Schizophrenia Flashcards
1
Q
Schizophrenia
A
- Distorted thinking, faulty perception and attention, lack of emotional expressiveness, disturbances in behavior etc.
- Substance use, suicide, men more, culture differences (African Americans), beings in adolescence.
2
Q
Positive symptoms: Delusions (6)
A
Belief contrary to reality:
- Thought insertion
- Thought broadcasting
- External force controlling their thinking/behavior
- Grandiose delusions: importance, power, knowledge, identity
- Ideas of reference
- Persecutory delusions: danger beliefs
3
Q
Positive symptoms: Hallucinations
A
- Sensory experiences in the absence of any stimulation from environment
- Auditory more than visual
- During: Broca’s area (frontal cortex: producing speech) and wernicke’s (temporal: understanding speech) are active. Therefore: miscommunication between the frontal lobe and temporal lobes.
4
Q
Negative symptoms (5)
A
- Endure beyond an acute episode.
- Many negative symptoms = poor quality of life
1. A-volition: lack of motivation.
2. A-sociality: impairments in social relationships.
3. Anhedonia: Loss of interest in please. Consummatory: experienced in the moment, anticipatory: pleasure from future events.
4. Blunted effect: lack of outward expression of emotions
5. Alogia: reduction in speech
5
Q
Disorganized speech
A
- Formal thought disorder: problems in organizing ideas and speaking coherently.
- Loose associations or derailment: successful in communication but difficulty sticking to one topic
6
Q
Disorganized behavior
A
- No ability to organize behaviors to conform to community standards.
- Catatonia: spectrum of unusual gestures or immobility or even waxy flexibility.
7
Q
Prevalence
A
- 1%
- Men more likely
- African Americans - bias
- Comorbidity - substance abuse
- Age: adolescents, not in children, later for women.
8
Q
Etiology: Behavioral genetics
A
- Family studies: relatives = high risk, more negative symptoms, gene + environment/experiences
- Twin studies: high risk
- Adoption studies
- Familial high-risk studies
9
Q
Etiology: molecular genetics research
A
- Not transmitted by a single gene - multiple genes
1. DRD2: encodes specific type of dopamine receptor (d2)
2. COMT: associated with cognitive control processes that rely on prefrontal cortex. Chromosome 22.
3. CNV deletions: 1% of genetic variance.
10
Q
Etiology: dopamine theory
A
- High dopamine levels = SP
- Related with positive and disorganized symptoms.
- Dopamine abnormalities in the prefrontal cortex accounts for negative symptoms - no strong evidence.
11
Q
Etiology: other neurotransmitters
A
- Blocking D2 and 5HT2 (serotonin and dopamine)
- Little serotonin = too much dopamine = SP
- Low levels of glutamate found in cerebrospinal fluid.
- High levels of amino acid homocysteine which interacts with NMDA receptor.
- PCP and ketamine induce positive and negative symptoms by interfering with NMDA receptors.
- Decreases NMDA and low glutamate levels lead to SP and disorganized symptoms.
12
Q
Etiology: brain structures and functions
A
- Enlarged ventricles
- Loss of brain cells.
- Correlated with impaired performance on neuro-psychological tests, poor functioning and poor response to medication. - Prefrontal cortex
- Plays a role for speech, decision making, emotion, goal-direction etc.
- MRI show reduction in gray matter and volume.
- Lower glucose metabolism
- Less activation related to severe negative symptoms
- Dendritic spines are lost (not neurons) = disrupted connections between neurons = speech and behavioral disorganization symptoms. Link with CNV genes. - Temporal cortex
- Temporal gyrus, hippocampus, insula, fusiform gyrus, amygdala and cingulate cortex.
- Reducting in cortical gray matter and volume
- HPA axis affected.
13
Q
Connectivity in the brain
A
- Less connectivity in brain white matter in the frontal/temporal cortices.
- Less connectivity in the brain networks, frontro-parietal and default mode networks = poor performance on cognitive tests.
14
Q
Etiology: environmental factors
A
- Damage during gestation or birth: reduced oxygen - loss of cortical gray matter.
- Maternal infections during pregnancy: toxoplasma gondii
- Cannabis: worsens symptoms + increase onset.
15
Q
Etiology: sociocultural factors
A
- High poverty = SP
- Living in urbanc areas = SP
- Migration = SP (3x for first generation, 4x for second generation)