In this study by Strange and colleagues, they found that inflexible cognition predicted the onset of depression in adolescence.
Based on the results of their study, the researchers suggested that both higher levels of rumination (compulsive attention to negative symptoms, and their possible causes and consequences) and poorer attentional shifting abilities were predictive of a shorter time to first onset (beginning) of major depression among a community sample of adolescents. Consistent with prior research, sex differences emerged: girls were twice as likely as boys to experience first onset of depression during the course of the study. However, the effects of rumination in predicting episode onset were specific to boys. Rumination and attentional shifting abilities acted as independent predictors; contrary to hypotheses, these were not correlated, and attentional shifting did not moderate (or influence) the relationship between rumination and depression onset. These results provide evidence that rumination and attention shifting may be important independent factors in the development of mood disorders in adolescence.
Jonathan P. Stange, Samantha L. Connolly, Taylor A. Burke, Jessica L. Hamilton, Elissa J. Hamlat, Lyn Y. Abramson and Lauren B. Alloy
Temple University and University of Wisconsin, United States
The researchers sought to extend the existing research literature by evaluating attentional shifting and rumination as prospective, or long term, predictors of depression onset among never-depressed adolescents. They also evaluated sex differences in the relationship between attentional shifting and rumination and depression onset.
The researchers indicated that in a prior study of adolescents, attentional shifting and rumination were independently associated cross-sectionally (comparing two different samples typically at two different age groups/developmental stages) with current depression status. However, cross-sectional and case-controlled designs (when comparing depressed and healthy individuals) are unable to determine whether characteristics are true risk factors for the onset of the disorder, or whether they simply related to existing psychopathology. Although previous studies had indicated that rumination predicts the onset of depressive episodes in children and adolescents, the researches noted that no studies to date had evaluated both attentional shifting and rumination as simultaneous and potentially synergistic (interacting) predictors of the first onset of major depression. Finally, they stated that no prior studies had evaluated attentional shifting deficits as a predictor of the first onset of depression in adolescence.
The researchers decided to also investigate sex differences as past research had found that girls develop a more ruminative response style and higher rates of depression than boys by mid-adolescence. However, the literature had only provided mixed evidence about the presence of sex differences in the relationship between rumination and depression during adolescence, and they researchers noted that no studies had evaluated sex differences in the relationship between attentional shifting and first onset of major depression.
The researchers tested 341 adolescents and mothers who completed the baseline assessment and at least one annual follow-up assessment. The adolescents were diverse in terms of race, sex, and socioeconomic status. Participants in the current study were followed for up to almost 5 years and completed an average of about 2 annual follow-up assessments. They completed measures of depressive symptoms, rumination, and attentional shifting, and completed diagnostic interviews for depression.
ScientiFix tip: The researchers suggested that there were several limitations in their study. Of interest, they noted that adolescents in their sample had better attentional shifting scores and may have come from higher socioeconomic status households, perhaps limiting the generalisability of their results somewhat to adolescents with similar characteristics. Testing a larger, more diverse sample of adolescents would have allowed to researchers to suggest these results are apply more broadly to more adolescents. They also remarked that while they evaluated time until the first onset of depression, they did not evaluate predictors of the severity or duration of first depressive episodes. Understanding these predictors would additionally allow doctors and clinicians to better treat and understand adolescent depression.