Chapter 16 Depression

Two Major Categories of Mood Disorder Major depressive disorder (unipolar): Lengthy, uninterrupted periods of depressed mood. Manic depressive disorder (bipolar): Cycling between periods of elevated mood (mania) and depression. While sharing the common feature of depression, these are unique and separate disorders.

Major Depressive Disorder Symptoms Depressed mood most of the time Lack of energy or restlessness Loss of pleasure in normally fun activities Feelings of hopelessness, worthlessness Sleep disturbances Eating disturbances Difficulty concentrating Suicidal thoughts

Major Depressive Disorder is the “Common Cold” of Mental Disorders As many as 12% of men and 21% of women may experience major depressive disorder during their lifetimes. Most patients with MDD are women. –Prior to adolescence, boys and girls are equally likely to experience depression. –In adults, about 2/3 of patients with depression are female. Most patients experience 5– 6 episodes during their lifetimes.

Age of onset of major depression

Bipolar Disorder Periods of mania alternate with depression. Mania is characterized by: –Inflated self-esteem (grandiosity) –Reduced need for sleep –Talkativeness –Racing thoughts –Distractibility –Goal-oriented behavior –Excessive involvement in pleasurable activities

Prevalence of Bipolar Disorder Affects 0.4–1.2% of the population Males and females are equally likely to be diagnosed with bipolar disorder. Rare prior to puberty; approaches adult prevalence in adolescence May be more prevalent among artistic and creative people

Mood Disorders and Creativity

Risk Factors Concordance rate for mood disorders among identical and fraternal twins

Risk Factors Stress: The HPA Axis

Risk Factors Stress: Abnormalities in glucocorticoids

Depressed people: enter REM earlier. spend little time in Stage 3 or 4. awaken frequently. Risk Factors Sleep Patterns

Antidepressants Monoamine oxidase inhibitors (nardil) Classic tricyclics (elavil) Selective reuptake inhibitors (prozac, zoloft, paxil) Atypical antidepressants (wellbutrin)

Therapies for Affective Disorders Acute and long-term effects of MAO-Is on synaptic function Acute effects Chronic effects Normal

Therapies for Affective Disorders Tricyclic antidepressants

Therapies for Affective Disorders Selective serotonin reuptake inhibitors (SSRIs)

Copyright © 2004 Allyn and Bacon Electroconvulsive therapy (ECT): A brief electrical shock, applied to the head, that results in an electrical seizure; used therapeutically to alleviate severe depression.

Therapies for Bipolar Disorders Lithium

Theories on Affective Disorders monoamine hypothesis

Theories on Affective Disorders glucocorticoid hypothesis

Neurochemical Bases of Mood Disorders Effect of stress and antidepressant treatment on BDNF in hippocampal cells