Chapter 16: Psychopathlogy Flashcards
Psychiatric Disorders are…..
Highly prevalent in society
What fraction of the US will experience a psychiatric disorder at some point in their life?
1/3
What did 25% of patients in mental hospitals during the early 20th century suffer from?
Paralytic Dementia
Paralytic Dementia
Psychiatric disorder includes delusions, grandiosity, euphoria, and impulsiveness
What had caused paralytic dementia in the early 20th century?
Syphilis
What was paralytic dementia renamed to?
Syphilitic Psychosis
What did the case of paralytic dementia in the early 20th century prove about psychiatric disorders?
Psychiatric disorders have “organic” or biological orgins
What plays a large role in psychiatric disorders?
Genetics
How can disorders be organized?
In clusters based on genetics
What is the prevalence of scizophrenia?
Affects 1% of the population
When does schizophrenia usually emerge?
Adolescence / early adulthood
What are the 3 types of symptoms in schizoprhenia?
- Positive
- Negative
- Cognitive
What aspect in schizophrenia do positive symptoms relate to?
Psychosis (loss of reality)
What aspect in schizophrenia do negative symptoms relate to?
- Emotional dysregulation
- Impaired movement
What aspect in schizophrenia do cognitive symptoms relate to?
- Neuro cognitive impairment
Is schizophrenia heritable?
Yes but multiple genes must be involved
What has confirmed the importance of genetics in schizophrenia?
Adoption studies
What role do twin studies play in schizophrenia?
Genetics are not everything
What % do dizygotic twins have for obtaining the same trait related to schizophrenia?
17% rate
What % do monozygotic twins have for obtaining the same trait related to schizophrenia?
50% rate
What do studies of discordant twins indicate in schizophrenia?
A child who develops schizophrenia tends to be abnormal throughout their whole life.
What is a main feature of children who go on to develop schizophrenia?
Differences in eye tracking
Discordant Twins
Twins with a significant difference in weight or other characteristics
What individual genes are involved in schizophrenia cases?
- Neuregulin 1
- Dysbindin
- COMT
Neuregulin 1
- Schizophrenia
Regulates NMDA, GABA, and ACh receptors
Dysbindin
- Schizophrenia
Regulates synaptic plasticity
COMT
- Schizophrenia
Metabolizes Dopamine
What happens to many schizophrenics?
They end up homeless
What is schizophrenia considered?
A chronic and overwhelming disorder
What does “schizophrenia” mean?
“Split Mind”
What increases the chance of having a child with schizophrenia?
Older fathers having kids
What happens to the ventricles in schizophrenics?
They enlarge
Ventricular enlargement is a…
stable trait
What do patients with ventricular enlargement show a poorer response to?
Antipsychotics
What causes ventricular enlargement?
Buildup of cerebrospinal fluid in the brains ventricles
Gene DISC1 Protein
Regulates dendritic spines at glutamatergic synapses
Where is the Gene DISC1 Protein found?
In family with schizophrenia
What happens to mice that have a mutant DISC1 gene?
They obtain enlarged ventricles
What forms of limbic system abnormalities are found in schizophrenics?
- The walls of ventricles are smaller
- There is cellular disorganization (hippocampus and other limbic structures)
What do the walls of the ventricles make up in the brain?
The hippocampus and amygdala
What does cellular disorganization in the brain affect?
Pyramidal cells
What happens to the brain cortex in schizophrenics?
Thicker corpus callosum
What causes thicker corpus callosum in schizophrenics?
Abnormal neuronal migration in the frontal cortex.
What happens to gray matter during adolescence with schizophrenics?
There is a loss of cortical gray matter
What does evidence regarding the cortex suggest in schizophrenics?
Alterations in the frontal cortex results in impairments on tasks that depend on the frontal cortical area.
What did discovering a thicker cortex in schizophrenics lead to?
The Hypo Frontality Hypothesis
Hypo Frontality Hypothesis
Insufficient activity of the frontal cortex
What role to antipsychotics play in the hypo frontality hypothesis?
They increase activation of the frontal cortex
Amphetamines
Stimulant drugs (BAD) that can produce psychosis
- Found in schizophrenia
What can block amphetamines?
Chlorpromazine
Chlorpromazine
A dopamine antagonist used against amhetamines
What were the 1st antipsychotics?
Chlorpromazine and its relatives
What do typical antipsychotics block?
D2 (dopamine) receptors
What is the recommended dose of antispychotics to treat schizophrenia correlated with?
The dopamine D2 receptor binding affinity of the specific drug.
Drugs with a higher binding affinity for D2 receptors….
can treat schizophrenia with lower doses
What is the relationship between Parkinson’s and Schizophrenia?
L Dopa (Parkinson’s treatment) can produce schizophrenia like symptoms.
What are the 2 Neurotransmitter Hypothesis for schizophrenia?
- Dopamine Hypothesis
- Glutamate Hypothesis
Dopamine Hypothesis
Schizophrenia results from either…
- excessive level of synaptic dopamine
or
-excessive postsynaptic sensitivity to dopamine
What are the 4 problems with the Dopamine Hypothesis?
- There are no consistent results that look at dopamine metabolization.
- The DA blockers take too long to affect schizophrenia (compared to their normal speed).
- Some people with schizophrenia are not helped by typical antipsychotics (dopamine based).
- The atypical antipsychotics have less affinity for DA receptors.
Glutamate Hypothesis
Schizophrenia is caused by under stimulation of glutamate receptors.
What drug plays a major role in the glutamate hypothesis?
Phencyclidine (PCP)
How does Phencyclidine (PCP) induce schizophrenia?
PCP blocks gutamatergic actions, resulting in psychosis sympptoms
What type of effect is PCP?
Non competitive NMDA receptor antagonist
What happens when PCP binds to a receptor?
No other ligand can bind and activate the NMDA receptor?
= No glutamate production
What does Schizophrenia most likely develop from?
The interaction between genetics, development, and environment.
How does your location of living relate to Schizophrenia?
Living in a city increases your risk for Schizophrenia
- Increased stress levels
What are the 4 risk factors of Schizophrenia?
- City vs Rural living
- Having the flu during 1st trimester
- Birth complications/lack of oxygen
- Incompatible blood types
What is the gender ratio of mood disorders?
Women are 2x more affected than men
When do the highest rates of mood disorders occur?
Around age 40
What is the twin coordinance for mood disorders?
Monozygotic: 60%
Dizygotic: 20%
What is the most common mood disorder?
Depression
What are the chacaterictics of depression?
- Unhappy mood
-Loss of interest - Difficulty in concentration
- Restless agitation
Unipolar Depression
Depression that alternates with normal emotional states