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Understanding Depression


Causes of Depression
Research has shown that depression can stem from an imbalance of neurotransmitters in the brain.
Research has shown that depression can stem from an imbalance of neurotransmitters in the brain.
©2006 Publications International, Ltd.

Depression may be related to many factors, including a family history of depression, medical illnesses, alcohol, drugs, gender, and age. Additionally, an individual's self-confidence, personality traits -- such as dependency on others or perfectionism -- and unrealistic expectations may lead to depression. Stressful events, such as death of a spouse or loss of a job, also contribute to depression. Many people with major depression also suffer from intense anxiety.

Theories of Depression

There are many theories about the causes of depression. The social learning theory suggests that lack of positive reinforcement from others may lead to negative self-evaluation and a poor outlook for the future. The psychoanalytic theory suggests that a significant loss (such as of a parent) or a withdrawal of affection in childhood (whether real or perceived) may lead to depression in later life. Interpersonal theory emphasizes the importance of social connections for good mental health. Other theories suggest that unrealistic expectations of oneself and others and loss of self-esteem are essential components leading to depression.

Some individuals may be biologically predisposed to depression; in other words, they may have been born with a tendency to develop depression. Researchers continue to investigate chemical reactions in the body that are controlled by these genes. Depression often runs in families. For example, if one identical twin suffers from depression or manic-depression, the other twin has a 70 percent chance of also having the illness.

Research indicates that some people suffering from depression have imbalances of neurotransmitters (natural body chemicals that enable brain cells to send messages to the rest of your body). Biochemicals that often are out of balance in depressed people are serotonin, norepinephrine, and dopamine. Several neurotransmitter imbalances may be involved; researchers are seeking other neurotransmitters that may be important in clinical depression.

Environmental Influences

Researchers view depression as the result of interaction between environmental and biological factors. Depression can be endogenous (internally caused) or exogenous (related to outside events). Major changes in one's environment, such as a move or job change, or any major loss, such as a divorce or death of a loved one, can bring on depression. Feeling depressed in response to these changes is normal, but when it becomes a severe long-term condition (longer than one month) and interferes with effective functioning, it requires treatment.

Some environmental factors relating to depression include being unemployed, poor, elderly, or alone. Depression changes one's way of looking at ordinary life circumstances. A depressed person tends to exaggerate negative aspects, which leads to feelings of hopelessness, helplessness, and being overwhelmed.

Debilitating diseases can severely restrict usual life-style, resulting in depression. Illnesses that affect brain functioning and impair blood flow to the brain can produce depression. Such illnesses may include malfunctions of the thyroid or parathyroid gland, diseases that affect the nerves, nutritional disorders, and infectious diseases. Depression can also occur as a side effect of certain medications.

Unhappy feelings aren't necessarily bad. In fact, some are downright healthy. For example, when someone you care about dies, mourning is a healthy form of sadness, a natural reaction to loss. Over time (sometimes a year or more), these feelings of grieving progress from bad to better.

The "downs" most people feel from the normal stresses of life usually last a few days to a week, and then resolve. In depression, however, a person often becomes stuck in the blues. There is no progression of feelings. Emotions become trapped in a repeating loop. If you feel depressed for more than a couple of weeks or if your depression interferes with your daily life, you should seek professional assistance.

After reading about the causes of depression, perhaps you suspect you or someone you know could be suffering from the condition. In the next section, we will show the symptoms of depression that you should look for.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.