Emotional Responses and Mood Disorders



Emotional Responses and Mood Disorders


Gail W. Stuart





Variations in emotions and mood are a natural part of life. They indicate that a person is perceiving the world and responding to it. Extremes in mood also are linked with extremes in human experience, such as creativity, madness, despair, ecstasy, romanticism, personal charisma, and interpersonal destructiveness.


Mood is a prolonged emotional state that influences the person’s whole personality and life functioning. It is similar to the terms feeling state and emotion. Like other aspects of the personality, emotions or moods serve an adaptive role. The four adaptive functions of emotions are social communication, physiological arousal, subjective awareness, and psychodynamic defense.



Continuum of Emotional Responses


Emotions such as fear, joy, anxiety, love, anger, sadness, and surprise are all normal parts of the human experience. The problem arises in trying to evaluate when a person’s mood or emotional state is maladaptive, abnormal, or unhealthy.



LEARNING FROM A CLINICAL CASE


This case can help you understand some of the issues you will be reading about. Read the case background and then, as you read the chapter, think about your answers to the Case Critical Reasoning Questions. Case outcomes are presented at the end of the chapter.



Case Background


She was referred from a local college and they wanted her to be seen right away. They were concerned because she has been exercising for hours each day. She had a sudden weight loss and they were thinking she might have anorexia.


She appeared in bright pink pants, orange flowered top, and heavy makeup. She was delightful and charming, but after 10 minutes she started to cry. She said that she was very confused. At first she was feeling just fine, but now she was very upset. Her mother was traveling to her college and planned on staying a couple of days. She was concerned that her mother might have a wreck while driving to see her. Then she changed the subject and began talking very fast about a friend who had had a car wreck a year ago that was fatal. Her mother would be traveling on the same interstate highway and the same thing might happen to her mother. She said she worries about it all the time and has not been able to sleep much in the past few weeks.


Again, almost as quickly, she began talking about her boyfriend whom she would see in a month. He was attending another college and was coming for a party weekend. She said no one has ever loved her the way he does. He treats her like a queen. She then went back to talking about the friend who had died in the car crash, saying that she had had a premonition that something bad was going to happen. She said she is psychic that way and knows what is going to happen in other people’s lives.


She began to cry, mumbling that she should have been able to save her friend’s life. She should have been able to tell her that something bad was going to happen. Maybe her friend wouldn’t have gone on the trip. Maybe she would still be alive. She should have helped her.



Grief, for example, is a healthy, adaptive, separating process that attempts to overcome the stress of a loss. Grief work, or mourning, is not a pathological process; it is an adaptive response to a real stressor. The absence of grieving in the face of a loss suggests maladaptation.


The continuum of emotional responses is shown in Figure 18-1.




• At the adaptive end is emotional responsiveness. It implies an openness to and awareness of feelings. In this way, feelings provide us with valuable learning experiences. They are barometers that give us feedback about ourselves and our relationships, and they help us function more effectively.


• Also adaptive in the face of stress is an uncomplicated grief reaction. Such a reaction implies that the person is facing the reality of the loss and is immersed in the work of grieving.


• A maladaptive response is the suppression of emotions. This may be a denial of one’s feelings or a detachment from them. A temporary suppression of feelings may at times be necessary to cope, as in an initial response to a death or tragedy.


• Delayed grief reaction also is maladaptive. It involves a prolonged suppression of emotion that interferes with effective functioning.


• The most maladaptive emotional responses are depression and mania seen in bipolar disorder. Severe mood disturbances are recognized by their intensity, pervasiveness, persistence, and interference with social and physiological functioning.



Grief Reactions


Grief is the subjective state that follows loss. It is one of the most powerful emotional states and affects all aspects of a person’s life. It forces the person to stop normal activities and focus on present feelings and needs. Most often, it is the response to the loss of a loved person through death or separation, but it also can follow the loss of something tangible or intangible that is highly regarded. It may be a valued object, a cherished possession, an ideal, a job, or status.


As a response to the loss of a loved one, grief is a universal reaction. As a person’s dependence on others grows, the chance increases that the person will at some point face loss, separation, and death, which elicit intense feelings of grief. The capacity to form warm, satisfying relationships with others makes a person vulnerable to sadness, despair, and grief when those relationships are terminated.


As a natural reaction to a life experience, grief is universal; however, the way in which it is expressed is culturally determined. Grief involves stress, pain, suffering, and an impairment of function that can last for days, weeks, or months. Understanding the stages of grief and its symptoms is important because of grief’s effect on both physical and emotional health.


The ability to experience grief is gradually formed in the course of normal development and is closely related to the capacity for developing meaningful relationships. Grief responses may be adaptive or maladaptive.



• Uncomplicated grief is an adaptive response. It runs a consistent course that is modified by the abruptness of the loss, the person’s preparation for the event, and the significance of the lost object. It is a self-limited process of realization; it makes real the fact of the loss.


• Delayed grief reaction is maladaptive. Something is preventing the grief from running its normal course. Persistent absence of any emotion signals a delay in the work of mourning. This delay may occur in the beginning of the mourning process, slow the process once it has begun, or both. The delay and rejection of grief may occasionally last for many years.


• Bereavement and loss also can be seen in the maladaptive response of depression. It is an abnormal extension or overelaboration of sadness and grief (Kendler et al, 2008).


The emotions associated with the loss may be triggered by a deliberate recall of circumstances surrounding the loss or by a spontaneous occurrence in the patient’s life. A classic example of this is the anniversary reaction, in which the person experiences incomplete or abnormal mourning at the time of the loss, only to have the grieving response recur at anniversaries of the original loss.



Depression


Depression is the oldest and most common psychiatric illness. The word depression is used in a variety of ways. It can refer to a sign, symptom, syndrome, emotional state, reaction, disease, or clinical entity (Ayuso-Mateos et al, 2010). In this chapter depression is viewed as a clinical disorder that is severe, maladaptive, and incapacitating.


Depression may range from mild and moderate states to severe states with or without psychotic features. Psychotic depression is uncommon, accounting for fewer than 10% of all depressions. Depression can begin at any age, and symptoms develop over days, weeks, and months.


Approximately one of eight adults experiences major depression during their lifetime. Depression affects 14 million people each year, 70% of whom are women. Complications include significant marital, parental, social, and work difficulties. It has been estimated that depression costs the U.S. economy $43 billion in worker absenteeism, lost productivity, and health care.


The lifetime risk for major depression is 7% to 12% for men and 20% to 30% for women. Among women, rates peak between adolescence and early adulthood. This difference holds true across cultures and continents. Other risk factors include a history of depressive illness in first-degree relatives and a history of major depression.


As a psychiatric illness, depression exists in all countries. The World Health Organization has identified depression as the number one psychiatric cause of disability in the world and has projected that it will rank second in the world as a cause of disability by 2020.


Culture affects the symptomatic expression, clinical presentation, and effective treatment of depression (Jang et al, 2010) (Box 18-1). Culture has an effect on the neural systems, psychological states, and interpersonal patterns that exist throughout one’s life, and cultural variations in family and child-rearing practices shape one’s view of the world. Culture provides a release for emotional expression and also can influence one’s source of distress, the form of illness experienced, modes of coping with distress, help-seeking behavior, and social response.



BOX 18-1   SOCIOCULTURAL CONTEXT OF CARE


How Does Culture Impact Depression?


In some cultures, disturbances of mood are viewed as moral problems, whereas in others they are repressed or seen as a sign of personal failure or lack of personal strength. This can lead some cultures to deny or minimize this aspect of personal distress.


In the United States, the prevalence of depression is associated with income inequality: the more unequal it is, the higher the depression prevalence (Messias et al, 2011). Racial and ethnic minorities are less likely to receive appropriate care because of underdiagnosis and undertreatment (Kozhimannil et al, 2011). Other barriers to care include lack of insurance, scarcity of minority providers, and distrust of care providers. Clearly, clinicians need to work collaboratively with their patients, as well as with culture brokers and colleagues from other cultural communities, not only to better understand and identify their patients’ problems and eliminate disparities in care but also to uncover cultural resources that can complement and perhaps supplant conventional treatment.


There have been changes in attitudes about the causes and treatment of depression among the American public in the past decade. More people now believe in a biological basis for the disorder (Blummer and Marcus, 2009). This may lead to more effective outreach, prevention, and education efforts.


Most untreated episodes of major depression last 6 to 24 months. Some people have only a single episode of major depression and return to presymptomatic functioning. However, more than 50% of those who have one episode will eventually have another, and 25% of patients will have chronic, recurrent depression.


Depression often occurs along with other psychiatric illnesses (Table 18-1). Up to 40% of patients with major depressive disorders have histories of one or more nonmood psychiatric disorders that significantly impair their quality of life. These statistics underscore the importance of this health problem and suggest the need for timely diagnosis and treatment. Unfortunately, only one third of all people with depression seek help, are accurately diagnosed, and obtain appropriate treatment (Mojtabai, 2009).



A high incidence of depression is found among all patients hospitalized for medical illnesses. Its intensity and frequency are higher in more severely ill patients (Lin et al, 2010; Fallon, 2011). These depressions are largely unrecognized and untreated by general health care providers.


Studies suggest that about one third of medical inpatients report mild or moderate symptoms of depression, and up to one fourth have major depression. Medical conditions often associated with depression include diabetes, cancer, stroke, epilepsy, multiple sclerosis, Parkinson disease, cardiac disease, end-stage renal disease, and a variety of endocrine disorders.



Depressive conditions are highly prevalent in primary care settings. It is one of the most common clinical problems. One of every five patients seeing a primary care practitioner has significant symptoms of depression and one in ten patients meet criteria for major depressive disorder (Halaris, 2011). Yet health care providers fail to diagnose major depression in their patients up to 50% of the time.


Given the prevalence and disability associated with depression, the U.S. Preventive Services Task Force (2010) has recommended screening of adults for depression in primary care settings that have systems in place to ensure accurate diagnosis, effective treatment, and responsive follow-up.


It is particularly important to screen for depression among women of reproductive age, especially those who have children or plan to become pregnant. This is because major depression during pregnancy can result in negative fetal outcomes, impaired neurocognitive and socioemotional development of the child, and increased risks of mental and medical disorders in the offspring later in life (Bansil et al, 2010). Simply stated, children of depressed mothers suffer. Yet, with appropriate diagnosis, mothers can be successfully treated, with improved functioning in their offspring (Pilowsky et al, 2008).




Bipolar Disorder


In the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR; American Psychiatric Association, 2000), the major mood disorders are separated into two groups—bipolar and depressive disorders—based on the involvement of manic and depressive episodes over time.



Manic episodes can vary in intensity from moderate manic states to severe and panic states with psychotic features. Mania is characterized by an elevated, expansive, or irritable mood. Hypomania is a clinical syndrome that is similar to but not as severe as mania.


Bipolar disorders are less common than depressive disorders. It is estimated that 2.6% of the adult population has bipolar disorder (Wieseke et al, 2011). Risk factors are being female and having a family history of bipolar disorder.


Most people start showing signs of bipolar disorder in their late teens (average age at onset, 21 years). The data suggest that people younger than 50 years of age are at higher risk of a first attack, whereas those who already have the disorder face increased risk of a recurrent manic or depressive episode as they grow older (Sorrell, 2011).


On average, a person is free of symptoms for about 5 years between the first and second episodes. The interval between episodes may shorten over time, especially if treatment is discontinued too soon. It is estimated that a person with bipolar disorder will have an average of eight to nine mood episodes during his or her lifetime.


Bipolar disorders are associated with increased premature mortality secondary to general medical illnesses (Roshanaei-Moghaddam and Katon, 2009; Weber et al, 2011). Unhealthy lifestyle, biological factors, adverse medication effects, and disparities in health care are contributing factors. Additional facts about depressive and bipolar disorders are presented in Box 18-2.





Assessment


Behaviors


Behaviors Associated With Delayed Grief Reaction


Delayed grief reactions may be expressed by excessive hostility and grief, prolonged feelings of emptiness and numbness, an inability to cry or express emotions, low self-esteem, use of present tense instead of past when speaking of the loss, persistent dreams about the loss, retention of clothing of the deceased, an inability to visit the grave of the deceased, and projection of living memories onto an object held in place of the lost one. The following clinical example illustrates some of the behaviors associated with a delayed grief reaction.



In this example, Ms. G was experiencing a delayed grief reaction precipitated by the event of her deceased son’s would-be graduation. She had failed to progress through mourning after her son’s death and was just now beginning grief work.



Behaviors Associated With Depression


The behaviors associated with depression vary. Sadness and slowness may predominate, or agitation may occur. The key element of a behavioral assessment is change. Depressed people change their usual patterns and responses. This often leads them to seek help.


Behaviors associated with depression include affective, physiological, cognitive, and behavioral responses. Box 18-3 presents the spectrum of possible behaviors. Not all patients experience all of these behaviors.



The most common and central behavior is that of depressed mood. This is not necessarily described by the patient as depression but rather as feeling sad, blue, down in the dumps, unhappy, or unable to enjoy life. Crying often occurs. On the other hand, some depressed people do not cry and describe themselves as “beyond tears.” The mood disturbance of the depressed patient resembles that of normal unhappiness multiplied in intensity and duration.


Another mood that often accompanies depression is anxiety: a sense of fear and intense worry. Both depression and anxiety may show diurnal variation, that is, a pattern whereby certain times of the day, such as morning or evening, are consistently worse or better.


Other patients may initially deny their anxious or depressed moods but do identify a variety of somatic complaints. These might include gastrointestinal distress, chronic or intermittent pain, irritability, palpitations, dizziness, appetite change, lack of energy, change in sex drive, or sleep disturbances. The person often focuses on these symptoms because they are more socially acceptable than the profound feeling of sadness, inability to concentrate, or loss of pleasure in usual activities.


In addition, the physical symptoms may help the person with depression explain why nothing is fun anymore. When patients have a range of somatic symptoms, the nurse should carefully evaluate these complaints but also should return to the issues of mood and loss of interest, thus considering the possible diagnosis of depression.


Two subgroups of major depressive disorder deserve special attention.



Postpartum onset

Postpartum mood symptoms are divided into three categories based on severity: blues, depression, and psychosis.



1. Postpartum blues are brief episodes, lasting 1 to 4 days. They occur in about 50% to 80% of women within 1 to 5 days of delivery. Women have labile mood and tearfulness. Treatment consists of reassurance, social support, adequate sleep, and time to resolve this normal response.


2. Postpartum depression may occur from 2 weeks to 12 months after delivery but usually occurs within 6 months. The risk of postpartum depression is 10% to 15%, but the rate is higher for women with a history of psychiatric disorders. Treatment with medication and psychotherapy is indicated for postpartum depression, because treatment has positive effects on both mother and baby (Meltzer-Brody et al, 2008; Pilowsky et al, 2008).


3. Postpartum psychosis typically begins 2 to 3 days after delivery, with highest risk during the first month. It can be divided into depressed and manic types. The incidence of postpartum psychosis is low, and the prognosis is good for acute postpartum psychosis if it is treated at its onset. Psychiatric hospitalization is usually required to protect the mother and her baby (Friedman et al, 2009). Many patients go on to develop bipolar disorder (Spinelli, 2009). The recurrence rate is 33% to 51%, underscoring the importance of early intervention.




Suicide


The potential for suicide should always be assessed in those with severe mood disturbances. Suicide and other self-destructive behaviors are discussed in detail in Chapter 19. Previous suicide attempts and poor social support indicate risk, however the time spent depressed is a major factor in determining long-term risk of suicide (Holma et al, 2010).



The intensity of anger, guilt, and worthlessness may precipitate suicidal thoughts, feelings, or gestures, as illustrated in the following clinical example.



CLINICAL EXAMPLE


Mr. W was a 68-year-old man who lived alone. His son and daughter were married and lived in the same state. His wife had died 2 years before, and since that time his children had often asked him to move in with either of them. He consistently refused to do this, believing that he and his children needed privacy in their lives. Six months before, he was diagnosed as having advanced prostatic cancer with metastasis. After the diagnosis and because of increasing disability, he left his job and began to receive disability compensation. He visited his children and their families about twice each month and kept his regularly scheduled visits with the medical clinic.


The nurses and physicians at the clinic noted that he was “despondent and withdrawn” but thought this was a normal reaction to his diagnosis and family history. No interventions were implemented based on his emotional needs. A week after attending the clinic for a routine follow-up visit, he went to the cemetery where his wife was buried and at her gravestone shot himself in the head. The groundskeeper of the cemetery heard the shot, discovered what had happened, and called an ambulance. Mr. W was taken to the emergency room of the nearest hospital and, with prompt medical care, survived the suicide attempt.



This example highlights three important points:




Behaviors Associated With Bipolar Disorder


Manic behavior, the essential feature of bipolar disorder, is a distinct period of intense psychophysiological activation. Some of these behaviors are listed in Box 18-4. The predominant mood is elevated or irritable. It is accompanied by one or more of the following symptoms: hyperactivity, the undertaking of too many activities, lack of judgment in anticipating consequences, pressured speech, flight of ideas, distractibility, inflated self-esteem, and hypersexuality.



If the mood is elevated or euphoric, it can be infectious. Patients report feeling happy, unconcerned, and carefree. Although such experiences seem desirable, the person also has no concern for reality or the feelings of others. Patients may have misperceptions about their power and importance and may involve themselves in senseless, irresponsible, or risky activities.


Alternatively, the mood may be irritable, especially when plans are blocked. Patients can be argumentative and provoked by seemingly harmless remarks. Self-esteem is inflated during a manic episode, and as the activity level increases, feelings about the self become increasingly disturbed. Grandiose symptoms are evident. The patient is willing to undertake any project possible.


In contrast to depressed patients, bipolar patients are extremely self-confident, with an ego that knows no bounds; they are “on top of the world.” Accompanying this magical omnipotence and supreme self-esteem is a lack of guilt and shame. Often they deny realistic danger. The patient’s boundless energy and inability to anticipate consequences often lead to irresponsible activities and excessive spending, as well as problems of a sexual, aggressive, or possessive nature.


Bipolar patients have abundant energy and heightened sexual appetite. Physical changes they experience are caused by inadequate nutrition, partly because manic patients have no time to eat. Serious weight loss is also related to their insomnia and overactivity. Extremely manic patients may become dehydrated and require prompt attention.


The person with bipolar illness may exhibit disturbed speech patterns. As mania intensifies, formal and logical speech is replaced by loud, rapid, and confusing language. This is often referred to as pressured speech. As the activated state increases, speech includes numerous plays on words and irrelevancies that can escalate to loose associations and flight of ideas (see Chapter 6). Some of these behaviors are seen in the following clinical example.



Another behavior associated with bipolar disorder is lability of mood with rapid shifts to periods of depression. This accounts for patients who are alternately happy and sad. There may be feelings of guilt and thoughts of suicide.


Manic episodes are very likely to recur. About 75% of bipolar patients have more than one manic episode, and almost all those with manic episodes also have depressive episodes. However, the duration and severity of the manic episodes vary among patients, as do the intervals between relapses and recurrences.


Finally, disturbances of mood are interrelated with self-esteem problems and disrupted relationships. Multiple aspects of the patient’s life are affected, including physical health. Hypertensive crises, irritable bowel syndrome, coronary occlusions, rheumatoid arthritis, migraine headaches, and various dermatological conditions can occur with severe mood disturbances.



Predisposing Factors


Genetics


Both heredity and environment play an important role in severe mood disturbances (Zimmermann et al, 2011). Major depression and bipolar disorder are familial disorders, and their familiarity primarily results from genetic influences.


The lifetime risk is 20% for relatives of people with depression and 24% for relatives of people with bipolar disorder. The lifetime risk for mood disorders in the general population is 6%. A person who has an identical (monozygotic) twin with an affective disorder has a two to four times greater risk for the disorder than if the sibling were a fraternal (dizygotic) twin or nontwin. Therefore good evidence exists for the role of genetic factors in mood disorders (Breen et al, 2011; Hamilton, 2011).



Object Loss Theory


The object loss theory refers to traumatic separation of the person from significant objects of attachment, particularly loss during childhood as a predisposing factor for adult depressions. It proposes that a child has ordinarily formed a tie to a significant other by 6 months of age, and if that tie is broken in early life, the child experiences separation anxiety, grief, and mourning. This mourning in the early years can predispose the child to psychiatric illness, or it can be beneficial and help develop resilience.


This theory also focuses attention on the negative impact of maternal depression on infants and children. This is expressed by the infant as flat affect, lower activity, disengagement, and difficulty in being consoled. Among older children it is seen as sadness, submissive helplessness, and social withdrawal.


Poorer maternal and fetal outcomes are associated with maternal depression (Pilowsky et al, 2008; Bansil et al, 2010). This underscores the need for early interventions by nurses for parents experiencing depression and for their children (Horowitz et al, 2009; Connelly et al, 2010).




Personality Organization Theory


The personality organization view of mood disorders focuses on the major psychosocial variable of low self-esteem. The patient’s self-concept is an underlying issue, whether it is expressed as dejection and depression or as overcompensation with supreme competence, as displayed in manic and hypomanic episodes. Threats to self-esteem arise from poor role performance, perceived low-level everyday functioning, and the absence of a clear self-identity.


There are three forms of personality organization that could lead to depression (Arieti and Bemporad, 1980). They emphasize the critical importance of self-concept and the patients’ appraisal of their life situation.




Cognitive Model


The cognitive model proposes that people experience depression because their thinking is disturbed (Beck et al, 1979; Beck, 2008). Depression is seen as a cognitive problem arising from a person’s negative view of self, the world, and the future.


The depression-prone person, according to this theory, is likely to explain an adverse event as a personal shortcoming. For example, the deserted husband believes that “she left me because I’m unlovable” instead of considering other possible alternatives, such as personality incompatibility, the wife’s own problems, or her change of feelings toward him. As he focuses on his personal deficiencies, they expand to the point where they completely dominate his self-concept. He can think of himself only in a negative way and is unable to acknowledge his strengths, achievements, and abilities. This negative set is reinforced when he interprets all experiences as further proof of his deficiencies. Comparisons with other people further lower his self-esteem, and every encounter with others becomes a negative experience. His self-criticisms increase as he views himself as deserving of blame.


Depressed patients become dominated by pessimism. Their predictions tend to be overgeneralized and extreme. Because they see the future as an extension of the present, they expect their failure to continue permanently. Thus pessimism dominates their activities, wishes, and expectations.


Depressed people are capable of logical self-evaluation when not in a depressed mood or when only mildly depressed. When depression does occur, after some precipitating life stressors, the negative cognitive set makes its appearance. As depression develops and increases, the negative thinking increasingly replaces objective thinking.


Although the onset of the depression may appear sudden, it develops over weeks, months, or even years, as each life experience is interpreted as further evidence of failure. As a result of this tunnel vision, depressed people become hypersensitive to experiences of loss and defeat and oblivious to experiences of success and pleasure. They have difficulty acknowledging anger because they think they are responsible for, and deserving of, insults from others and problems encountered in living.


Along with low self-esteem, they experience apathy and indifference. They are drawn to a state of inactivity and withdraw from life. They lack spontaneous desire and wish only to be passive. Because they expect failure, they lack the ordinary energy to even make an effort.


Suicidal wishes can be seen as an extreme expression of the desire to escape. Suicidal patients see their life as filled with suffering, with no chance of improvement. Given this negative mind set, suicide seems a rational solution. It promises to end their misery and relieve their families of a burden, and they begin to believe that everyone would be better off if they were dead. The more they consider the alternative of suicide, the more desirable it may seem, and as life becomes more hopeless and painful, the desire to end it becomes stronger.




Learned Helplessness-Hopelessness Model


Helplessness is a “belief that no one will do anything to aid you.” Hopelessness is a “belief that neither you nor anyone else can do anything.” This theory proposes that it is not trauma that produces depression but the belief that one has no control over important outcomes in life (Seligman, 1975; Abramson et al, 1989).


Learned helplessness is both a behavioral state and a personality trait of one who believes that control over reinforcers in the environment has been lost. These negative expectations lead to hopelessness, passivity, and an inability to assert oneself.




Behavioral Model


The behavioral model views people as being capable of exercising control over their own behavior (Lewinsohn et al, 1979). They do not merely react to external influences; they select, organize, and transform incoming stimuli. Thus people are not viewed as powerless objects controlled by their environments; nor are they absolutely free to do whatever they choose. Rather, people and their environments affect each other.


The concept of reinforcement is crucial to this view of depression. Person-environment interactions with positive outcomes provide positive reinforcement. Such interactions strengthen the person’s behavior. Little or no rewarding interaction with the environment causes the person to feel sad. The key assumption in this model is that a low rate of positive reinforcement leads to depressive behaviors.


Two elements of this model are important. One is that the person may fail to produce appropriate responses that will result in positive reinforcement. The other is that the environment may fail to provide reinforcement and thus worsen the patient’s condition. This occurs because depressed patients are often deficient in the social skills needed to interact with others effectively. In turn, other people find the behavior of depressed people distancing, negative, or offensive and therefore often avoid them as much as possible.


Depression is likely to occur if the following positively reinforcing events are absent:




These may be described by phrases such as “being with friends,” “being relaxed,” “doing my job well,” “being sexually attractive,” and “doing things my own way.”


Depression also can occur if the following punishing events are present:



The behavioral model of depression emphasizes an active approach. Treatment is aimed at helping the person increase the quantity and quality of positively reinforcing events and decrease punishing events.




Biological Model


The biological model explores chemical changes in the body during depressed states. No single biochemical model adequately explains the causes of mood disorders.


Abnormalities are seen in many body systems during a depressive illness, including electrolyte disturbances (especially of sodium and potassium); neurophysiological alterations; dysfunction and faulty regulation of autonomic nervous system activity; adrenocortical, thyroid, and gonadal changes; and neurochemical alterations in the neurotransmitters, especially in the biogenic amines, which act as central nervous system and peripheral neurotransmitters. The biogenic amines include three catecholamines—dopamine, norepinephrine, and epinephrine—as well as serotonin and acetylcholine (Krishnan and Nestler, 2010).



Endocrine system

Some symptoms of depression that suggest endocrine changes are decreased appetite, weight loss, insomnia, diminished sex drive, gastrointestinal disorders, and variations of mood. Mood changes also have been observed with a variety of endocrine disorders, including Cushing disease, hyperthyroidism, and estrogen therapy (Howland, 2010). Further support for this theory is evident in the high incidence of depression during the postpartum period, when hormonal levels change.


Current study of neuroendocrine factors in mood disorders emphasizes the disinhibition of the hypothalamic-pituitary-adrenal (HPA) axis and the hypothalamic-pituitary-thyroid (HPT) axis. Two tests based on the neuroendocrine theory and performed clinically may prove to be useful in diagnosing affective illnesses.



These tests may be helpful in differentiating unipolar from bipolar depression and mania from schizophrenic psychosis.




Neurotransmission

One of the dominant theories in the neurobiology of mood disorders is the dysregulation hypothesis. It proposes that a problem exists in several of the neurotransmitter systems.


Substantial evidence exists for abnormal regulation of the serotonin (5-HT) neurotransmitter system (Figure 18-2). This dysregulation is in the amount or availability of 5-HT, the sensitivity of its receptors in relevant regions of the brain, and its balance with other neurotransmitters and brain chemicals.








Brain imaging

Computed tomography (CT) and magnetic resonance imaging (MRI) studies find various abnormalities in the structure of brains in people with mood disorders.



Positron emission tomography (PET) studies of mood disorders show decreased frontal lobe brain metabolism (hypometabolism), which is more pronounced on the left hemisphere in depression and on the right hemisphere in mania. This means that the frontal lobes, which have an important role in intellectual and emotional activities, are not using as much glucose as they should (Figure 18-3).



Prefrontal cortex (PFC) hypometabolism affects the function of many brain structures that are connected with the PFC by way of the 5-HT system. These interconnections contribute to the varied symptoms of depression (Table 18-2). Also, the amygdala shows increased blood flow, which is associated with intrusive ruminations in people with severe recurrent depression and a family history of mood disorders.



TABLE 18-2


PREFRONTAL CORTEX AND SEROTONIN INTERCONNECTIONS: IMPLICATIONS IN DEPRESSION


































INTERCONNECTED BRAIN STRUCTURES HYPOTHESIZED ROLE OF THESE INTERCONNECTIONS IN DEPRESSION
Prefrontal Cortex Covering the frontal lobes, it is unique within the central nervous system (CNS) for its strong interconnections with all other areas of the brain; it receives information that has already been processed by other sensory areas and then merges this information with other emotional, historical, or relevant information, thus attending to both feelings and intellect.
Limbic System Structures The prefrontal cortex modulates limbic system activities (emotional and instinctive) by way of the following three structures:
Hippocampus Major importance in cognitive function, including memory
Amygdala Major importance in modulating feelings such as aggression, anger, love, and shyness
Cingulate gyrus Involved in motivation and interest
Brainstem Responsible for regulating the general state of arousal and tone of brain function; also the location of structures that manufacture various neurotransmitters, such as serotonin (5-HT), norepinephrine (NE), and dopamine (DA).
Raphe Nuclei Located in the brainstem, they manufacture 5-HT; they also modulate excessive stimuli and the organization and coordination of appropriate responses to these stimuli.
Hypothalamus This interconnection allows for direct prefrontal input into neuroendocrine function by way of the hypothalamic-pituitary axis (HPA).
Suprachiasmatic Nucleus Located in the hypothalamus, it regulates circadian (24-hour) rhythms and circannual rhythms; thus it is also implicated in seasonal affective disorder (SAD).

Feb 25, 2017 | Posted by in NURSING | Comments Off on Emotional Responses and Mood Disorders
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