Douglas Marchant and Dr. Claudia Clayton, Psychology
Rumination can be defined as persistent, recyclic thinking (Rippere, 1977). There are characteristic differences between normal rumination, which is simply recyclic thinking, and depressive rumination, which is characterized by recyclic thoughts focused on one’s depressive symptoms and the ramifications of those symptoms (Nolen-Hoeksema, 1991). Therefore, depressive rumination is narrower in its content than normal rumination. Examples include revisiting private regrets and disappointments, focusing on feelings of loneliness, and dwelling on personal inadequacies (Davis & Nolen-Hoeksema, 2000). The following three examples of depressive rumination are characteristically different in focus than the depressive thoughts given above: “Why am I so sad?”, “Why can’t I concentrate?”, and “Why can’t I cope better?” The first three examples were thoughts describing the individual’s depressive symptoms, whereas these latter three thoughts are focused on the etiology, maintenance, and course of those depressive symptoms (Lyubomirsky & Nolen-Hoeksema, 1993).
In addition to knowing what depressive rumination is, researchers have tried to understand why it is that some people ruminate depressively. It is believed by some researchers that individuals ruminate because they think they might gain insight into the etiology of their depressed mood (Papageorgiou & Wells, 2001). They continue ruminating under the assumption that if they focus inward, they can analyze their feelings and perhaps find solutions that will relieve their depression (Lyubomirsky & Nolen-Hoeksema, 1993; Papageorgiou & Wells, 2001, 2004; Watkins & Baracaia, 2001). Contrary to this assumption, researchers have demonstrated over the past twenty years that ruminative responses to a depressed mood produce longer and more severe periods of depression (Lyubomirsky & Nolen-Hoeksema, 1993; Morrow & Nolen-Hoeksema, 1990; Nolen-Hoeksema & Morrow, 1993; Robinson & Alloy, 2003).
One reason why rumination about depressed mood extends and increases this mood is because rumination negatively biases a person’s thinking. This negatively-biased thinking produces distorted interpretations of memories and current life events, negative self-evaluations, feelings of hopelessness to control one’s life, pessimistic attributions for interpersonal problems, and dismal expectations of the future (Lyubomirsky & Nolen-Hoeksema, 1995; Lyubomirsky, Caldwell, & Nolen-Hoeksema, 1998). Negatively-biased thinking hinders daily functioning; it is not just an impediment within the mind. People responding to depressive moods by ruminating may find it difficult to concentrate on other obligations. In fact, research has found that rumination impairs concentration on several academic tasks, indicating that rumination could adversely affect social or business tasks (Lyubomirsky, Kasri, & Zehm, 2003). Also, several studies have shown that people who ruminate produce ineffective problem-solving strategies (Lyubomirsky & Nolen-Hoeksema, 1995; Strack, Blaney, Ganellen, & Coyne, 1985) and show less motivation and commitment to carry out fine solutions to their problems (Lyubomirsky, Tucker, Caldwell, & Berg, 1999; Ward, Lyubomirsky, Sousa, & Nolen-Hoeksema, 2003). Thus with a loss of concentration, less-effective problem-solving, and lack of motivation and commitment a person could have difficulty handling day to day tasks.
These consequences associated with depressive rumination have been demonstrated in research dealing mostly with cognitive and daily functioning. However, there has been very little research concentrating on the physiological effects of depressive rumination. One lone study by Vickers and Vogeltanz-Holm (2003) placed nondysphoric subjects in rumination or a distraction task, then measured their mood and physiological responses. The study found that self-reported depressed mood increased in the rumination condition. However, differences in heart rate and diastolic blood pressure were not significant. This insignificant result brought Vickters and Vogeltanz-Holm (2003) to suggest that more studies need to be performed investigating rumination and its physiological responses.
In our study we are responding to this suggestion by investigating the physiological response, specifically heart rate, in individuals who consistently do and do not ruminate by administering laboratory induced stress. We are still in the process of data collection. In addition to studying physiological response, our study differs from previous research in its methodology. To illustrate, the rumination and distraction condition used by Vickters and Vogeltanz-Holm is common in rumination studies. These studies have consistently found that subjects in the distraction condition perform better, are more motivated, and report better mood and less worry. But, these rumination studies all induced a ruminative condition to affect the dependent variable. There have been no studies investigating people who consistently ruminate (who can be distinguished by high scores on a self report rumination survey) during a time when they are not ruminating.
In contrast to inducing rumination, we will compare individuals who consistently ruminate to individuals who do not. We propose that an individual who scores high on the rumination survey will consistently ruminate across many situations. In support of our assertion that these individuals consistently ruminate, one study reported that 83% of participants showed consistent response style to depressed moods (either distraction or rumination). This response was found consistent through daily self-report over a period of 30 consecutive days (Nolen-Hoeksema, Morrow, & Fredrickson, 1993). This datum suggests that response styles to depressed moods are consistent to the individual, regardless of situation. In our study neither the consistent ruminator nor the non-ruminator will be in a state of rumination during the experiment. We will compare the differences in physiological response to two stressors given to people who consistently ruminate and people who do not. This will demonstrate whether or not people that consistently ruminate experience a stronger response to stressors than non-ruminating people. We hypothesize that participants with a higher tendency towards rumination will experience a greater increase in heart rate during and immediately following completion of an arithmetic test and a public speaking exercise.