Most people have changes in mood from time to time, sometimes feeling happy and sometimes feeling down. The change in mood that signifies depression is of a different degree, a lowering of mood that is oppressive and tends to effect most aspects of life.
Depression can vary in severity from mild to very severe. The most prominent symptom is a low mood that may be ‘feeling low’ in mild depression, to feeling unremitting, crushing despair and misery in severe depression. Severe depression causes activities that usually bring pleasure to feel flat and meaningless and the person feels hopeless about themselves and their future. Other symptoms of depression that are common, and also present in varying degrees of severity, include loss of concentration, loss of appetite, loss of libido and difficulty sleeping.
Sometimes there is a clear and understandable reason why someone may be depressed, for example, experiencing loss of some kind is a common precursor to low mood. At other times though, the depression may seem ‘to come out of the blue’ with no obvious cause.
Antidepressant medication is commonly prescribed for depression by GPs and psychiatrists, and indeed is particularly indicated for people with more severe symptoms and for those for whom the depression seems to ‘come out of the blue’. However, many people have an inkling of why they are depressed and prefer to deal with it by using psychological therapy of one type or another, or by combining it with medication. Choosing a psychological therapy may be more painful in the short term as it often means facing up to difficult and painful things, but if successful it is also more likely to last as a treatment and to make recurrence of the depression less likely.
From a CBT perspective, therapy focuses on the maintenance cycle of depression. As stated earlier, depression causes people to feel bad about themselves and gloomy about their future and the world. This can lead to social withdrawal which leads to isolation, thus perpetuating the low mood and poor sense of self. Lack of motivation is also part of depression, so usual tasks don’t get done. There is then a burden of a backlog of these tasks with repercussions that feed into the depression cycle. Depression causes us to ruminate on real or perceived failures in the past and the present which again lowers the mood further. Some people may turn to comfort through overeating, drinking too much alcohol or using drugs, and these usually lead to regret and contribute to the depression cycle. There are other aspects to the maintenance of depression but I hope this gives you some idea. CBT aims to reverse these maintenance cycles to lift the depression. A CBT approach would usually begin in this way and then address possible underlying issues after that.