Abnormal psychology studies what a "normal" or properly socialized person would consider unusual. The definition of normal is determined by what the greatest number of people, or the majority, do, say, feel, act out and think. There is both a psychological and a biological approach to diagnosing and treating depression. Many psychologists will choose one or the other, while some treat both. Psychology students, however, will have to study all possible causes and treatments for depression.
To study depression from a biological perspective is to assume that a person's internal chemistry plays a significant role in the likelihood that they will get depression, respond well to treatment and recover. Neurochemistry studies look to chemical imbalances that are genetic or hereditary, such as low levels of serotonin or norepinephrine, as the cause of depression.
Besides being chemically rooted, depression is thought to be the effect of incomplete or faulty psychological development. This type of hypothesis is socially based, and states that a person's very early experiences in the world can forcefully affect the way they see, think about and act in the world later on in life. An example of a traumatic experience that may cause depression later in life is the death of a parent. Whether or not teachers or caregivers can sense a child's depression at the time of this event, it is possible this child may grow up and find it difficult to engage in meaningful, trusting relationships. If depression is psychosocial, it is the result of past emotions that were suppressed, turned inward or never dealt with properly.
To understand depression, it is important to look at the occurrence of depression worldwide. Where does depression occur most frequently? In what age range, gender or socioeconomic status does depression occur the most? Abnormal behavior can be defined as a behavior that occurs in a very low percentage of the population, and is therefore deviant, illogical, risky or potentially dangerous. However, just because a certain behavior occurs in a low percentage of the population does not make it automatically abnormal or dangerous.
Recognizing symptoms of depression is important for diagnosis. A student of psychology will have to learn to identify depression by common symptoms such as increase or decrease in appetite and amount of sleep, low energy, loss of interest in daily activities, inability to concentrate and manic episodes, among others.
A student must fully understand the theories of well-known psychologists that came before him. Ferster, Freud, Lazarus, Lewinsohn and Beck are some well-known psychologists whose theories contribute to a broader understanding of the possibilities in recognizing and treating depression. Memories, positive and negative reinforcement, stimuli and reactions to stimuli are a few of the important topics these theorists cover.
A psychologist must know what treatments are available and how they work in order to decide which he should use for each individual client. One can choose to use medical treatments, such as antidepressants and antipsychotics like Prozac, and/or psychological or cognitive behavioral therapies, which are one-on-one sessions between a client and a therapist. There are several methods of psychological therapy, all of which involve the exploration of the client's thoughts and feelings guided by a trained psychologist. Reading self-help books, practicing exercises at home and attending support groups can be effective for treating depression.