The cognitive approach argues that patterns of thinking are responsible for our mental disorders. One theory is that rumination - that is, the focused attention on the symptoms of one's distress. This is the basis of Nolen-Hoeksema's Response Styles Theory.

Why do the researchers believe that rumination may play a key role in depression? There are two components to rumination.  First, the individual focuses on the symptoms of distress.  Often they will say, " I just can’t concentrate."  They also worry about the meaning of their distress, thinking, "Will I ever get better? Am I a bad parent?"

Nolen-Hoeksema has found that ruminators are more uncertain about solutions they come up with to their problems than non-ruminators.  This uncertainty may keep ruminators analyzing everything that happens to them or over-interpreting what others say.

In line with Beck's theory of depression, rumination contributes to feelings of hopelessness about the future and a negative evaluations of one's self.  Ruminators vacillate between anxiety and depression - that is, uncertainty and hopelessness.

The researchers argue that rumination may prolong negative thinking associated with depressed mood, interfere with good problem solving, and cause friction with friends and family.

The aim of the research was to carry out a prospective study of the role of rumination on symptoms related to depression.

The researchers had a sample of 1132 participants that had been randomly selected from a community sample of adults in the San Francisco area, including San Jose and Oakland.  They were chosen by random-digit dialing of telephone numbers. 

The participants were interviewed two times over a period of one year. All of the participants were interviewed in person in their own homes.  The interview consisted of a clinical interview which lasted for 90 minutes. This included a battery of tests which included the Beck Depression Inventory, the Hamilton Rating Scale for depression, the SCID, and the Beck Anxiety Inventory.

Finally, they were given a rumination and coping questionnaire, designed by the researchers. For example, on the questionnaire they were asked to rate how often they think, “Why do I react this way”, “I think about how sad I am”, or “I think that I will lose my job if I don’t get better.”

Participants who showed signs of Major Depressive Disorder at the time of the first interview had a significantly higher score on ruminative responses than those who did not show signs of MDD. Participants who had never been depressed had significantly lower rumination scores than the other participants.  In addition, those who had been depressed but improved had lower rumination scores than those who remained chronically depressed.

The research supports Beck's theory that patterns of cognition can have a negative effect on mental health.

The Response Styles Theory is supported by biological evidence - such as Farb (2011), see below.

The study relied on self-report questionnaires as well as diagnosis through clinical interviews.

Originally there were 1317 participants.  Although there was a small attrition rate, it was those with the strongest symptoms that dropped out – which means that there may have been a bias introduced into the study

No information was available on whether the participants living with depression were receiving treatment or how other protective factors may help them to cope with their disorder. The results may have been influenced by uncontrolled confounding variables.

Farb et al (2011) showed 16 formerly depressed patients sad and neutral movie clips and tracked their brain activity using a fMRI. They compared this to 16 healthy controls.  Both groups underwent functional magnetic resonance imaging (fMRI) while viewing sad and neutral film clips. The researchers calculated correlations between emotional reactivity (neural responses to sad vs. neutral film) in patients after the scanning and subsequent relapse status over an 18 month follow-up period. The prediction was that activity in the medial prefrontal cortex predicted relapse. The prefrontal cortex is the region of the brain that is most active when people ruminate.

The results supported the hypothesis: ten of the 16 patients had relapsed into depression during the 18-month follow-up period. Faced with sadness, the relapsing patients showed more activity in the prefrontal cortex. These responses were also linked to higher levels of self-reported rumination. On the other hand, the healthy participants showed activity in the visual cortex.