Cognitive Behavioural Therapy (CBT) and Depression (Thinking Errors)

The basic tenet of Cognitive Behavioural Therapy, or CBT, is that what you think affects the way you feel. That is to say, if you think depressive thoughts then you will feel depressed. Conversely, if you manage to stop yourself thinking these thoughts, then your depression will lift.

As a psychiatrist using CBT techniques, my first step is to look for unhelpful patterns of thinking with my clients. Depressed people often think in particular ways that are very different from non-depressed people. These ways of thinking are called - in CBT language - "thinking errors". Thinking errors help to cause and then maintain depression.

Numerous different thinking errors have been identified by CBT therapists over the years, and particular kinds of errors seem to predispose to particular psychological problems. In my experience as a therapist, the most common errors found in depression are "All-or-Nothing" thinking, "Mental Filtering", "Disqualifying the Positive", and "Personalising".

"All-or-Nothing" thinking (also known in CBT circles as "Black-or-White" thinking) emphasises extremes and ignores the fact that most things in life are shades of grey rather than absolutes. For example, a person thinking in this way may play one poor game of tennis and then decide that he's totally useless and give up forever. Or she may miss one yoga class and tell herself that as she's fallen behind, there's no point in going back. "All-or-Nothing" thinking sets very rigid rules for a person to live by - rules that, if broken (as they almost inevitably are!) can lead to the abandonment of enjoyable and worthwhile activities, and predispose the person to depression.

"Mental Filtering" is the term applied to the thinking patterns of people who "see" the world in a depressive way. People with this thinking error are biased in what they take notice of, and what they later remember. They will tend to notice (or, in CBT parlance, "attend") to objects, people, or events that "fit-in" or confirm their previously held beliefs. For example, a depressed person who thinks that the world is an unpleasant place to live is more likely to remember the sad news stories as compared to a non-depressed person. A depressed person who thinks that they're unlikeable will take extra notice of possible sleights from others. CBT theory posits that such mental filtering reinforces a person's depression.

A closely related thinking error is termed "Disqualifying the Positive". As well as focusing on the negative features of the world (and themselves), depressed people will often actively ignore (or "disqualify") evidence to the contrary. A depressed person may well recall the person at the party who ignored them, but he will forget or downplay the others who chatted to him for hours. If a CBT therapist asked them about this, he will often say things like "oh, they just felt sorry for me", thereby turning a positive interaction into something very different.

"Personalising" is the term given to a type of thinking that places the person at the centre of events. Such a view of the universe places a huge burden on the persons shoulders - they can feel responsible for all the bad things that happen. You may be "Personalising" when you feel guilty about not being able to help an unemployed friend keep his house, or when reading about climate change due to our Western way of living. There are factors beyond your control and for which you should not take responsibility. If you do, then CBT hypothesises that you will experience feelings of guilt, shame, and ultimately depression.

The above is a brief review of the common thinking errors that I have come across during the course of my work as a therapist in Edinburgh. Identifying such errors with the client is a first step on the way to identifying other, healthier, ways of thinking.

Dr Steve Last is a Psychiatrist who uses CBT techniques. He is based in Edinburgh. Please visit http://www.drstevelast.co.uk for further information on psychological problems and CBT.