Affective Disorders


The different affective disorders include major depressive illness (clinical depression) and mania, minor depressive states, and mood disorders associated with childbirth. The most prevalent of the affective disorders is depression, which refers to both a mood and a psychopathological syndrome. Large random population surveys commonly report that between 10-15 per cent of adults describe themselves as currently feeling at least ‘somewhat depressed’ but a if the label ‘depression’ includes only severe emotional disturbances, the number of cases decreases dramatically, but even major depression is relatively common, affecting 15% of people at some time in their life. (Charney and Weismann, 1988). During the 1980s depression accounted for about one-quarter of all psychiatric hospital admissions in the UK. (Department of Health, 1990).


Seasonal affective disorder is the experience of a mild ‘winter blue’ is now recognised by the DSM. The symptoms associated with this condition include low mood, extreme lethargy and sleepiness, and an increased appetite for food. Women are especially vulnerable, the ratio of women to men diagnosed as suffering from SAD being in the region of 4:1. One aetiological hypothesis suggests that the seasonal depression is owing to high levels of the hormone melatonin, which is secreted by the pineal gland. Environmental light suppresses the secretion of the hormone, but in the winter, the level of natural light is low and the level of melatonin then build op, leading to drowsiness and lethargy (Rosenthal et al. 1984). The light-deprivation hypothesis is supported by the fact that most people diagnosed as suffering from SAD show a substantial improvement after several days of ‘light therapy’ in which they remain for a number of hours each day in artificial daylight. In some cases this seem to restore the person’s energy and to bring about a significant increase in emotional well-being. When the light therapy is stopped, there may be a sudden relapse. (Lewy et al. 1987) Travels to places with more light have tends to lift the depression, whereas travels to places with less light tends to deepen the depression. (Rosenthal et al. 1986)

Clinical depression: Unipolar disorder and bipolar disorder


Unipolar disorder is defined by depression alone, whereas bipolar disorder is defined as depression alternating with mania. The bipolar disorder was formerly labelled ‘manic-depressive disorder’. The depression found here is indistinguishable from that found in cases of unipolar depression. The distinction between unipolar and bipolar forms of affective disorder therefore rests on the occurrence or non-occurrence of manic episodes. In the bipolar disorder, depressed and manic states may follow one another immediately, or they may be separated by periods of normal functioning.

Bipolar disorder: symptoms

In the bipolar disorder, depressed and manic states may follow one another immediately, or they may be separated by periods of normal functioning. Symptoms are the same as for mania and unipolar depression.

Symptoms of unipolar disorder:

Mania is a highly agitated state of mind, often experienced by the individual as euphoria. It is accompanied by hyperactivity, verbosity, and sleeplessness. In many respects, the symptoms of mania are the reverse of those associated with depression. The manic person may display elevated self-confidence, may lack sense of guilt and responsibility, and may find it difficult to stop laughing and giggling. Other symptoms, including delusions and disturbances in sleep patterns, overlap with those of depression, although they usually take very different forms in the two affective states. It is rare for someone to experience manic episodes without also experiencing alternating depressive episodes, but cases of ‘pure mania’ do occur. In practice cases like this may be labelled ‘unipolar mania’, but the term used in the DSM system is all the same ‘bipolar affective disorder’ on the grounds that there is little difference between cases of persistent mania and those of alternating state disorder in terms of their course and treatment.


Mania symptoms

Aetiology: Causes of depression


The aetiological subclassification differentiates cases in which depression is a response to an environmental event (exogenous/reactive depression) and those in which the disorder is not associated with such an event, and is therefore assumed to result from internal (perhaps biological) processes (endogenous depression). It is now accepted that in the majority of cases both endogenous and exogenous factors play a significant aetiological role.


Many people who are depressed are physically run-down, perform poorly on cognitive tasks, are pessimistic and have relationship problems. It is very often difficult to distinguish between the causes of the depression and the effects of the disorder. A depression that has arisen primarily as a reaction to life circumstances may produce physiological changes, which serve to maintain the depression. The existence of such causal relationships between biological and environmental factors reinforces the view that it is often inappropriate to try to make a sharp differentiation between endogenous and exogenous depression.


Whereas some cases appear to be primarily biological in origin, others appear to be triggered by an adverse social or environmental change. In the majority of cases, however, the development and course of the disorder will reflect complex interactions between several biological and psychological factors. There is now clear evidence that changes in the level of certain key neurochemicals can precipitate a depressive episode, and it is equally clear that many cases of clinical depression are triggered by negative events in the person’s life. Family bereavement, divorce, an accident and redundancy from work, for example, all render the individual susceptible to clinical depression. In other cases the depression appears to be a response not to a particular event but to long-term circumstances, which are a continuing source of stress and disappointment.


Despite the general association between stress and depression, many people who are subjected to high stress do not develop a depressive disorder. There are important individual differences in vulnerability, and the risk of becoming depressed is related to a number of biological factors, to the individual’s personality and early history, to cognitive style and coping skills and to the level of available social support.

Biological accounts of depression (aetiology)

The genetic theory

This theory argues that genes are involved in the cause of depression and one of the main ways to investigate this is twin studies. Nurnberger and Gershon (1982) reviewed the results of 7 twin studies and found that the concordance rate for unipolar depression was consistently higher for MZ twins than for DZ twins, thus supporting the hypothesis that genetic factors might predispose people to depression. Across the seven studies reviewed, the average concordance rate for MZ twins was 65 %, whereas for DZ twins it was 14 %. evaluation: The fact that the concordance rate for MZ twins is far below 100 % indicates that depression is not ‘genetically pre-programmed’. The evidence from the genetic studies does nothing to contradict the view that environmental events and acquired psychological characteristics play a crucial role.

Biochemical theories


Much of the current research interest focuses on the idea that depression is caused by a deficiency in certain neurotransmitters, where high levels of neurotransmitter substances lead to the symptoms of mania. Particular attention is now focused on noradrenaline and serotonin. Low levels of these substances could account for many of the symptoms commonly associated with depression. Brain functioning is profoundly affected by neurochemical changes, and a number of animal studies have shown that intense stress reduces levels of noradrenaline. Evidence could also be that drugs known to decrease the level of noradrenaline tend to produce depression in people.


Janowsky et al. (1972) demonstrated that experimental subjects within minutes after having taken a drug called physostigmine became profoundly depressed and experienced feelings of self-hate and suicidal wishes. The fact that a depressed mood can be artificially induced by certain drugs suggests that some cases of ‘natural’ depression might stem from a disturbance in the normal metabolic processes. Furthermore, drugs that increase the available noradrenaline tend to be effective in reducing the symptoms of depression. Such anti-depressants are monoamine oxidase inhibitors and the tricyclics.

The diathesis-stress model
This model is also called the stress-diathesis model and is a development towards an interactionist model of explaining dysfunctional behaviour and it can be a useful tool for integrating the evidence. Factors that appear to affect vulnerability to depression include biological predisposing factors, cognitive style, personality characteristics, and personal history. The stressors which precipitate depression may be rather specific.


Psychological theories of depression (aetiology)


Psychodynamic


Freud suggested that adult vulnerability to depression has its roots in early childhood experiences, and most especially in early experiences of real or imagined loss. The idea that childhood experiences of separation and loss may leave a lifetime vulnerability to sadness, anger and anxiety has remained influential. In his theory of attachment, for example, John Bowlby 1980 places great emphasis on the relevance of loss and rejection in the early years (The attachment Theory). Beck (1967) found support for the theory of loss when he assessed depression in a mixed group of 300 psychiatric patients and found that 27% of those who were highly depressed had lost a parent before the age of 16, and a similar loss had occurred for only 12% of those who were not significantly depressed. Brown and Harris (1978) Childhood loss was found to be an important vulnerability factor in a study concerning the social origins of depression in women. The researchers found that 29 out of 32 women who became depressed had experienced a severe event but 78 percent of those who did experience a severe event did NOT become depressed. He also found that events that matched prior difficulties were more likely to lead to depression and that events that matched prior commitments also more likely to lead to depression. On the basis of this Brown suggested a ‘Vulnerability model’ with the following factors involved that would increase the likelyhood of depression in that 1 out of 5 women who had reported a similar severe event had become depressed. However, vulnerability factors are assumed to increase the probability of depression only if a woman had experienced one of these severe life events:

Behaviourist and behaviourist-cognitive approaches

Skinner (1953). Behaviours which are not positively reinforced (by food, money, social attention etc) tend to disappear form the person’s behaviour repertoire and said to be extinguished. He suggested that the behavioural pattern found in depression might be the result of the ‘extinction’ of positive reinforcement.

Lewinshohn (1974) Later conditioning models of depression placed a special emphasis on the roles played by self-reinforcement and social reinforcement. Social reinforcement may lift the recipient’s mood, making the person feel valued and respected, and those who lack such reinforcements are liable to feel ignored and unloved. Withdrawal from social contact (negative reinforcement) will further reduce the opportunity for receiving social reinforcement, and the vicious circle might therefore develop.

Other learning theory explanations suggest that depression is maintained because of positive reinforcement (the person only gets attention when being depressed).

Seligman (1975) ‘Learned helplessness theory’. People are likely to give up trying to exert influence on the physical and social environment when they find that important aspects of their lives are uncontrollable. When people feel helpless, they are likely to be drained of motivation

  1. The phenomenon of ‘learned helplessness’ was first demonstrated in an experiment where dogs were repeatedly presented with a warning signal followed by a mild electric shock. In the beginning the dogs struggled when they heard the signal, but many soon gave up. When they were later placed in an environment where it was possible to escape from the shock, most of them failed to learn the new adaptive behavioural response. Thus the passive response generalised from the first situation to situations where escape was possible. The animals had learned to be helpless. However, is it possible to generalise findings from animals to humans?
  2. Hiroto and Seligman (1975) showed an analogous effect in humans. The theory offers a useful account of exogenous depression, but it does not provide an explanation for all clinical features associated with this condition, especially the chronicity of depressive disorder, the marked individual differences in vulnerability and for the major loss of self-esteem, which is often a major feature of the condition.
  3. Seligman developed his theory further to meet these shortcomings by using a number of concepts from the field of social cognition, especially those associated with ‘attribution theory’. The revised learned helplessness model emphasises the way in which people perceive and interpret unfavourable events: the attributional style and thus include cognitive explanations: Revised learned helplessness theory, attributional style.
  4. This revised version of the theory focuses on a person’s explanatory style (attributional style) and it predicts that the way people interpret events will affect the risk that an unfavourable event or life circumstance will lead to depression. The theory suggests that those who generally interpret events in a pessimistic and negative way are likely to become depressed. If people tend to make stable internal attributions to explain negative events (‘it’s my fault’), it might explain why depressive episodes tend to exist for a long time. Petersen and Seligman (1984) developed an ‘Attributional Style Questionnaire’ (ASQ) to measure relevant aspects of an individual’s social cognition, and the fact that scores on this test is reliable over time suggests that what is being measured is a relatively stable individual characteristic.
  5. Sweeney et al. (1986) confirmed the findings of Petersen and Seligman in a review of over hundred studies involving nearly 15.000 subjects that showed that the tendency to attribute negative events to internal, stable and global causes is reliably predictive of depression.
  6. Seligman (1996) tried to change people’s attributional style as a means of preventing depression. In one study of ‘learned optimism’, first year university students completed an attributional questionnaire and those who were identified as being among the most pessimistic were invited to participate in the study. They were then randomly assigned either to the control group or to the experimental group. Those in the experimental group attended 16 hours of workshop activity in which they learned to dispute chronic negative thoughts and acquired a number of social and work skills, which might be useful in averting depression. In a follow-up evaluation, some 18 months later, 22% of the workshop participants were found to have suffered moderate of severe depression, compared to 32% of the controls- a highly significant difference. A school-based study also demonstrated that children can be taught to become more optimistic, and that those who acquire highly levels optimism are more self-reliant, more likely to perform well on academic tasks and less likely to become depressed (Seligman, 1996).

Cognitive psychology

It has long been recognised that people who feel depressed tend to think depressed thoughts. It is commonly assumed that the depressed mood is primary, and somehow leads to the cognitive symptoms. Cognitive theories of depression, however, suggests that depressed cognitions are primary and produce the disturbances of mood. The revised learned helplessness model is one of several cognitive models of depression and it emphasises the importance of the perceived uncontrollability of events. Other cognitive models emphasise the role of cognitive distortions and irrational beliefs.


Albert Ellis (1962)‘Cognitive style theory’ suggests that psychological disturbances often come from irrational and illogical thinking. On the basis of dubious evidence or faulty inferences about the meaning of an event, people may draw false conclusions, which then lead to feelings of anger, anxiety or depression. Ellis contends that irrational beliefs (such as ‘I must be competent in everything I do’) together with certain observations (‘I have not performed well on this task’), can easily lead to disheartening conclusions (‘Therefore I am stupid and worthless’).

Rational-emotive behaviour therapy (RET). Ellis’ believed that the emotionally damaging consequences of illogical internalised statements led him to develop a particular approach to therapy (‘rational-emotive therapy’, recently renamed ‘rational-emotive behaviour therapy’. Clients are taught to distinguish between rational and irrational beliefs, and to avoid continual negative, unrealistic, illogical self-defeating thoughts and self-statements.

Research evidence that confirms a close association between negative cognitions and depression:

  1. Ellis and Whiteley (1979) found that people who are depressed tend to have irrational beliefs of the type described by Ellis. Whether unipolar depression originates in maladaptive thinking or whether negative thought patterns are merely symptomatic of depression, it is clear that negative thoughts may help to maintain depression. This is very significant, for whether we assign a ‘causal’ or a ‘maintenance’ role to maladaptive cognitions, it is clear that replacing such cognitions with more positive modes of thinking should help to improve the patients condition.
  2. Beck (1976) developed Seligmans’s theory of ‘learned helplessness’ and suggested a theory of depression that deals with cognitive distortions, errors, and biases in the information processing (negative cognitive triad): ‘cognitive distortion model’.

 

According to Beck, negative cognitive schemata are activated by stressful events and the person over-reacts. In a way, it has to do with the way a person appraises situations, i.e. the attributional style. A person may have negative expectations about the future and may have a tendency to explain these in terms of internal, stable and global factors. The depression may be maintained in a vicious circle. The model has been criticized for claiming that ‘the cognitive triad’ is a stable trait that develops with depression. However, research has shown that attributions fluctuate with mood. Beck sidesteps this problem by saying that the schemas are latent, but this is not an adequate solution. Furthermore, according to some, Beck has no explanation of how the schemas are activated in the first place, but Beck does in fact agree with Seligman that there are usually one or more precipitating events which triggers the development of depression. However, Beck posits that it is these negative life events in combination with a person's vulnerability factor, which determines whether he or she will develop depression. Those people who have a low level of vulnerability may experience stressful life events but may not become depressed; however, if someone with a high vulnerability to depression were to experience the same events, he or she may be more likely to develop depression.


A number of studies have supported Beck’s hypothesis. Joiner et al (1999) measured college students’ dysfunctional attitudes, depressive and anxious cognitions, and depressive symptoms before and after midterm exams. They found that students who had high levels of dysfunctional attitudes and received poor grades on the exams but were not highly vulnerable did not increase in depressive symptoms. The study indicates that attitudes or vulnerability level play an interactive role in determining whether negative life events result in depression. However, the sample were college students (biased) so generalisations may be problematic.


Cross-cultural issues concerning depression

An international study sponsored by WHO points at a common foundation of depressive experience in very different cultural settings. WHO (1983) identified common elements in four different countries: Iran, Japan, Canada and Switzerland. The symptoms were sad affect, loss of enjoyment, anxiety, tension, lack of energy, loss of interest, inability to concentrate, and ideas of insufficiency, inadequacy and worthlessness. These findings are compatible with an earlier study by psychiatrists covering 30 countries Murphy, Wittkower and Chance (1967). This study also found loss of sexual interest, loss of appetite, weight reduction, fatigue, self-accusatory ideas but it did not come up with a clear-cut pattern of universals.

Prince 1968. Earlier reports claimed that there was no depression in Africa and various regions of Asia, but this study found that rates of reported depression rise with Westernisation in the former colonial countries. Depression in non-modernised settings tend to be expressed differently and may escape the attention of a person who is of another culture (Diop, 1967). The negetative symptoms of depression (loss of appetite, insomnia, inability to experience sexual pleasure, fatigue etc.) are present but in most non-Western cultures the experience of guilt is mostly absent

Kleinman (1982) showed that in China somatization served as a typical channel of expression and as a basic component of depressive experience. (somatization=reporting of psychological problems in terms of bodily symptoms such as headaches, back problems etc.) . The Chinese rarely complain of feeling sad or depressed, rather they refer in these communications to the body as the medium of their distress.
De Hoyos and De Hoyos (1965) also showed that middle-class clinicians had problems recognising depression in their Black clients but they were quick to diagnose schizophrenia because of strange behaviour (which they did not know of or understand).


Evaluation: Cross-cultural research has demonstrated that the two most serious psychological disorders exist in all regions of the world and in very different cultures. There is a virtually identical core of symptoms present in both depression and schizophrenia at widely different sites and diverse cultures. However, around this core, there are manifestations that can be meaningfully traced to the characteristics of the milieus in which they occur. These conclusions do not support the extreme positions of universalism and cultural relativism because schizophrenia and depression are not exactly the same the world over. Each culture does not create its own distinct patterns of abnormal behaviour, and the clinician working with a culturally diverse clientele is to combine personal sensitivity with cross-cultural competence and to develop the ability to adapt quickly and realistically to new and different cultural settings.

Depression and gender- a controversial issue:

This deals both with the issue of prevalence (Is it actually true there is a higher rate of women than men who are diagnosed with depression?), the problem of reliability of diagnosis (are the women diagnosed as depressive actually suffering from depression or are there other problems at stake?), and gender stereotyping (also including reliability) (will the doctor be more likely to diagnose a woman as depressed?) In GB a woman is about 40% more likely to be admitted to a psychiatric hospital than a man. Rates of hospitalisation rise rapidly among the elderly, and women outnumber men by 2:1. Depression contributes most to the high overall rate of treated mental illness among women (Cochrane, 1992). Women are 2-3 times more likely to become clinically depressed than men (Williams and Hargreaves, 1995), and they are more likely to experience several episodes of depression.

Are women naturally disposed towards depression?

It is a widely held belief that women are naturally more emotional than men and therefore more vulnerable to emotional upsets because of hormonal fluctuations etc. Williams and Hargreaves (1995) argue that hormonal changes of the menstrual cycle may have an effect in change of mood even though it cannot be said to directly cause depression. Callaghan and O’Carrol (1993) argue that there is some evidence that one in ten women experience post-partum depression but no specific hormonal abnormality has been identified and it is believed that social factors may be important to (adjustment to mother role etc.). Hormonal changes cannot explain discrepancy in female/male rates of depression. If women who have just become mothers are compared to a sample of non-pregnant women of the same age, depression rates are similar (Cooper et al, 1988). Cochrane (1995) claims there is no evidence that physiological changes affect psychological functioning. Cochrane identifies a number of non-biological explanations of women’s greater susceptibility to depression:

Empirical research on gender and depression.

Key study: Brown and Harris (1978) Social origins of depression theory

Many of the aetiological models discussed above, including the psychoanalytic model and the reinforcement model, assign an important role to interpersonal relationships. Several other models focus more specifically on the role of personal relationships in the development and maintenance of depression. Some suggest that problems in childhood may leave an individual particularly vulnerable to depression. In this way these theories address the ‘diathesis’ element of the ‘diathesis-stress’ model. But many relationship theories also focus on the ‘stress’ element and suggest that relationship problems (especially those involving loss, loneliness and conflict) often precipitate the onset of a depressive disorder.


An impressive and highly influential study of social origins of depression was done by Brown and Harris in their book The Social Origins of Depression (1978). They examined the relationship between social factors and depression in a group of women from Camberwell in London. They studied women who had received hospital treatment for depression and women who had visited their physician seeking help for depression. They also studied a general population sample of 458 women aged between 18 and 65 years.


Important: The study found that stressful events often preceded the onset of depression and that it was actually these events that triggered the depression rather than simply bringing forward the onset of a disorder already developing.


The critical importance of severe life events and longstanding ‘severe difficulties’ in the aetiology of depression has been confirmed by the results of nine subsequent studied which have attempted to replicate the original research of Brown and Harris. These studies show that, on average, 82% of those who become depressed have recently experienced at least one severe life event or major difficulty, compared to only 33% of those in non-depressed comparison groups. (Brown and Harris, 1989). The original Brown and Harris study found evidence of a pronounced social class effect, at least for married women. Here are listed some of the other findings in the study:

Evaluation: This study and others following the same line have established that social stress plays a decisive role in triggering many depressive episodes, but it has also demonstrated the fact that social factors may increase an individual’s vulnerability to depression. It also confirms that social support may offer protection against the effects of potentially stressful events. The work described here focuses on objective social events and lifestyle characteristics, but it is also clear that the affective impact of life events is mediated by cognitions (including the person’s evaluation of events) and how the individual try to cope with stress. The cognitive account may help to explain how various vulnerability factors actually operate to increase the risk of depression. Thus the early loss of a mother might engender a general pessimism, so that a stressful event occurring later in life will be perceived as highly threatening. The focus on a diathesis is important.

Efficiency of therapy in depression

Elkin et al, 1989 One of the best-controlled comparative studies was conducted by the National Institutes of Mental Health. This study included 28 clinicians who worked with 280 patients diagnosed as having major depression. Individuals were randomly assigned to treatment using either an antidepressant drug (imipramine), psychodynamic therapy (not psychoanalysis) or cognitive therapy. In addition, a control group was given a placebo pill, together with weekly therapy sessions. The placebo/drug group was conducted as a double-blind design, so that neither the patient nor the doctor knew which was which. All individual were assessed at the start, after 1 weeks of treatment, and after 18 months. The results do not point at a clear-cut result. All three types of treatment produced better improvement than did the placebo, drug therapy gave faster improvements than did insight therapies, but also had higher rates of relapse of symptoms. In the placebo group, some of the individuals with only moderate showed some improvements.

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