Cognitive Theory of Depression

Aaron Beck argues that people become depressed simply because their thinking is biased, always siding with the negative interpretation of situations, even if it is not the correct idea. According to his theory, people acquire a negative idea of the world during their childhood or adolescence due to stressful life situations.
When the person with these ideologies encounters a situation that slightly resembles the conditions of the original setting, said schema is activated. He proposed that depressed beings usually share the same biases: arbitrary inference, selective abstraction, over-generalization, magnification and minimization. These are used as quick ways to generalize and make negative inferences about one self, such as “I can never do a good job,” “Nothing is ever going to be alright.”

SOURCE:
http://www.personalityresearch.org/papers/allen.html
http://www.mrc-cbu.cam.ac.uk/research/emotion/cemhp/images/depression.jpg
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