1. 5.3 Psychological Disorders
Evaluate psychological research (through theories and studies) relevant to the study of abnormal behaviour
Discuss the interaction of biological, cognitive, and sociocultural factors in abnormal behaviour
Describe symptoms and prevalence of one disorder from two of the following groups: anxiety disorders, eating disorder, affective disorders
Explain cultural and gender variations in disorders.

2. Introduction to psychological disorders.
When discussing abnormal behaviour, psychiatrists and psychologists use a common vocabulary. An important thing to consider is what symptoms an individual exhibits. These are important in making a diagnosis – that is, finding out what the person suffers from.
DSM 1V & ICD 10 diagnose disorders; they do not deal with causes, but, only describe clusters of symptoms.
Symptomology refers to to identification of the symptoms.
It is also important to find out why people suffer from a disorder – that is, the etiology.
When discussing a disorder, there are data which assist in the diagnosis. First, it is important to consider the prevalence rate, which is the measure of the total number of cases of the disorder in a given population.

3. Lifetime prevalence (LTP) is the percentage of the population that will experience the disorder at some stage in their life.
Onset stage is the average age is the average age the disorder is likely to appear. Knowing the average onset age can help how likely it is that a person who begins to show specific symptoms at a specific age can be diagnosed reliably.
We will now look at two disorders one from each of the following classifications.
Affective disorders are characterised by dysfunctional moods. We shall focus on Major Depressive disorder.
Anxiety Disorders have a form of irrational fear as the central disturbance. We shall focus on phobias.

4. Diagnosis of Major Depressive Disorder, Single Episode
Summarized from the Diagnostic and Statistical Manual of Mental Disorders- Fourth Edition, Text Revision
A. The person experiences a single major depressive episode:
For a major depressive episode a person must have experienced at least five of the nine symptoms below for the same two weeks or more, for most of the time almost every day, and this is a change from his/her prior level of functioning. One of the symptoms must be either (a) depressed mood, or (b) loss of interest.
Depressed mood. For children and adolescents, this may be irritable mood.
A significantly reduced level of interest or pleasure in most or all activities.
A considerable loss or gain of weight (e.g., 5% or more change of weight in a month when not dieting). This may also be an increase or decrease in appetite. For children, they may not gain an expected amount of weight.
Difficulty falling or staying asleep (insomnia), or sleeping more than usual (hypersomnia).
Behavior that is agitated or slowed down. Others should be able to observe this.
Feeling fatigued, or diminished energy.
Thoughts of worthlessness or extreme guilt (not about being ill).
Ability to think, concentrate, or make decisions is reduced.
Frequent thoughts of death or suicide (with or without a specific plan), or attempt of suicide.
The persons' symptoms do not indicate a mixed episode.
The person's symptoms are a cause of great distress or difficulty in functioning at home, work, or other important areas.
The person's symptoms are not caused by substance use (e.g., alcohol, drugs, medication), or a medical disorder.
The person's symptoms are not due to normal grief or bereavement over the death of a loved one, they continue for more than two months, or they include great difficulty in functioning, frequent thoughts of worthlessness, thoughts of suicide, symptoms that are psychotic, or behavior that is slowed down (psychomotor retardation).
B. Another disorder does not better explain the major depressive episode.
C. The person has never had a manic, mixed, or a hypomanic Episode (unless an episode was due to a medical disorder or use of a substance).

5. Etiologies of major depressive disorders.
While some cases appear to primarily biological in origin, others seem to be triggered by an adverse social or environmental change. (In groups discuss; what changes in personal circumstance could trigger depression.)
There may be an association between stress and depression, but it is important to point out that many people who are subjected o high levels of stress do not develop a depressive disorder.
It is important to remember that major depression is not caused by a single factor, but stems from a combination of factors. These may include genetic vulnerability, neurotransmitter malfunctioning, psychological problems, or particular life events or lifestyle factors such as drug or alcohol misuse.

6. The Biological Level of Analysis.
First of all review and revise the key concepts and ideas of this etiology. (genetics/neurotransmitters/hormones.
Summerise key studies and theories in your workbook.
Nurnberger and Gershon (1982) twin studies.
Duenwald (2003) 5-HTT gene.
Deficiency in neurobiological systems such as neurotransmitters and hormones. Joseph Schildkraut suggested the catechololamine hypothesis linked to levels of serotonin and noradrenaline.

7. Supported by Delgado and Moreno.
Rampello (2000) found patients with MDD have an imbalance of several neurotransmitters. Not supported by Burns (2003)
Serotonin hypothesis
Cortisol hypothosis.