Why is cognitive ability associated with psychological distress and wellbeing? Exploring psychological, biological, and social mechanisms

This study examined whether associations between cognitive ability and mental health (depression, anxiety, and psychological wellbeing) could be accounted for by different categories of risk factors: socioeconomic status, engagement in pleasant activities, coping/appraisal, social relationships, biological risk factors (inflammation, cortisol, heart-rate variability), and reaction time. Participants were from the Midlife in the United States study (n = 1744; mean age = 54, range 25 to 84). Adjusting for social relationships, biological risk factors, or reaction time had almost no influence on the association between cognitive ability and mental health. Adjusting for engagement in pleasant activities attenuated the associations with depression and anxiety by one-fourth; adjusting for coping/appraisal by one-third; and adjusting for socioeconomic status by one-fifth. These attenuations were larger for the associations with positive affect and life satisfaction. These findings suggest that the association between cognitive ability and mental health may be partly explained by cognitive-behavioral mechanisms and the protective influence of socioeconomic status.