Chapter Fifteen Flashcards
Schizophrenia affects…
1% of the population
When do symptoms of schizophrenia emerge?
between late teens and mid-thirties
What is the mortality rate of those with schizophrenia?
10% due to suicide
Positive symptoms
made known by its presence; non-schizos will NOT do this
Negative symptoms
made known by its absence; non-schizos WILL do this
Biological determinants of Schizophrenia
heredity; studies of adoption ruled out environment; MZ twins run a 50% concordance rate; likely that children inherit a vulnerability that is brought out by something environmental
Dopamine/Pharmacology of Schizophrenia
over-accumulation of dopamine in the brain; DA antagonists reduce positive symptoms, while agonists make them worse;
What drug products Schizophrenia symptoms?
cocaine
Too much dopamine?
too much released, receptors might be overly sensitive to DA, slow reuptake keeps DA in synapse
Laruelle et al. (1996)
when given amphetamines, schizos released more DA than controls
Other studies done on Schizo’s show..
increased number of DA receptors in brains of schizo patients
What appears to account for positive symptoms?
increased DA
Weinberger & Wyatt (1982)
ventricles getting larger ; other studies show the cortex is getting smaller, which is normal process of aging, but accelerated in schizos
Epidemiological Research
studies of diseases among a population-looks at trends in occurrences
Seasonal Effects of Schizo
more born between Feb and May; numbers increased if previous fall was especially cold; could be a virus/bacteria picked up in fall/early winter that “plants the seed” for manifestation later on; higher rates in cities; higher rates in babies born after flu epidemic; higher rates in women who experience extreme stress during pregnancy;
NOT cause and effect; but points to environmental trigger for the disease
Monochorionic (MC)
fed by 1 placenta; share amniotic sac; same prenatal environment; 60% concordance rate with Schizo
Dichoriotic (DC)
fed by 2 placenta; 2 amniotic sacs; 11% concordance rate with Schizo
If split happens after day 4—>
MC
If split happens prior to day 4–>
DC
Unipolar
major depression
bipolar
mania and depression
what percent of those with unipolar attempt suicide?
15-30%
Biological Substrates of Affective Disorders
run in families; if close family member suffers, others 10x as likely, 69% concordance rate among identical twins, 13% concordance rate among fraternal twins
Bipolar
lithium salts work 70-80% of patients; curbs manic symptoms, no lasting side effects
What do schizo patients report feeling before an episode?
euphoria/elation before an episode which might be the same system involved in rewarding drug effects
Unipolar depression treatments
increase NE and SE levels in the brain
MAO inhibitors
work but have side effects
Tricyclic antidepressants
early meds that work
SSRI
specific serotonin reuptake inhibitors- prozac is well known
How long to antidepressants typically take to work?
2-4 weeks
Electroconvulsive Therapy (ECT)
physicians noticed improvement in symptoms after patients had seizures
What are the steps to ECT?
anesthesia, muscle relaxers, current applied to right hemisphere
How many treatments do ECT patients get?
3x/week for 2-4 weeks
What is the side effect of ECT?
memory loss
Monoamines
depression is accociated with insufficient monoamines, especially NE and SE
What do monoamine antagonists do?
cause depression- reserpine is used to blood pressure but has a side effect of depression
What is related to monoamine depletion?
suicidal tendencies
Brain imaging studies
found difference in activity in the amygdala & prefrontal cortex, but no differences in structure
What type of sleep do depressed people show?
shallow sleep; more stage 1, less stage 3/4
REM sleep deprivation and depression
effective treatment; takes a few weeks to be effective, just like antidepressants
Scherschilicht et al. (1982)
looked at common meds for treating depression and all of them affected REM sleep patterns
Total sleep deprivation and depression
produces immediate relief of depressions
Wu and Bunny (1990)
showed that responders benefit the most from total sleep deprivation
responders
those who feel more depressed in the morning but get in a better mood as the day progresses
Seasonal affective disorder (SAD)
depression caused by changes in seasons…specifically in sunlight exposure
what does light exposure regulate?
melatonin released by pineal
What do SAD patients often crave?
carbohydrates; will show weight gain during episodes
what is the most effective treatment for SAD?
phototherapy
Anxiety Disorder physiological symptoms
rapid breathing, sweating, dry mouth, increased heart rate
Anxiety Disorder psychological symptoms
feeling of dread; fear
Panic Disorder
unpredictable bouts of high anxiety
Who does anxiety disorder effect?
1-2% of population; early onset equal among males and females
causes of anxiety disorders
runs in families; higher rates for MZ twins
How are anxiety disorders triggered?
arousal of autonomic nervous system; caffeine, amphetamines
How are anxiety disorders treated?
medications and behavioral therapy
OCD
upsetting thoughts (O) and repetitive behaviors (C)
who does OCD effect?
1-2%; females slightly more
what are different examples of those with OCD?
counters, checkers, cleaners
Treatment of OCD
medications show promise, but its a hard disorder to treat
causes of OCD
linked to tourettes syndrome, birth trauma, encephalitis, head trauma
What are the brain differences in those with OCD?
differences in the basal ganglia and prefrontal cortex; increased activity in frontal lobes and caudate nucleus
