PSYCHOPATHOLOGY PART 1

psychiatric disorder

AKA mental illness and psychological disorders

behavior and/or mental patterns that cause significant distress or impairment of personal functioning

diagnosed on the basis of behavioral symptoms: ICD and DSM

epidemiology

studies patterns of disease in a population

one-third

about ______ of the US population reports symptoms

schizophrenia

characterized by disordered thoughts

serious psychiatric disorder in which people interpret reality abnormally

affects about one percent of the population

symptoms typically begin typically begin in late adolescence or early adulthood

John Nash

mathematician that developed symptoms of schizophrenia in his 30’s

won the nobel prize in 1994

recovered from disease late in his life (sometimes happens for unexplained reason)

positive schizophrenia

positive = presence of unusual behaviors, in excess of typical functioning

• thought disorders

• delusions

• hallucinations

• bizarre motor behavior

dissociative thinking

impaired logical thought

delusions

beliefs in obvious contrast to fact

EX: persecution

hallucinations

perceptions of stimuli that are not present

EX: most are auditory

negative scizophrenia

emotional dysregulation: lack of emotional response (flat affect)

anhedonia

impaired motivation: poverty of speech (alogia), social withdrawal, lack of initiative / persistence

anhedonia

inability to experience pleasure

cognitive schizophrenia

difficulty sustaining attention

low psychomotor speed: ability to detect and respond to rapid changes in the environment

deficits in learning and memory

poor abstract thinking

poor problem solving

heritable

schizophrenia is partly ______, but many genes play a role

monozygotic

identical twins share identical genes

dizygotic

fraternal twins have half of their genes in common

concordant

if both twins suffer from schizophrenia

discordant

only one member of twins experiences the disease

stuctural changes

brains of many schoziphrenic patients show consistent _____

cerebral ventricles are enlarged, especially lateral ventricles

disrupted in schizophrenia 1 (DISC1)

mutation in mice leads to enlarged lateral ventricles

this gene regulates embryonic and adult neurogeneiss

mutation in some families have high incidence of schizophrenia

hippocampus and amygdala

smaller than typical in schizophrenics

pyramidal cells of the _____ have a disorganized arrangement

integration of _____ cells (neuroeneis) may be disordered

hypofrontality hypothesis

schizophrenia may be caused by underactivation of the frontal lobes

studies show a loss of gray matter int he frontal lobes in adolescents

PET shows reduced metabolic activity in the frontal lobes

older

_______ fathers are more likely to have a child with schizophrenia

Increased likelihood of mutations in chromosomes of cells that produce sperm (chance of mutations increases with number of times cells have divided)

dopamine hypothesis

schizophrenia results from excess synaptic dopamine or dopamine receptors

support comes from amphetamine abusers who develop positive symptoms (amphetamine psychosis)

amphetamine promotes release of dopamine and blocks its reuptake

antipsychotic

drugs work by blocking dopamine D2 receptors

blocks the effects of dopamine agonists which produce positive symptoms

dopamine pathways

mediate negative and positive symptoms

include mesolimbic and mesocortical

mesolimbic pathway

overactive, primarily postive symptoms

mesocortical pathway

underactive, primarily negative symptoms

atypical antipsychotics

partial agonists of dopamine receptors, bind to dopamine receptors, BUT don’t activate it as much as dopamine or typical antipsychotics

acts as a partial agonist here there is too little dopamine and as a partial antagonist where there is too much dopamine

dyskinesia

distortion in voluntary movement

long term efects of antipsychotic drugs

tardive dyskinesia

repetitive movements involving the face, mouth, lips, and tongue (irreversible unknown mechanism)

environmental factors of schizophrenia

• season of birth

• viral epidemics

• vitamin D defficiency

• population density

• prenatal manutrition and stress

• substance abuse

stress

a common underlying environmental factor of schizophrenia

transition from childhood to adulthood

pollutants, greater exposure to diseases, crowds, tense social interactions, etc.

stress of city living

may contribute to schizophrenia

increased amygdala activity

urban areas get more sun exposure, individuals with darker skin / more vitamin D show less schizophrenia

prenatal malnutrition and stress and schizophrenia

German woman pregnant during WWII and the famine of China had more schizophrenic children

syphilis

an infection caused by bacteria often spread through sexual contact

used to be fatal up until the creation of penecillin

paralytic dementia

shared many characteristics with schizophrenia (delusions, odd behavior, etc.)

brain damage by syphilis was found responsible

affective mood disorders

characterized by disordered feelings / moods

risk of suicide is increased

bipolar disorder

has more in common with schizophrenia than with major depressive disorder (enlarged ventricles and more likely to have a family member with schizophrenia)

2x as much risk of suicide than depression

periods of depression alternating with expanisve mood (mania)

brain imaging shows more activity during manic bouts

susceptibility

men and woman are affected equally by bipolar disorder

artistic / creative people are more likely to have bipolar disorder and schizophrenia

6%

of 500 people prevented from committing suicide on the golden gate bridge only _____ later committed suicide

depression

AKA unipolar depression, the most prevalent mood disorder

characterized by unhappy mood, loss of interest, low energy and appetite, difficulty concentrating, restless agitation

can occur with no readily apparent stress and can last for months if untreated

hereditary links

depression has strong ______

concordance rate is higher with identical twins than with fraternal twins

many genes contribute: genes coding for dopamine D2 receptor (pleasure signaling) and serotonin transporter may be involved

PET scans for depression

show increased blood flow in the prefrontal cortex and amygdala

decreased blood flow to the parietal and posterior temporal cortex and anterior cingulate (both involved in attention)

monoamine hypothesis

insufficient activity of monoamines at synapses causes depression

monoamine agonist REDUCE symptoms of depression and monoamine antagonist PRODUCE depression

dopamine agonists DO NOT treat depression so focus has been on serotonin (5-HT) and norepinephrine (NE)

euphoria

dopamine agonists cause ______

reserpine

reduces high blood pressure; reduces norepinephrine and seratonin release in the brain and can cause profound depression

sometimes used in dart gun to tranquilize animals and reduce psychotic episodes in humans

monoamine hypothesis problems

too simple and can’t explain all cases

does not account for therapeutic lag: NT in synapse increases rapidly, antidepressent effect takes weeks

suggests that something other than just monomines underlies therapeutic effects of antidepressants

cushing’s syndrome

people with abnormally high levels of circulating adrenal glucocorticoids (cortisol) are prone to depression

suggests that dysfuction of the hypothalamic pituitary- adrenal (HPA) axis may be involved in depression

People who attempt suicide also often have high levels of circulating cortisol

postpartum depressionn

suggests that some combination of hormones can precipitate depression

reproductive hormones

_____ _______ may be involved in depression

seen in depression through female reproductive cycles, birth control pills, and menopause

season affective disorder

symptoms of depression start out in the fall or winter, continue through winter, and then resolve in spring or summer

can be treated with phototherapy

EX: many sunny states have lower levels of depression

zeitbergers in depression

lack of stage 3 sleep in depression, REM latency reduced

SSRIs

selective serotonin reuptake inhibitors (EX: prozac)

acts on monoamine system

SELECTIVE because they mostly affect serotonin not other neurotransmitters

typically have fewer side effects than other types antidepressants

SNRIs

serotonin norepinephrine reuptake inhibitors

may not be significantly better than SSRIs (has the same therapeutic lag as SSRIs, both take weeks to produce antidepressant effects)

monoamine oxidase inhibitors

an enzyme that inactivates all the monoamines: norepinephrine, dopamine, and serotonin

requires a restricted diet that excludes tyramine found in aged cheese and smoked meat to prevent blood pressure spikes

used when newer drugs are not working

severe depression

SSRIs appear to be more effective in people with ____ _____ than those with mild depression

ketamine

a glutamate receptor antagonist that can cause sedation, pain relief, and trance-like state; can bring immediate relief of depression symptoms BUT the long term effects are unknown

antidepressant mechanism is unknown

non-pharmacological treatments for depression

• cognitive behavioral therapy (CBT)

• electroconclusive therapy (ECT)

• vagus nerve stimulation

• transcranial magnetic stimulation (TMS)

• deep brain stimulation (DBS)

• sleep deprivation

electroconclusive therapy (ECT)

brief electrical shock used to induce seizure

rapid effects, but usually used only in treatment - resistant cases

may stimulate release of monoamines and may REDUCE effects of an over-active prefrontal cortex

antidepressants

________ can trigger manic episodes in individuals with bipolar disorder

antipsychotics

________ much less effective in bipolar disorder than in schizophrenia

lithium

used to treat bipolar disorder, mechanism is unknown BUT it interacts with the circadian clock and boosts BDNF activity

rapid effects but low therapeutic index