Late Night Negative Thoughts Linked to Higher Levels of Depression
Individuals with depression often experience uncontrollable negative thoughts. This process, known as rumination, has been found to be a major symptom of depression. In a recent study, Keisuke Takano and Yoshihiko Tanno, of the Department of Cognitive and Behavioral Science, Graduate School of Arts and Sciences, The University of Tokyo, examined the types and frequency of thoughts occurring in 68 depressed college students to determine the relationship between rumination and depression. They said, “A large body of recent studies has focused on a persistent, chronic form of self-focus as a trigger for psychological illnesses. Depressive rumination, which is conceptualized as the tendency to repetitively focus on symptoms of distress and the possible causes and consequences of these symptoms, is known to be a serious risk factor for depression.”
Using the experience sampling method (ESM), the participants were instructed to record their moods and thoughts at several different points throughout the day when prompted electronically. Over the course of seven days, the participants reported whether they felt distressed, upset, nervous, afraid, scared or jittery. The researchers asked the participants to identify the aspects of their thinking if it was unpleasant, uncontrollable and focused on self.
They discovered that the participants who experienced higher levels of all three aspects of thinking also had the highest levels of depression. “These results suggest that the self-focused thinking of trait ruminators is likely to be more negatively valenced and perceived as more uncontrollable,” said the team. Additionally, they found that the participants with high levels of depression were more likely to ruminate in the evening. “A number of studies suggest that presleep cognitive arousal—such as worry and rumination—leads to insomnia or poor sleep quality.” They added, “Investigating the causes and consequences of evening rumination would provide important insights into the mechanisms involved in the maintenance and exacerbation of depressive symptoms.”
Reference:
Takano, K., & Tanno, Y. (2011, April 25). Diurnal Variation in Rumination. Emotion. Advance online publication. doi: 10.1037/a0022757