Abnormal psychology

Abnormal psychology is a sub-discipline of psychology which seeks to describe, predict, explain, and change abnormal patterns of behaviour.

Defining Abnormality

Abnormality means a deviation from the norm. There is no single, simple definition of abnormality due to the complexities of human behavior. However, there are four main definitions which can broadly explain abnormal behavior.

The first definition is norm violation. This view of abnormality views humans in the context of their [culture]. Each culture has a set of rules that define right and wrong, which are called norms. These norms guide many aspects of a person's existence, and can widely differ from one culture to another. For example, it is polite in Arab countries for men to stand close together and maintain eye contact during conversation. This would be probably be unsettling to people raised in a Western society. The second definition is statistical rarity. Abnormality is calculated as a substantial deviation from the population average. Those people who are statistically rare are considered abnormal. For example, a person who washes their hands for several hours each day. The third definition is maladaptive behavior. People are expected to meet the demands of everyday life, and not engage in harmful behavior. If a person cannot pay their bills, hold down a job, or socialize with friends or family, then their behavior could be considered maladaptive. This is a practical definition or managing life successfully, and it takes a person's lifestyle into consideration. The fourth definition is personal discomfort, when a person is distressed over their own thoughts, feelings, or behaviors. People who are content with their lives do not seek out treatment from a mental health professional. This definition relies on a person's judgment, rather than that of their culture or diagnostician.

Maher and Maher (1985) describe four categories of abnormal behavior:

• Harmful behavior to self or others
• Poor contact with reality
• Emotional reactions unsuitable to the situation
• Erratic, unpredictable behavior

History

Early views of abnormal behavior were explained by remote and supernatural forces, or as a battle between good and evil. Possession by evil spirits was treated by exorcism or trephination. Exorcisms were performed to make the body uncomfortable for an evil spirit to inhabit. These commonly included prayer, noisemaking, and special potions, although some possessed people were submerged in water, whipped, or starved. Trephination is a form of surgery in which a hole is drilled in the skull. This was performed because it was believed inhabiting spirits caused abnormality, and by creating holes it would release the spirits.

A major breakthrough occurred in 1897 when Krafft-Ebing made the discovery that general paresis was caused by syphilis. This was the first mental disorder found to have a biological cause, and advanced the medical model of psychopathology.

Perspectives

• Behavioral psychology - this school of thought views behaviour as the result of interaction with the environment. Abnormal behaviour is seen as the result of causes or circumstances in the environment. Much of this field is based on classical and operant conditioning.

• Cognitive psychology - this school of thought has a strong focus on understanding the mechanisms of the mind in order to explain behavior. This perspectives views abnormal behaviour as the product of mental processing.

• Neuroscience - this perspectives seeks to understand abnormality by studying the neurological bases of behaviour. It focuses on the interaction between behaviour and biological functions.

Classification

Mental health professionals classify mental disorders with by category. The use of labels allows communication between clinicians. Labels are valuable for statistical purposes in research, and for bridging the gap between research and treatment. Categories contribute to planning of treatment programs and facilities.

The use of classification has not gone without controversy for several reasons. Labels of mental illness carry social stigma. The current diagnostic categories are imperfect since mental disorders rarely conform to exactly one label and may overlap. A different system of dimensional classification has been presented as an alternative. This is based on dimensions of pathology, for example, a person would have several ratings of severity scales such as depression, anxiety, and obsessions.

In North America, the main diagnostic text is the Diagnostic and Statistical Manual of the American Psychiatric Association. The current version of the handbook is known as the DSM IV-TR. It lists a categories of disorders and provides a detailed description of each one. It also gives general descriptions of incidence, prevalence, and duration. The diagnostic process uses five dimensions called 'axes' to ascertain symptoms and overall functioning of the individual.

Internationally, the system for the classification of mental disorders is the 10th edition of the International Classification of Diseases (ICD-10). The ICD-10 has been used by WHO Member States since 1994. Chapter five covers about 300 mental and behavioral disorders, and forms the basis of the APA's DSM-IV-TR. The ICD-10 is available Online.