Final: Schizophrenia Flashcards
characteristics of schizophrenia
split mind
major disturbances in thought, emotion, movement, behavior
disordered thinking: ideas not logically related, faulty perception and attention
- perceptual distortions include hallucinations
lack of emotional expressiveness
- inappropriate or flat emotions
prevalence of schizophrenia
1% - 2.6 million adults in US
- one of top 15 leading causes of disability
affects MEN more than women
age onset: late adolescence, early adulthood (men diagnoses at earlier age than women)
what are some environmental risk factors
growining up in large cities
-air pollution - toxins
stress of the hustle and bustle
can lead to an immune rxn
what % of patients attempt suicide
20-50% (10% are successful)
association between immune dysfunction and schizophrenia
-birth season is a risk factor (late winter, early spring at inc risk, usually inc risk of getting sick then too)
-they are prone to infections
-autoimmune disorders inc risk
-proinflammatory cytokines inc and anti inflammatory cytokines reduced
antipsychotics restore levels
perinatal complicatons associated with inc scz rates in offspring
inc maternal cytokines or exposure to viral infection in 2nd trimester - inc risk of Scz in offspring
malnutrition
fetal brain injury in pregnancy/delivery caused by oxygen deprivation or drug use
behaviors in early infancy signal a potential risk
passive and apathy - no longer interested in new things
reduced responsiveness to verbal commands
difficult temperament (how well they respond to chanegs in environment)
poor sensorimotor performance
genetic contribution
varies according to hw many genes one shares with someone that has the disorder
- monozygotic twins only 50% the other will get it
multiple genes at different loci are effected
disruption of communication btw ionotropic and metabotroic families of receptors
ex: polymorphisms in DISC1gene assoiated with cognitive sypmtoms and pproper neural development
genetic vulnerability inc probability that the events during perinatal brain development will contribute to the occurence of Scz
2 hit model of Scz development - first hit
genetic vulnerability inc the probability that events during perinatal brain development will contribute to the occurrence of Scz
2 hit model of Scz - second hit
in adolescence neurodevelopmental errors and environmental events produce the diagnosable symptoms
stressors put someone over edge to develop symptoms
diagnosis
difficult
no 2 individuals show sam pattern of symptoms - no single symptom occurs in every patient
symtoms inc and dec over time
type of symptoms also change over time
symptoms often seen in other disorders
3 major clusters of symptoms
positive
negative
cognitive
positive symptoms
delusions
hallucinations
adding behavior
negative symptoms
avolition alogia anhedonia blunted affect asociality
cognitive/disorganized symptoms
disorganized behavior
disorganized speehc
delusions
+ symptoms
firmly held beliefs
contrary to reality
resistant to disconfirming evidence
types of delusions
persecutory (the CIA [lanted a listening device in my head, 65% have these)
thought insertion thought broadcasting outside control grandiose delusions ideas of reference
hallucinations
+ symptom
sensory experiences in absence of sensory stimulation
types of hallucinations (3)
auditory (74% have)
visual
hearing voices (inc activity in Brocas area in hallucinations)
lack of interest, apathy, difficulty initiating/persisting in goal-directed behavior
avolition
social withdrawal
inability to form close personal relationships
asociality
inability to experience pleasure
anhedonia
exhibits little or no emotion in face or voice
blunted/flat affect
peculiar, rigid posture, inappropriate gestures, overt signs of tension, repetitive movement
motor disturbances
reduction in speech
alogia
cognitive symptoms
impaired working memory, executive functioning, attention
disorganized speech (incoherence - inability to organize ideas) -loose associations (hard to stick to one topic)
disorganized behavior - silliness, agitation, unusul dress
DSM-5 criteria for Scz
2 or more must be present for at least one month
hallucinations, delusions, disorganized speech, disorganized behavior, neg symptoms
what brain region with positive symptoms
mesolimbic
what brain region with affective symptoms
ventromedial PFC
what brain region with aggressive symptoms
loss of orbitofrontal cortex
overactivity of amygdala
what brain region with cognitive symptoms
dorsoloateral PFC
what brain region with negative symptoms
mesocortical and Nacc
structural abnormalities in Scz brain
atrophy of cerebral cortex
enlargement of ventricles
what is the reduced brain volume due to
smaller neuronal cell bodies, reduced dendritic density, close packing of cells
poor connectivity btw brain regions
where are cells dsorganized - what brain region
hippocampus
loss of cortical ____
gray matter
impaired integration for sensory and cognition
dec structural connectivity in white matter tracts btw frontal, temporal, parietal lobes
hypofrontality hypothesis
dec activity in frontal lobe in Scz
Scz need to work hardr to get same executive control as healthy people
what are the neurotransmitter systems involved in Scz
dopamine, glutamate, serotonin
dopamine hypothesis
excess DA function results in + symptoms of Scz
hyperactivity at D2 receptors: dtrong correlation btw D2 receptor blockade and dec in Scz symptoms (inc in impulsivity, cognitive symptoms, agitation)
what can produce psychotic reactions in healthy individuals reversable by DA antagonists
amphetamine
DA imbalance hypothesis
neg symptoms and impaired thinking due to dec DA in mesocortical regions!
excess DA function in mesolimbic leads to + symptoms
hypoglutamate model
dec glutamate activity in Scz
blocking NMDA recetors with PCP or ketamine produces psychosis similar to psychosis in Scz
glutamate - DA interaction
insufficient NMDA, Glu can explain the inc in mesolimbic DA and dec in PFC activity
hyperactivity/ imbalance of serotonin at what receptor can result in psychosis
5-HT2A
- always excitatory - depending on location can stimulate or inhibit glu release
