Week 3 Treating Depression

Chapter 7

Depressive and Bipolar Disorders

How Common Is Unipolar Depression?

• Around 9% of adults in the U.S. suffer from severe unipolar depression in any given year – As many as 5% suffer from mild forms

• Around 19% of all adults experience unipolar depression at some time in their lives

• The prevalence is similar in Canada, England, France, and many other countries

• The rate of depression is higher among poor people than wealthier people

What Are the Symptoms of Unipolar Depression?

• Five main areas of functioning may be affected:

Emotional symptoms

• Feeling “miserable,” “empty,” “humiliated”

• Experiencing little pleasure

Motivational symptoms

• Lacking drive, initiative, spontaneity

• Between 6% and 15% of those with severe depression die by suicide

Behavioral symptoms

• Less active, less productive

Cognitive symptoms

• Hold negative views of themselves

• Blame themselves for unfortunate events

• Pessimistic

Physical symptoms

• Headaches, dizzy spells, general pain

Symptoms may vary from person to person

Diagnosing Unipolar Depression • Criteria 1: Major

depressive episode – Marked by five or

more symptoms lasting two or more weeks

• In extreme cases, symptoms are psychotic, including

– Hallucinations – Delusions

• Criteria 2: No history of mania

Diagnosing Unipolar Depression

• Two diagnoses to consider: – Major depressive disorder

• Criteria 1 and 2 are met – Dysthymic disorder

• Symptoms are “mild but chronic” – Depression is longer lasting but less disabling – Consistent symptoms for at least two years

– When dysthymic disorder leads to major depressive disorder, the sequence is called “double depression”

What Causes Unipolar Depression?

• Stress may be a trigger for depression – People with depression experience a greater

number of stressful life events during the month just before the onset of their symptoms

– Some clinicians distinguish reactive (exogenous) depression from endogenous depression, which seems to be a response to internal factors

What Causes Unipolar Depression? The Biological View

Genetic factors • Family pedigree, twin, adoption, and

molecular biology gene studies suggest that some people inherit a biological predisposition • Researchers have found that as many as

20% of relatives of those with depression are themselves depressed, compared with fewer than 10% of the general population

What Causes Unipolar Depression? The Biological View

Genetic factors • Twin studies demonstrate a strong genetic

component: • Concordance rates for identical (MZ) twins = 46% • Concordance rates for fraternal (DZ) twins = 20%

• Adoption studies also have implicated a genetic factor in cases of severe unipolar depression

• Using techniques from the field of molecular biology, researchers have found evidence that unipolar depression may be tied to specific genes

What Causes Unipolar Depression? The Biological View

Biochemical factors • NTs: serotonin and norepinephrine • In the 1950s, medications for high blood pressure were

found to cause depression • Some lowered serotonin, others lowered norepinephrine

• The discovery of truly effective antidepressant medications, which relieved depression by increasing either serotonin or norepinephrine, confirmed the NT role

• Depression likely involves not just serotonin nor norepinephrine… a complicated interaction is at work, and other NTs may be involved

What Causes Unipolar Depression? The Biological View

Biochemical factors • Endocrine system / hormone release • People with depression have been found to have

abnormal levels of cortisol • Released by the adrenal glands during times of stress

• People with depression have been found to have abnormal melatonin secretion • “Dracula hormone”

• Other researchers are investigating deficiencies of important proteins within neurons as tied to depression

What Causes Unipolar Depression? The Biological View

Biochemical factors • Model has produced much enthusiasm but has certain

limitations: • Relies on analogue studies: depression-like symptoms

created in lab animals • Do these symptoms correlate with human emotions?

• Measuring brain activity has been difficult and indirect • Current studies using newer technology are

attempting to address this issue

What Causes Unipolar Depression? The Biological View

Brain anatomy and brain circuits • Biological researchers have determined that emotional

reactions of various kinds are tied to brain circuits • These are networks of brain structures that work together,

triggering each other into action and producing a particular kind of emotional reaction

• It appears that one circuit is tied to GAD, another to panic disorder, and yet another to OCD

• Although research is far from complete, a circuit responsible for unipolar depression has begun to emerge • Likely brain areas in the circuit include the prefrontal cortex,

hippocampus, amygdala, and Brodmann Area 25

What Causes Unipolar Depression? The Biological View

Immune System • This system is the body's network of activities

and cells that fight off bacteria and other foreign invaders

• When stressed, the immune system may become dysregulated, which some believe may help produce depression • Support for this explanation is circumstantial

but compelling

What Causes Unipolar Depression? The Psychological Views

• Three main models:

Psychodynamic model

• No strong research support

Behavioral model

• Modest research support

Cognitive views

• Considerable research support

What Causes Unipolar Depression? The Psychological Views

Psychodynamic view • Link between depression and grief • When a loved one dies, an unconscious process begins and the mourner

regresses to the oral stage and experiences introjection – a directing of feelings for the loved one onto oneself • For most people, introjection is temporary • For some, grief worsens over time; if grief is severe and long-lasting,

depression results • Those with oral stage issues (unmet or excessively met needs) are at

greater risk for developing depression • Instead of actual loss, some people experience “symbolic” (or imagined) loss

instead • Newer psychoanalysts (object relations theorists) propose that depression

results when people's relationships leave them feeling unsafe and insecure

What Causes Unipolar Depression? The Psychological Views

Psychodynamic view • Strengths: • Studies have offered general support for the

psychodynamic idea that depression may be triggered by a major loss (e.g., anaclitic depression)

• Research supports the theory that early losses set the stage for later depression

• Research also suggests that people whose childhood needs were improperly met are more likely to become depressed after experiencing a loss

What Causes Unipolar Depression? The Psychological Views

Psychodynamic view • Limitations: • Early losses and inadequate parenting

sometimes lead to depression but may not be typically responsible for development of the disorder

• Many research findings are inconsistent • Certain features of the model are nearly

impossible to test

What Causes Unipolar Depression? The Psychological Views

Behavioral view • Depression results from changes in rewards and

punishments people receive in their lives • Lewinsohn suggests that the positive rewards in life

dwindle for some people, leading them to perform fewer and fewer csonstructive behaviors, and they spiral toward depression

• Research supports the relationship between the number of rewards received and the presence or absence of depression • Social rewards are especially important

What Causes Unipolar Depression? The Psychological Views

Behavioral view • Strengths: • Researchers have compiled significant data to

support this theory • Limitations: • Research has relied heavily on the self-reports of

depressed subjects • Behavioral studies are largely correlational and do

not establish that decreases in rewards are the initial cause of depression

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Two main theories: • Negative thinking • Learned helplessness

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Negative thinking • Beck theorizes four interrelated cognitive components

combine to produce unipolar depression: • Maladaptive attitudes • Self-defeating attitudes are developed during

childhood • Beck suggests that upsetting situations later in life

can trigger an extended round of negative thinking

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Negative thinking • Depressed people also make errors in their thinking,

including: • Arbitrary inferences • Minimization of the positive and magnification of the

negative • Depressed people also experience automatic thoughts • A steady train of unpleasant thoughts that suggest

inadequacy and hopelessness

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Strengths: • Many studies have produced evidence in support of Beck's

explanation: • High correlation between the level of depression and the

number of maladaptive attitudes held • Both the cognitive triad and errors in logic are seen in

people with depression • Automatic thinking has been linked to depression

• Limitations: • Research fails to show that such cognitive patterns are the

cause and core of unipolar depression

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Learned helplessness • This theory asserts that people become depressed when

they think that: • They no longer have control over the reinforcements

(rewards and punishments) in their lives • They themselves are responsible for this helpless state

• Theory is based on Seligman's work with laboratory dogs • There has been significant research support for this

model

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Learned helplessness • Recent versions of the theory focus on attributions • Internal attributions that are global and stable lead to greater

feelings of helplessness and possibly depression • Example: “It's all my fault” [internal]. “I ruin everything I

touch” [global] “and I always will” [stable]. • If people make other kinds of attributions, this reaction is

unlikely • Example: “She had a role in this also” [external], “the way I've

behaved the past couple weeks blew this relationship” [specific]. “I don't know what got into me – I don't usually act like that” [unstable].

What Causes Unipolar Depression? The Psychological Views

Cognitive views • Learned helplessness • Strengths: • Hundreds of studies have supported the relationship

between styles of attribution, helplessness, and depression • Limitations: • Laboratory helplessness does not parallel depression in

every way • Much of the research relies on animal subjects • The attributional component of the theory raises particularly

difficult questions in terms of animal models of depression

What Causes Unipolar Depression? The Sociocultural View

• Sociocultural theorists propose that unipolar depression is greatly influenced by the social context that surrounds people – This belief is supported by the finding that

depression is often triggered by outside stressors – There are two kinds of sociocultural views:

• The family-social perspective • The multicultural perspective

What Causes Unipolar Depression? The Sociocultural View

The Family-Social Perspective • The connection between declining social rewards

and depression (as discussed by the behaviorists) is a two-way street • Depressed people often display social deficits

that make other people uncomfortable and may cause them to avoid the depressed individuals

• This leads to decreased social contact and a further deterioration of social skills

What Causes Unipolar Depression? The Sociocultural View

The Family-Social Perspective • Consistent with these findings, depression has been tied repeatedly

to the unavailability of social support such as that found in a happy marriage • People who are separated or divorced display three times the

depression rate of married or widowed persons and double the rate of people who have never been married

• There also is a high correlation between level of marital conflict and degree of sadness that is particularly strong among those who are clinically depressed

• It also appears that people who are isolated and without intimacy are particularly likely to become depressed in times of stress

What Causes Unipolar Depression? The Sociocultural View

The Multicultural Perspective • Two kinds of relationships have captured the interest

of multicultural theorists: • Gender and depression • A strong link exists between gender and depression • Women cross-culturally are twice as likely as men

to receive a diagnosis of unipolar depression • Women also appear to be younger, have more

frequent and longer-lasting bouts, and to respond less successfully to treatment

What Causes Unipolar Depression? The Sociocultural View

The Multicultural Perspective • A variety of theories has been offered: • The artifact theory holds that women and men

are equally prone to depression, but that clinicians often fail to detect depression in men

• The hormone explanation holds that hormone changes trigger depression in many women

• The life stress theory suggests that women in our society experience more stress than men

What Causes Unipolar Depression? The Sociocultural View

The Multicultural Perspective • Two kinds of relationships have captured the interest of

multicultural theorists: • Cultural background and depression • Depression is a worldwide phenomenon, and certain

symptoms seem to be constant across all countries, including sadness, joylessness, anxiety, tension, lack of energy, loss of interest, and thoughts of suicide

• Beyond such core symptoms, research suggests that the precise picture of depression varies from country to country

What Causes Unipolar Depression? The Sociocultural View

The Multicultural Perspective • In addition, although overall depression rates are

similar, differences exist in specific populations living under oppressive circumstances • In a study of one Native American village,

lifetime risk was 37% among women, 19% among men, and 28% overall

• These findings are thought to be the result of economic and social pressures

Bipolar Disorders

• People with a bipolar disorder experience both the lows of depression and the highs of mania – Many describe their lives as an emotional roller

coaster

What Are the Symptoms of Mania?

• Unlike those experiencing depression, people in a state of mania typically experience dramatic and inappropriate rises in mood

• Five main areas of functioning may be affected:

Emotional symptoms

•Active, powerful emotions in search of outlet

Motivational symptoms

•Need for constant excitement, involvement, companionship

Behavioral symptoms

•Very active – move quickly; talk loudly or rapidly •Flamboyance

is not uncommon

Cognitive symptoms

•Show poor judgment or planning •May have

trouble remaining coherent or in touch with reality

Physical symptoms

•High energy level – often in the presence of little or no rest

Diagnosing Bipolar Disorders

• Criteria 1: Manic episode – Three or more symptoms of mania lasting one

week or more • In extreme cases, symptoms are psychotic

• Criteria 2: History of mania – If currently experiencing hypomania or depression

Diagnosing Bipolar Disorders

• DSM-5 distinguishes two kinds of bipolar disorder: – Bipolar I disorder

• Full manic and major depressive episodes – Some experience an alternation of episodes – Others have mixed episodes

– Bipolar II disorder • Hypomanic episodes alternate with major depressive

episodes

Diagnosing Bipolar Disorders

• Without treatment, the mood episodes tend to recur for people with either type of bipolar disorder – If people experience four or more episodes within

a one-year period, their disorder is further classified as rapid cycling

Diagnosing Bipolar Disorders

• Regardless of particular pattern, individuals with bipolar disorder tend to experience depression more than mania over the years – In most cases, depressive episodes occur three

times as often as manic ones, and last longer

Diagnosing Bipolar Disorders

• Between 1% and 2.6% of all adults in the world suffer from a bipolar disorder at any given time, and as many as 4% over the course of their lives – Bipolar I seems to be a bit more common than Bipolar II

• The disorders are equally common in women and men – Women may experience more depressive episodes and

fewer manic episodes than men and rapid cycling is more common in women

• The disorders are more common among people with low incomes than those with high incomes

Diagnosing Bipolar Disorders

• A final diagnostic option: – When a person experiences numerous episodes of

hypomania and mild depressive symptoms, a diagnosis of cyclothymic disorder is assigned

• Mild symptoms for two or more years, interrupted by periods of normal mood

• Affects at least 0.4% of the population • May eventually blossom into bipolar I or II disorder

What Causes Bipolar Disorders?

• Throughout the first half of the 20th century, the search for the cause of bipolar disorders made little progress

• More recently, biological research has produced some promising clues – These insights have come from research into NT

activity, ion activity, brain structure, and genetic factors

What Causes Bipolar Disorders?

• Neurotransmitters – After finding a relationship between low

norepinephrine and unipolar depression, early researchers expected to find a link between high norepinephrine levels and mania

• This theory is supported by some research studies; bipolar disorders may be related to overactivity of norepinephrine

What Causes Bipolar Disorders?

• Neurotransmitters – Because serotonin activity often parallels

norepinephrine activity in unipolar depression, theorists expected that mania would also be related to high serotonin activity

• Although no relationship with high serotonin has been found, bipolar disorder may be linked to low serotonin activity, which seems contradictory…

What Causes Bipolar Disorders?

• Neurotransmitters – This apparent contradiction is addressed by the

“permissive theory” about mood disorders: • Low serotonin may “open the door” to a mood

disorder and permit norepinephrine activity to define the particular form the disorder will take:

– Low serotonin + Low norepinephrine = Depression – Low serotonin + High norepinephrine = Mania

What Causes Bipolar Disorders?

• Ion activity – Ions, which are needed to send incoming

messages to nerve endings, may be improperly transported through the cells of individuals with bipolar disorder

– Some theorists believe that irregularities in the transport of these ions may cause neurons to fire too easily (mania) or to stubbornly resist firing (depression)

• There is some research support for this theory

What Causes Bipolar Disorders?

• Brain structure – Brain imaging and postmortem studies have

identified a number of abnormal brain structures in people with bipolar disorder; in particular, the basal ganglia and cerebellum among others

• It is not clear what role such structural abnormalities play

What Causes Bipolar Disorders?

• Genetic factors – Many theorists believe that people inherit a

biological predisposition to develop bipolar disorders

• Family pedigree studies support this theory: – Identical (MZ) twins = 40% likelihood – Fraternal (DZ) twins and siblings = 5% to 10% likelihood – General population = 1 to 2.6% likelihood

What Causes Bipolar Disorders?

• Genetic factors – Researchers have conducted genetic linkage

studies to identify possible patterns of inheritance – Other researchers are using techniques from

molecular biology to further examine genetic patterns in large families

– Such wide-ranging findings suggest that a number of genetic abnormalities probably combine to help bring about bipolar disorders