Ill-judged commentary on poor mental health often makes it sound like biological causes are somehow more fundamental and important than social or psychological factors. This is the allure of reductionism. In fact all levels of explanation need to be considered, and it may be that psychological factors are the most amenable to intervention.
A new study led by chartered clinical psychologist Peter Kinderman at the University of Liverpool supports this perspective. Working with the BBC, he and his colleagues conducted an online survey of over 32,000 people (aged 18 to 85), collecting data on their mental health (in terms of depression and anxiety), their genetic risk factors (as measured by their family history), their relationships, life events, demographics, and two aspects of their psychological tendencies: rumination and attributional style. The first of these refers to how much people worry and dwell on things, the second with whether they blame themselves or external events when things go wrong.
Kinderman's team used a sophisticated statistical technique called structural equation modelling to investigate the relations between these different biological, social and psychological factors and mental health. Their analysis suggested that traumatic life events have the strongest direct link with depression and anxiety, followed by a family history of mental health problems and low social status (in terms of education and income). Loneliness and lack of social support were also linked directly with poor mental health.
Arguably the most important finding, however, is that the links between these factors and poor mental health were significantly (though not fully) mediated by the psychological measures of rumination and attributional style. "Our results clearly support the contention that biological, social, and circumstantial causal agents affect our mental health and well-being through their impact on how we process information and perceive the world," the researchers said.
The findings support a model that looks like this:
Although in this study psychological processes didn't fully mediate the relationship between the factors on the left and mental disorder, this could well be because only two forms of psychological process were measured.
The results have practical implications, the researchers said, because psychological processes like rumination and self-blame are readily amenable to talking therapies. These results are also timely because they appear to complement the ambitious Research Domain Criteria (RDoC) project of the National Institutes of Mental Health in the US. That project seeks to identify the biological factors that are linked with psychological and cognitive features that cut across existing diagnostic categories. Stated differently in terms of this new study, that could mean investigating the precise biological risk factors that give rise to psychological processes such as excessive rumination, which in turn can manifest in diverse clinical symptoms.
Of course this study has limitations, as acknowledged by the researchers. Foremost is that the data only represent a single snap-shot in time. For a more robust test of the proposed mediating role of psychological processes it will be necessary to collect data from participants over many months or years.
Kinderman P, Schwannauer M, Pontin E, and Tai S (2013). Psychological processes mediate the impact of familial risk, social circumstances and life events on mental health. PloS one, 8 (10) PMID: 24146890
Peter Kinderman discusses his new findings on his personal blog.
Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.