Analyse etiologies (in terms of biological, cognitive and/or sociocultural factors) of one disorder from two of the following groups: anxiety disorders, affective disorders, eating disorders.

Etiology is the study of the causes or origins of a disease.

Major Depression

Biological
There are several genetic and biochemical factors in depression. There are certain genes that have found to have links with depression such as the short allele of the 5-HTT gene (Caspi 2003).
There is a study that supports the existence of this factor. That study is Caspi et. al. (2003) The aim of this study was to investigate the relationship between the 5-HTT gene (Seretonin transporter gene) and depression. The participants were 847 Caucasian New Zealanders. The study went by having participants give self-reports on depression and cross-check it with their friends (To check the honesty of the participants). The results show that having a short allele of the 5-HTT gene correlated with increased vulnerability for depression between the ages of 21-26. The results of this study clearly shows that biological factors such as genes can be the underlying causes of many diseases such as depression. This study is high in external reliability but is rather difficult to replicate. The study though is valid although may not be generalizable because only the participants were only New Zealanders. Ecological validity is also not very high because the study is not very realistic.

Cognitive
There is several cognitive factors in depression. Firstly, a depressed mood may lead to depressed thoughts. On the other hand, depressed cognitions, cognitive distortions and irrational beliefs can produce disturbances in the mood.
There are many studies that support the existence of this factor in depression. One of those is Goldapple (2004). The aim of this study was to investigate how cognitive therapy affects brain changes. In this study, the brain activity before and after 15-20 therapies of cognitive therapies over seven weeks of fourteen different patients were documented using a PET scan. PET scans from a previous study on participants taking antidepressants were used as a control group. Other controls were that participants were screen to ensure that they had no substance problems or antidepressant treatment within one month prior to the study. The results were fascinating as there were significant changes in glucose metabolism in prefrontal-hippocampal pathways. The changes to the brain were similar as those patients who took antidepressants. This experiment is difficult to replicate. However, it is highly valid and high in ecological validity because PET scans are used in everyday life.

Sociocultural
Social and cultural factors affect the prevalence and manifestation of the disorder
There are many studies that support the existence of this factor. One of those is Brown and Harris (1978). In this study, Brown and Harris examined the relationship between social factors and depression in a group of women from Camberwell in London. They studied women who had recieved hospital treatment for depression or consulted a doctor about depression. They also studied a general population sample of 458 women aged between 18-65 years old. They found that on average, 82% of those who became depressed recently had encountered a traumatic life event. In the normal group however, only 33% of the women had encountered a serious life event recently. The study also found that working women were at a greater risk of depression than women who stayed at home. It was also found out that women with children have a greater risk of depression as well. Women that were recently widowed, divorce or separated also have a relatively higher chance of suffering from depression. Nevertheless, not all women who have had life difficulties became depressed. In fact, only about 20% of women who experienced life difficulties became depressed. This suggested that people differ in their vulnerability and there are many 'vulnerability factors' such as a lack of confidante, early loss of mother or being unemployed. One of the most protecting factors against depression was found to be the presence of a partner. Another study is

Cutrona et al, (2006)
Aim
To investigate how environment, personality and life stressors contribute to depression
Sample
720 Afro-American women
Procedure
Survey
Findings
Negative life events may lead to depression, neighborhood affects depression (Rich areas less likely to become depressed than poor areas), personality was not a factor
Methodological Considerations
Generalizability problems, very large sample, maybe demand characteristics
Ethical Considerations
Highly ethical, unanimity was kept
Conclusion
There are many environmental and life stressors that can lead to depression

Anorexia Nervosa

Biological:
Dispositional (genetic) factors, such as personality (perfectionism) may contribute to the disorder. Possible appetite and weight regulation imbalance in the hypothalamus, neurotransmitters (serotonin)

Mazzeo & Bulik (2009)
Aim
To investigate how genes and environment interact for eating disorders
Sample
Unknown
Procedure
Literature review of correlation studies
Findings
Several types of gene-environment-interactions contribute to eating disorders
A) Situational-Social environment, parents
B) Dispositional-Girls with high levels of perfectionism may have demands on themselves and to be more susceptible to media influence
Methodological Considerations
Considers more than one factor for the disorder, cause and effect is not clear
Conclusion
Several types of gene-environment-interactions contribute to eating disorders

Cognitive

Attentional biases and cognitive styles that distort reality/body image

Southgate (2008)
Aim: Investigate preferential information processing style in eating disorder (ED)
Participants: sixty nonmedicated female participants 26 with health diet, 20 with anorexia, and 14 with bulimia
Experiment: We compared the performance of participants with EDs against healthy controls in a task that measures cognitive style (reflection–impulsivity) and cognitive efficiency (inefficient–efficient).Sixty non-medicated female participants (healthy controls n=26, anorexia nervosa n=20, bulimia nervosa n=14) took part in the Matching Familiar Figures Test (MFFT), a difficult visual search paradigm with high response uncertainty. Participants with anorexia scored significantly higher on the efficiency dimension score than the control group. No significant differences were found across groups on the dimension ‘reflection–impulsivity’.
Finding: Participants with anorexia are more efficient (quicker response latencies in conjunction with fewer errors) in this visual search task that requires an analytic approach. This supports the hypothesis that individuals with anorexia have a positive bias toward local detail processing, indicative of weak central coherence.
Evaluation : Lack ecological validity because the investigation was conducted in a controlled lab and lacks generalizability because the experiment focus on only female patients with anorexia the result cannot be apply to males patient

Social cultural
Media exposure, social learning

Becker Study (1993-1995):
AIM: to investigate the influence of cultural factors on the incidence of anorexia nervosa by taking advantage of cultural change when television was first introduced to the island of Fiji to see what effects western TV would have on attitudes towards eating and the incidence of anorexia nervosa
PROCEDURE: In 1993 when TV was first introduced to the island of Fiji, 63 native Fijian girls were asked to complete a questionnaire on attitudes towards eating and were questioned about their TV viewing habits. 2/3 years later, a further sample of 65 girls aged 17 years on average were re-questioned to assess the impact of TV on their eating habits. Girls were also interviewed about their views on eating and television.
FINDING: % of girls who reported vomiting in order to control weight changed from 3% in 1993 to 15% in 1995. Girls with a high score on the eating questionnaire (indicating a risk of disordered eating) changed from 13% in 1993 to 29% in 1995
CONCLUSION: The findings indicate a strong link between exposure to western ideals of thinness and changed attitudes towards eating.
Such changed attitudes are likely to lead to the development of eating disorders such as anorexia nervosa
EVALUATION: The findings do not necessarily demonstrate a cause (Validity low). This was a natural experiment during which the investigators had no control over extraneous variables (Credibility low). Changed attitudes may not lead to eating disorders - we do not all show signs of eating disorders even if we are all exposed to the same cultural influences, there may well be a biological vulnerability. Low generalizability, as study was conducted in only country.

A list of Phobias!