Pysch disorders pt. 2

Generalized anxiety disorder (GAD)

persistent, excessive anxiety and worry

• most common in 18-29 yo, decreases with age

DSM-5 criteria for GAD

excessive anxiety and worry occurring more days than not for at least 6 months (about several events or activities)

• Understand irrationality of consistent anxiety/worry

Generalized anxiety disorder (GAD) 3+

• Restlessness, feeling on edge

• Fatigue

• Concentration problems

• Irritability

• Muscle tension

• Sleep disturbance

Biological and environmental factors

Imbalance of neurotransmitters, but precise nature of imbalance is not clear

Especially prevalent among people who:

• have low income

• live in large cities and/or environments that are unpredictable based on political and economic issues

• trauma in childhood can increase risk of developing GAD

Drug treatment - Benzodiazepines

• anxiolytic drugs

• Bind to GABA receptors and enhance GABA’s inhibitory actions

GABA_A receptors

• GABA_A receptors - widely distributed in the brain

• Cortex, hippocampus, and amygdala

• SSRIs can also treat anxiety

Mood disorders

long-lasting emotional disturbance that affects all areas of life

• Depressive and bipolar disorders

Major depressive disorder (MDD; unipolar depression)

severely depressed mood that lasts 2 weeks or more

MDD symptoms

• Feelings of worthlessness

• Loss of interest in enjoyable activities and personal appearance

• Changes in appetite (weight gain or loss)

• Sleep disturbances

• Increased substance use

• Cognitive issues (memory, EF, decision-making)

MDD stats

• 18% of people in US meet criteria for depression at some point in their lives

• Major depression lasts ~12 weeks, on average

• Without treatment, 80% of people will experience at least 1 recurrence

Gender imbalance of depression

• Women (22%) experience depression at a higher rate than men (14%)

• Lower SES, sex differences in hormones, postpartum depression, maybe women are more likely to seek help & receive diagnosis

Biological factors of MDD

• Depression may involve depletion of norepinephrine and serotonin

• Some newer studies found increases linked to depression

• Biochemical model of depression incomplete

MDD drug treatment

• drugs that affect norepinephrine, dopamine, and serotonin

• Modern antidepressants

• SSRI’s = selective serotonin reuptake inhibitors

• Can also treat anxiety

SNRI’s = serotonin-norepinephrine reuptake inhibitors

Issues with drug treatments

Problems with idea that reduced serotonin causes depression:

• Long lag-time (often weeks) between treatment and reduction of symptoms

• Not everyone responds to SSRIs

• Some SSRI benefits are attributable to placebo effect

Genes

• Moderate heritability, increases as function of severity

• Diathesis–stress model; influence of major stressful life events

• Internal predisposition + external stress

Diathesis-stress model

person may be predisposed to a mental disorder that remains unexpressed until triggered by stress

Serotonin transporter gene

5-HTTLPR

Short allele

linked to increased risk of depression (one or two copies)

Long allele

Better serotonin regulation

Environmental factor

major life stress

Allele impact

Short alleles + more stressful life events cause more major depressive episodes.

More long alleles + more stressful life events are stable.

Aaron Beck (1967)

Noted dysfunctional attitudes and negative mood states in people who were depressed - developed a cognitive model of depression

Helplessness theory

people prone to depression automatically attribute negative experiences to causes that are internal, stable, and global.

Negative thought pattern

Student at risk for depression

1. Receives poor grade on exam

2. Views grade as sign of low intelligence (internal)

3. Will never change (stable)

4. Will lead to failure on all future endeavors (global)

Negative cognitions

“I am no good at anything”

Negative emotions

Experiencing sadness or depression

Negative behaviors toward others

Such as being gloomy and having no fun

Negative responses from others

Such as being avoided by them