• Flu epidemic
Maternal influenza during fetal development (2nd trimester)
Stress hypothesis
• Flu is just a stressor
• Other stressors during 2nd trimester also increase risk:– Underweight mother– Underweight newborn– Famine (due to thiamine deficiency post-famine?)
– Your husband is killed– Increased cortisol
• stress video• may also explain disease onset in adolescence
Pre-morbid development
• Schizotypal personality disorder at adolescence– Social anxiety
– Affective abnormalities
– Eccentric behavior
– Unusual ideas (e.g., persistent belief in ESP)
– Unusual sensory experiences • (not strong enough to be delusions or hallucinations)
• Relation between SPD and schizo (20-40% of SPD -> schizo), familial link
Of those showing warning signs (prodromal phase)• 1/3 gets better as they enter adulthood • 1/3 continues to experience mild symptoms
• 1/3 develops schizophrenia or other psychosisThis latter group has the higher cortisol levels at prodrome
Cortisol levels increase with puberty (even in normal kids)
a disruptive family environment (stressor) is a risk factor.
Further evidence for cortisol hypothesis: in animal models, cortisol increase during pregnancy leads to abnormal hippocampus in the offspring
Schizophrenia
• Clinical features
• Etiology (cause)– Genetic: – Environmental
• Neurobiology & Pharmacotherapy
Positive symptoms: due to dopamine• Antipsychotic drugs (D2 blockers)
• DA agonists (e.g., cocaine)
20
Negative Symptoms: Frontal lobe lesion
… some lessons for life
• Flu Vaccine
• Reduce maternal stress (physical & psychological)
• Reduce teenager’s stress
• Raise concern about friend/relative when you deem doing so is warranted.
• Support early treatment (when onset is evident)
http://www.sfnsw.org.au/schizophrenia/symptoms.htm
http://www.emory.edu/EMORY_MAGAZINE/spring2000/inquiry.html
Summary
