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Abnormal Psychology Unit 5: Depressive and Bipolar Disorders

Mood disorders involve persistent, impairing disturbances of mood, from the low end (depression) to the high end (mania and hypomania). They are among the most common and treatable disorders, and understanding them is central to understanding suicide risk and prevention.

Covers: Major depressive disorder and its specifiers, Persistent depressive disorder and other depressive disorders, Bipolar I, bipolar II and cyclothymic disorder, Biological causes: genes, neurotransmitters and stress hormones, Cognitive, behavioral and interpersonal theories, Treatments: medication, psychotherapy, ECT and mood stabilizers, Suicide: risk factors, warning signs and prevention

Study guide

A major depressive episode requires at least five of nine symptoms nearly every day for at least two weeks, and at least one must be depressed mood or anhedonia, a loss of interest or pleasure. The other symptoms are significant weight or appetite change, insomnia or hypersomnia, psychomotor agitation or slowing, fatigue, feelings of worthlessness or excessive guilt, poor concentration or indecisiveness, and recurrent thoughts of death or suicide. Major depressive disorder (MDD) is diagnosed when episodes occur without any history of mania or hypomania. Specifiers describe features such as anxious distress, melancholic features, psychotic features, peripartum onset and seasonal pattern. MDD is about twice as common in women as in men after puberty. Bereavement does not rule out a diagnosis, but clinicians weigh whether symptoms reflect normal grief.

Persistent depressive disorder involves depressed mood most of the day, more days than not, for at least two years in adults (one year in children and adolescents), with at least two other symptoms such as poor appetite, low energy, low self-esteem or hopelessness. It is often milder than MDD but long-lasting, and the two can occur together. Premenstrual dysphoric disorder involves marked mood symptoms in the week before menstruation that improve after it begins. Disruptive mood dysregulation disorder, diagnosed between ages 6 and 18 with onset before 10, involves severe, frequent temper outbursts and a persistently irritable mood; it was added partly to reduce overdiagnosis of bipolar disorder in children. Bipolar disorders involve mania or hypomania. A manic episode is at least one week of abnormally elevated, expansive or irritable mood and increased energy, with symptoms such as grandiosity, decreased need for sleep, pressured speech, racing thoughts, distractibility and risky behavior.

Bipolar I disorder requires at least one manic episode; depressive episodes are common but not required. Mania causes marked impairment, may require hospitalization and can include psychotic features. Bipolar II disorder requires at least one hypomanic episode, lasting at least four days, and at least one major depressive episode, with no history of full mania. Hypomania is a noticeable change in functioning but is not severe enough to cause marked impairment or hospitalization. Cyclothymic disorder involves at least two years (one in youth) of many periods of hypomanic and depressive symptoms that never meet full episode criteria. A rapid-cycling specifier applies when a person has four or more mood episodes in a year. Bipolar disorders are among the most heritable mental disorders, with twin heritability estimates often between about 60% and 85%.

Biological explanations of depression include genetic risk, the monoamine hypothesis that low serotonin and norepinephrine activity contribute (now seen as too simple), HPA-axis overactivity with high cortisol, and reduced hippocampal volume. Psychological theories are just as important. Aaron Beck's cognitive theory describes negative schemas and the cognitive triad. Martin Seligman's learned helplessness theory began with dogs that stopped trying to escape shocks after uncontrollable shocks; the revised hopelessness theory of Lyn Abramson and colleagues says that attributing bad events to internal, stable and global causes predicts depression. Susan Nolen-Hoeksema showed that rumination, repetitive focus on distress, prolongs depression and may explain part of the gender gap. Peter Lewinsohn's behavioral theory points to low rates of positive reinforcement, and interpersonal theories stress loss, conflict and isolation.

Treatments for depression include antidepressants such as SSRIs, SNRIs, older tricyclics and MAO inhibitors, which require avoiding tyramine-rich foods. Cognitive therapy, behavioral activation and interpersonal psychotherapy are about as effective as medication for many people, and combined treatment helps those with severe depression. Electroconvulsive therapy (ECT), given under anesthesia, is highly effective for severe or treatment-resistant depression, and transcranial magnetic stimulation is another option. Bipolar disorder is treated with mood stabilizers such as lithium, which requires blood monitoring because of its narrow therapeutic range, and certain anticonvulsants and antipsychotics; antidepressants alone can trigger mania. Suicide is closely linked to mood disorders. Risk factors include prior attempts, hopelessness, substance use and isolation. Thomas Joiner's interpersonal theory stresses perceived burdensomeness and thwarted belongingness. Asking directly about suicide does not increase risk, and safety planning and crisis lines such as 988 in the United States save lives.

Key ideas

• Major depression requires five of nine symptoms for two weeks, including depressed mood or loss of interest.
• Persistent depressive disorder is chronic, lasting at least two years in adults.
• Bipolar I requires full mania; bipolar II requires hypomania plus major depression and no mania.
• Hopelessness theory predicts depression when people explain bad events with internal, stable and global attributions.
• Rumination and low positive reinforcement maintain depression, which is why behavioral activation helps.
• Lithium and other mood stabilizers are central to bipolar treatment, and antidepressants alone can trigger mania.
• Suicide risk rises with prior attempts and hopelessness; asking directly about suicide does not plant the idea.

Formulas and rules

Common mistakes

• Thinking bipolar II is a milder form of bipolar I; bipolar II involves major depressive episodes that can be severe and long-lasting.
• Requiring a depressive episode to diagnose bipolar I; one manic episode is enough.
• Mixing up the duration rules: two weeks for a depressive episode, one week for mania, four days for hypomania.
• Believing that asking someone about suicidal thoughts makes them more likely to act.
• Assuming the monoamine hypothesis fully explains depression; antidepressants raise serotonin within hours but take weeks to help.

Before the test, make sure you can

• List the nine symptoms of a major depressive episode and the two-week, five-symptom rule.
• Distinguish MDD, persistent depressive disorder, PMDD and disruptive mood dysregulation disorder.
• Compare manic and hypomanic episodes and diagnose bipolar I, bipolar II and cyclothymic disorder from a case.
• Explain biological theories of depression and their limits.
• Apply Beck's theory, hopelessness theory, rumination and behavioral theory to a case.
• Compare antidepressants, psychotherapies, ECT and mood stabilizers.
• Identify suicide risk factors and warning signs, and explain why direct questions and safety plans help.

Words to know

Anhedonia

A loss of interest or pleasure in activities that were once enjoyable.

Major depressive disorder

One or more major depressive episodes with no history of manic or hypomanic episodes.

Persistent depressive disorder

Chronic depressed mood for at least two years in adults, with at least two additional symptoms.

Psychomotor retardation

Visible slowing of movement and speech, a symptom of depression.

Peripartum onset

Specifier for mood episodes beginning during pregnancy or within four weeks after delivery.

Seasonal pattern

Specifier for mood episodes that regularly begin and end at certain times of year, often fall and winter.

Disruptive mood dysregulation disorder

Childhood disorder with severe recurrent temper outbursts and persistent irritability, diagnosed between 6 and 18.

Manic episode

At least a week of abnormally elevated, expansive or irritable mood and increased energy causing marked impairment.

Hypomanic episode

At least four days of elevated or irritable mood and increased energy that changes functioning but does not cause marked impairment.

Bipolar II disorder

At least one hypomanic episode and one major depressive episode, with no history of mania.

Cyclothymic disorder

At least two years of fluctuating hypomanic and depressive symptoms that never meet full episode criteria.

Rapid cycling

Specifier for bipolar disorder with four or more mood episodes in a year.

Learned helplessness

Seligman's finding that exposure to uncontrollable events leads to passivity and giving up.

Hopelessness theory

The view that internal, stable and global attributions for bad events produce hopelessness and depression.

Rumination

Repetitive, passive focus on one's distress and its causes, which prolongs depressed mood.

Behavioral activation

A therapy that schedules rewarding and meaningful activities to increase positive reinforcement.

Lithium

A mood stabilizer for bipolar disorder that requires blood monitoring due to a narrow therapeutic range.

Electroconvulsive therapy

A treatment for severe depression in which a brief seizure is induced under anesthesia.

Safety planning

A collaborative plan listing warning signs, coping steps, supportive contacts and crisis resources for a person at risk of suicide.

Sample practice questions

30 more questions like these, from level 1 to 5, are in the practice set.