mental illness. schizophrenia features of schizophrenia (positive symptoms) positive symptoms...

Mental Illness

Schizophrenia

Features of Schizophrenia (Positive Symptoms)

• Positive symptoms– Psychosis

• Hallucinations– Auditory– Visual– Olfactory, somatic

• Delusions– Grandeur– Persecution

Features of Schizophrenia

• Positive symptoms (continued)– Disorganized thought

• Speech• Neologism• Word salad

Features of Schizophrenia

• Positive symptoms (continued)– Disorganized behavior

• Poor grooming• Meals• Inappropriate clothing

Features of Schizophrenia (Negative Symptoms)

• Negative symptoms– Withdrawal– Flat affect (no facial expressions)– Talk little– Lack of motivation

Possible associations

• Blame the mother!

• Prenatal infection

• Genetics

• Brain structure

• Dopamine theory

1. Of course it’s that crappy mother’s fault!

• “Refrigerator mother”

• Notes

2. Viral Infection

• Mom caught the flu during second trimester of pregnancy (months 4-6)

• Also, people with schizophrenia more likely to be born during winter-spring mom was in second trimester during peak of flu season

3. Genetics

• 1% of general population

• Risk of developing schizophrenia appears to be associated with how closely you are related to a person with schizophrenia

• Stress-diathesis model

Figure 15.18 Family relationships and the risk of developing schizophrenia Klein/Thorne: Biological Psychology© 2007 by Worth Publishers

4. Brain Structure

Figure 15.15 MRI scans of the brains of twins discordant for schizophrenia Klein/Thorne: Biological Psychology© 2007 by Worth Publishers

4. Brain Structure

• Larger ventricles

• Decreased activity in prefrontal cortex– Hypofrontality (negative symptoms)

5. Dopamine Hypothesis

• Excessive dopamine activity associated with positive symptoms of schizophrenia

• Drugs that decrease symptoms– Dopamine antagonists

• Drugs that cause schizophrenia-like experiences– Increase activity of dopamine in brain– Amphetamine and cocaine

5. Dopamine Hypothesis

• One of the first medications for schizophrenia– Chlorpromazine– This is an antagonist of dopamine: prevents

dopamine from binding to receptors

– Tardive dyskinesia

Figure 15.12 The synaptic effect of chlorpromazine Klein/Thorne: Biological Psychology© 2007 by Worth Publishers

Mood Disorders

Depression

Depression

• For 2 weeks or more, almost every day• Feelings of sadness• Things are not interesting or fun anymore• Changes in appetite and weight• Problems with sleep• Lethargic/fidgety• Lack of energy• Problems with thinking and concentration• Thoughts of death and suicide

Associated with …

• Life events

• Genetics

• Hormones

• Brain abnormalities

1. Life events

• Too much bad stuff or too little good stuff?

• Learned helplessness

2. Genetics

• Concordance rate for monozygotic (identical) twins: 48%

• Dizygotic twins: 23%

• Adoption studies: account for flaws in other genetic studies

3. Hormones

• Embedded in broader social context:– Post-partum depression– Pre-menstrual dysphoric disorder (PMDD)

4. Hypercortisolism

• Cortisol – stress hormone– Secreted by the adrenal cortex

• Dexamethasone suppression test (DST)– Synthetic hormone that suppresses cortisol in

non-depressed people

How to treat depression

1) Psychotherapy (won’t have time to discuss)

2) Medication

3) Electroconvulsive therapy

2. Medications

• Tricyclics (TCA)– Prevent reuptake of norepinephrine and

serotonin

• Monoamine oxidase inhibitors (MAOI)– Prevent degradation of norepinephrine and

serotonin

• Selective serotonin reuptake inhibitors (SSRI)

Figure 15.5 The synaptic effects of three types of antidepressant drugs Klein/Thorne: Biological Psychology© 2007 by Worth Publishers

2. Medications – Safety

• TCA– Can be dangerous for people with heart

problems

• MAOI– Dangerous if eat food high in tyramine

(cheese, wine, pickles); causes dangerous increase in blood pressure

• SSRI– Fewer and less dangerous side effects

3. Electroconvulsive Therapy (ECT)• Who is it used for?

• How is it done?

• How does it work?

• What are the side effects?

Figure 15.6 Use of electroconvulsive therapy (ECT) to treat major depression Klein/Thorne: Biological Psychology© 2007 by Worth Publishers

Obsessive-Compulsive Disorder

OCD

• Obsession– Thoughts, ideas, images

• Contamination• Something bad happening

• Compulsion– Repetitive behaviors to reduce anxiety caused

by obsession• Clean• Check• Count

OCD

• Time consuming

• Distress, impairment

• Awareness that obsessions and compulsions are excessive

• Stressful trigger

• Genetic component?– Runs in families

• Brain injury or infection– Basal ganglia, frontal lobe, thalamus– Unable to “shut off”

OCD treatments

• Exposure and response prevention

• SSRI

• Surgery: sever connections between frontal lobe and caudate nucleus (in basal ganglia)

Is there such as thing as mental illness?