Cognitive Theory of Depression

Cognitive theories of depression is "cognitive" because they address mental events such as thinking and feeling. Cognitive theory suggests that depression results from maladaptive, faulty, or irrational cognitions taking the form of distorted thoughts and judgements. Depressive cognitions can be learned observationally as is the case when children in a dysfunctional family watch their parents fail to successfully cope with stressful experiences or traumatic events.

According to cognitive behavioral theory, depressed people think differently than non-depressed people, and it is the difference in thinking that causes them to become depressed. For example, depressed people tend to view themselves, their environment, and the future in a negative way. As a result, depressed people tend to think negatively and blame themselves for any misfortune that occurs.

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Environmental Theory of Depression

The environment has a lot of influence if you are depressed. Environmental factors are also called emotional factors, and can result from stressful emotional situations, such as a lack of loving parents or the death of a parent during childhood. To make it even more complicated, depression can also occur as a result of a combination of these factors mentioned.

If you inherited vulnerability to depression from one of your parents, your brain may react to a stressful event in a way that causes you to get depressed. Certain environmental situations, such as stress or breakup of important attachments, also may precipitate depression, especially in weak or vulnerable people.

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Biological Theory of Depression

Medical Research has contributed alot to our knowledge about depression, however scientists do not know what is the exact cause of a depressive illness. Most probably there is no factor that gives this illness, but doctors are trying to put this puzzle together. Doctors believed that the causes of depression were thoughts or emotions troubling a person, but research has concluded that three main factors that cause depression are: biological, genetic, and environmental.
People suffering from depression have an imbalance of neurotransmitters, which are natural substances that allow brain cells to communicate with one another. Two transmitters implicated in depression are serotonin and norepinephrine. Other chemicals may be altered in depressed people, such as cortisol, which is a hormone that the body produces in response to stress, anger, or fear. Cortisol never lowers in depressed people, therefore they always feel these emotions.http://www.healthyplace.com/depression/main/causes-of-depression/menu-id-943/