Abstract: Nolen-Hoeksema proposed a response style theory in 1987, which claimed that distraction would be more effective in alleviating a depressed mood than rumination. On the basis of this theory, a variety of studies have been conducted to investigate the effects of rumination and distraction. It is consistently suggested that rumination may lead individuals to recall more negative autobiographical memory and run into a kind of negative vicious circle, and then maintain and exacerbate depressed mood. However, the effects of rumination on physiological responses have been rarely discussed, and no significant differences between ruminating and distracting participants have been found so far. The present study investigated the effects of rumination and distraction on normal adults’ emotional subjective reports, physiological response and autobiographical memory when they were facing negative mood after emotion induction in laboratory. It was hypothesized that rumination would exacerbate ongoing negative mood and lead to more negative general autobiographical memories than distraction response according to previous studies.
Method
Seventy-two participants were recruited and 64 participants’ data were analyzed. During the experiment, participants were randomly divided into two groups. A dysphoric mood was induced in one half of them and a nondysphoric mood was induced in another half with stories and movie clips created by researchers. The participants were then randomly assigned to rumination and distraction tasks. Emotional subjective reports were filled in after adaptation phase of physiological device (BIOPAC MP150wsw), emotion induction and response style task. Physiological responses and autobiographical memory data were also collected. Repeated measures ANOVA and 2´2 factorial ANOVA were mainly used for data analysis after raw data transformation.
Results
The results showed that, after inducing dysphoric emotions in the laboratory and asking them to participate in the response style tasks, response style had no effects on participants’ negative emotion and physiological responses but rumination/negative group retrieved more negative general autobiographical memories, while distraction reduced general autobiographical memory. The results of negative emotion did not support the hypothesis but the results of autobiographical memories did. The physiological results were consistent with previous studies.
Conclusions
When negative mood was induced, rumination led individuals retrieve more negative moods, maintained general autobiographical memory and then likely exacerbated negative mood. This study extended Nolen-Hoeksema and many other researchers’ findings and supported Nolen-Hoeksema’s response style theory. Rumination seemed to have both positive and negative effects. When the participants’ dysphoric emotions were induced in the laboratory, which was unstable, and didn’t meet the clinical criterion, the analytical and evaluative thinking component of rumination would function dominantly and improve participants’ negative moods. The components of rumination should be examined in future studies.

Key words: rumination, distraction, autobiographical memory, negative mood