Emotion 2008, Vol. 8, No. 2, 302–306
In the public domain DOI: 10.1037/1528-3542.8.2.302
Expressive Writing Buffers Against Maladaptive Rumination Denise M. Sloan and Brian P. Marx
Eva M. Epstein and Jennifer L. Dobbs
VA Boston Healthcare System and Boston University
Temple University
This study examined whether ruminative style moderated the effects of expressive writing. Sixty-nine participants were assessed for ruminative style and depression symptoms at the beginning of their 1st college semester. Participants were then randomized to either an expressive writing or a control writing condition. Changes in depression symptoms were assessed 2, 4, and 6 months later. Results showed that a brooding ruminative style moderated the effects of expressive writing such that among those assigned to the expressive writing condition, individuals with greater brooding scores reported significantly fewer depression symptoms at all of the follow-up assessments relative to individuals with lower brooding scores. In contrast, reflective pondering ruminative style did not moderate the effects of expressive writing on depression symptoms. These findings suggest that expressive writing could be used as a means of reducing depression symptoms among those with a maladaptive ruminative tendency to brood. Keywords: rumination, brooding, reflective pondering, depression, expressive writing
Dkane, & Gotlib, 2006). Thus, brooding is considered to be a maladaptive ruminative style, whereas reflective pondering is believed to be a more adaptive ruminative style. In light of these findings, Nolen-Hoeksema et al. (in press) proposed that intervention techniques that challenge irrational and hopeless thoughts, encourage the confrontation of painful images and emotions, and promote active problem solving may effectively ameliorate psychological and behavioral difficulties among those with a tendency to brood. One such technique that has the potential to aide brooders is the expressive writing procedure pioneered by Pennebaker and colleagues (e.g., Pennebaker, 1997; Pennebaker & Beall, 1986). The expressive writing procedure has been shown to positively affect the physical and psychological health of individuals diagnosed with cancer (Stanton et al., 2002), asthma or arthritis (Smyth, Stone, Hurewitz, & Kaell, 1999), fibromyalgia (Broderick, Junghaenel, & Schwartz, 2005), and chronic pain (Norman, Lumley, Dooley, & Diamond, 2004) and trauma survivors (e.g., Sloan & Marx, 2004) and college students (e.g., Epstein, Sloan, & Marx, 2005; Park & Blumberg, 2002). Expressive writing may provide opportunities to restructure maladaptive cognitions and confront negative thoughts and feelings about a particular negative or stressful experience. It may also facilitate active problem solving among brooders by having them actively analyze and process their experiences. Indeed, Lyubomirsky, Sousa, and Dickerhoof (2006) found that writing about stressful experiences was more beneficial than merely thinking about them. These investigators speculated that writing about stressful experiences is associated with greater benefits because it allows people to organize their experiences. In contrast, they speculated that thinking about stressful experiences is detrimental because it can rapidly transform into a repetitive cognitive process similar to brooding. In this study, we examined the extent to which brooding and reflective pondering moderated the effects of expressive writing on depression symptoms among beginning college students. We selected this group of individuals because transition to college is generally regarded as a stressful period for most young adults, and other studies have indicated that expressive writing may be helpful
Rumination is defined as a mode of coping with distress in which the individual repeatedly and passively focuses on distress and its possible causes and consequences (Nolen-Hoeksema, 1998; Nolen-Hoeksema, Wisco, & Lyubomirsky, in press). It is regarded as a stable response tendency that exacerbates further negative thinking, increases negative emotions, and interferes with effective problem solving (see Nolen-Hoeksema et al., in press, for a review). Ruminators also tend to display cognitive inflexibility (Davis & Nolen-Hoeksema, 2000; Ward, Lyubomirsky, Sousa, & Nolen-Hoeksema, 2003). Numerous studies have found that rumination increases the risk for depression (see Nolen-Hoeksema et al., in press). More recently, researchers have identified two ruminative styles, brooding and reflective pondering (Nolen-Hoeksema et al., in press; Treynor, Gonzalez, & Nolen-Hoeksema, 2003). In brooding, the cognitive focus is on the abstract (“What have I done to deserve this?”) and on obstacles that prevent one from overcoming problems, facilitating the belief that the situation is hopeless. In contrast, reflective pondering denotes a process by which the individual purposely turns inward to engage in adaptive problem solving. Treynor et al. (2003) showed that reflective pondering is associated with less depression over time, whereas brooding is associated with greater depression over time. In addition, brooding is associated with a greater history of depression and greater attentional biases toward negative stimuli (i.e., negative memory) relative to reflective pondering (Joormann, 2006; Joormann,
Denise M. Sloan and Brian P. Marx, National Center for PTSD, Behavioral Science Division, VA Boston Health Care System, Boston, Massachusetts, and Psychiatry Department, Boston University; Eva M. Epstein and Jennifer L. Dobbs, Department of Psychology, Temple University. This study was supported by a National Institute of Mental Health Grant R03MH068223 awarded to Denise M. Sloan. Correspondence concerning this article should be addressed to Denise M. Sloan, National Center for PTSD, Behavioral Science Division, VA Boston Healthcare System, Boston, MA 02130. E-mail: denise
[email protected] 302
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under such circumstances (e.g., Cameron & Nichols, 1998; Lumley & Provenzano, 2003). Consistent with the intervention(s) proposal of Nolen-Hoeksema et al. (in press), we expected that brooding would moderate the effects of expressive writing on depression symptoms, such that participants with greater brooding scores who were assigned to the expressive writing condition would display reductions in depression symptom severity at follow-up compared with participants with lower brooding scores assigned to that condition. We did not expect that reflective pondering would moderate expressive writing outcome, as these individuals already use an adaptive coping strategy.
Method Participants During a student orientation fair held during the summer before fall matriculation, incoming 1st-year college students were asked to provide their names and contact information if they were interested in potentially volunteering for a study examining the effects of writing on academic performance. Students were informed that they would be contacted at the beginning of the fall semester to make arrangements for their participation. Potential participants were contacted during the first 2 weeks of the fall semester, and all interested participants entered the study between the 3rd and 6th weeks of that semester. Participants were randomly assigned (within gender) to either an expressive writing condition (n ⫽ 35) or a control writing condition (n ⫽ 34). The study was approved by the university Institutional Review Board, and participants received financial compensation ($5 per session) in exchange for their time. Of the 69 students (45 women and 24 men) who entered the study, 1 dropped out after the first writing session (expressive writing condition), 3 failed to return for the 2-month follow-up assessment (2 from the expressive writing condition), 3 failed to return for the 4-month follow-up assessment (2 from the expressive writing condition), and 5 failed to return for the 6-month follow-up assessment (2 from the expressive writing condition). In total, 12 students dropped out of the study before the final follow-up visit, with 7 participants (4 women and 3 men) assigned to the expressive writing condition, and 5 participants (4 women and 2 men) assigned to the control condition (83% retention rate). The data for the 68 students who completed all of the writing sessions were used for the analyses reported here.1 Among the 68 students who completed all of the writing sessions, 33 were White, not of Hispanic origin; 22 were African American; 6 were Asian American; 4 were Hispanic; and 3 were of mixed racial background. The mean age of the sample was 18.0 years (SD ⫽ 0.51), and all participants were single. Consistent with other studies that have allowed participants to select the writing topic (e.g., Epstein et al., 2005; Park & Blumberg, 2002), there was considerable range in the types of events that participants wrote about. Most participants wrote about either an assault (24%) or an illness or injury to themselves or a family member (24%). Others wrote about the end of a close relationship (16%), a family conflict (12%), the death of a close friend or family member (12%), or another stressful life event (10%). Although all of the participants were starting their 1st year in college, only 2% of the expressive writing participants elected to write about their transition to college.
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Measures Ruminative Responses Scale (RRS; Nolen-Hoeksema & Morrow, 1991). The RRS is a 22-item measure that indexes ruminative response style. RRS items are rated using a 4-point Likert-type scale (ranging from 1 ⫽ almost never to 4 ⫽ almost always), with higher scores indicating greater ruminative tendencies. Acceptable convergent and predictive validity for the RRS has been demonstrated (Butler & Nolen-Hoeksema, 1994; Nolen-Hoeksema & Morrow, 1991). Research has shown that ruminative style, as measured by the RRS, is stable over time (Nolen-Hoeksema & Davis, 1999; Nolen-Hoeksema, Morrow, & Fredrickson, 1993). The RRS contains two subscales that assess brooding and reflective pondering, and good internal consistency and test–retest reliability for these two subscales have been reported (Treynor et al., 2003). Higher scores on the Brooding and Reflective Pondering subscales indicate greater tendency toward brooding and reflective pondering, respectively. Depression and Anxiety Stress Scale—21-Item (DASS21; Lovibond & Lovibond, 1995). The DASS21 is a 21-item questionnaire consisting of items relating to depression, hyperarousal, and stress. A Likert-type scale is used to rate items according to symptoms experienced in the past week, ranging from 0 (not at all) to 3 (most of the time). Factor analytic studies with both clinical and nonclinical samples have shown that the DASS21 items can be reliably grouped into three scales: Depression, Anxiety, and Stress (Antony, Bieling, Cox, Enns, & Swinson, 1998). Only the DASS21 Depression subscale was used in this study. This scale has been shown to provide a better separation of the features of anxiety and depression than other existing measures of depression (Antony et al., 1998; Brown, Chorpita, Korotitsch, & Barlow, 1997; Lovibond & Lovibond, 1995). Two-week retest reliability for the DASS21 Depression subscale has been found to be relatively high at .71 (e.g., Antony et al., 1998).
Procedure Participants provided written informed consent on arrival at the first session. In the informed consent procedure, participants were informed that during the experiment, they might be asked to write about stressful or traumatic experiences. The stated purpose of the study (to examine how writing affects academic performance) was made more plausible as participants provided consent for academic performance data to be obtained.2 After providing informed consent, participants completed an assessment packet, which included a demographics questionnaire, the DASS21, and the RRS. Participants were then given an envelope that contained the general instructions for writing and specific instructions for the first writing session, as well as a booklet in which they were instructed to write. Writing instructions for each writing condition and session were replicated from the standard instructions developed by Pen1
The chi-square (racial background and gender) and t-test (age, baseline depression score, brooding score, and reflective pondering score) analyses indicated that participants who dropped out of the study did not significantly differ from participants who completed the study (largest p ⬎ .40, reffect size ⫽ .09). 2 Academic performance data (GPA and SAT scores) were collected but are not related to the purpose of this study and are, therefore, not reported.
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nebaker (1997). Briefly, participants assigned to the expressive writing condition were asked to write about the most stressful or traumatic experience of their lives with as much emotion and feeling as possible. Participants were also asked to write about how the experience was related to other aspects of their lives. At the last writing session, participants were encouraged to “wrap up” their writing by describing how the experience was related to their current lives and futures. Participants assigned to the control writing condition were asked to write about how they spent their time each day without any emotion or opinions. Participants in both conditions wrote continuously for 20 min each session on 3 consecutive days. Participants wrote alone in a private location within the laboratory. After participants read their instructions, they were left alone in the room to write. After 20 min, the experimenter entered the room and instructed the participant to stop writing. Although participants were allowed to keep their written narratives instead of turning them in to the experimenters, no participant elected to keep his or her written narrative. Experimenters were not unaware of participants’ condition assignment. With the exception of completing the baseline questionnaires, the same procedure was followed for the writing sessions on the following 2 days. Participants then returned 2, 4, and 6 months later for their follow-up assessments, during which they completed the DASS21 depression measure. Participants were fully debriefed after completing the 6-month follow-up assessment. Participants who dropped out of the study before the last assessment were asked to return for a debriefing. If they did not return, a letter was sent to them that provided the debriefing information. To determine whether participants believed the stated purpose of the study, a manipulation check was administered following the last writing session. Participants were asked what they believed the study was “trying to prove.” Responses indicated that participants assigned to both conditions had the expectation that the writing sessions would result in some type of academic improvement for them.
Results To investigate the adequacy of randomization, participants assigned to the two writing conditions were compared on demographic and baseline questionnaire measures using chisquares (racial background and gender) and t tests (age, depression symptom severity, brooding, and reflective pondering). No significant between-groups differences in demographic characteristics or baseline questionnaire measures were found (largest p ⬎ .30, reffect size ⫽ .12; Rosenthal, Rosnow, & Rubin, 2000). Summary information on depression and rumination scores, as a function of condition and time, are reported in Table 1.
Ruminative Style as a Moderator of Expressive Writing Outcome Brooding. To examine whether brooding moderated the effects of expressive writing on depression symptoms, we performed standard multiple regressions separately for each follow-up assessment (2, 4, and 6 month). We calculated adjusted outcome means with standardized residuals created by regressing follow-up DASS21 depression symptom severity scores on baseline DASS21 depression symptom severity scores. We then used this residual score as the dependent variable, with writing condition, brooding,
Table 1 Means (and Standard Deviations) at Baseline and Follow-Up Assessments as a Function of Condition Outcome measure DASS21 Depression Baseline 2 month 4 month 6 month Brooding Baseline Pondering Baseline
Control writing
Expressive writing
8.4 (7.9) 8.7 (6.4) 8.2 (8.1) 8.1 (8.3)
9.5 (8.3) 4.2 (9.2) 8.6 (9.8) 9.3 (8.6)
5.6 (3.9)
5.7 (4.3)
5.2 (4.4)
5.6 (4.6)
Note. DASS21 ⫽ Depression and Anxiety Symptom Scale—21-Item.
and the Writing Condition ⫻ Brooding interaction term entered into the regression model. Following the guidelines of West, Aiken, and Krull (1996), the brooding score was centered. The full model predicting depression outcome at the 2-month follow-up assessment was significant, F(3, 64) ⫽ 7.70, p ⬍ .001, reffect size ⫽ .32, R2 ⫽ .28. Significant main effects were observed for condition and brooding, which were qualified by a significant Writing Condition ⫻ Brooding interaction ( ⫽ ⫺0.41, p ⬍ .05). To further explore the significant interaction, we conducted regression analyses separately for each writing condition using DASS21 depression residual score as the dependent variable and brooding as the predictor variable. Results indicated that brooding was a significant predictor of depression outcome for the expressive writing condition (R2 ⫽ .42,  ⫽ ⫺0.64, p ⬍ .001), whereas it was not a significant predictor for the control writing condition (R2 ⫽ .07,  ⫽ ⫺0.26, p ⬎ .14). Thus, brooding moderated expressive writing outcome, with expressive writing participants who displayed a greater tendency toward brooding reporting less depression symptom severity at the 2-month follow-up assessment. The brooding moderating effect is illustrated in Figure 1. Findings for the 4- and 6-month follow-up assessments revealed a similar pattern. The full model predicting depression symptom severity at the 4-month assessment was significant, F(3, 64) ⫽ 5.65, p ⬍ .01, R2 ⫽ .23, reffect size ⫽ .23. A marginally significant Writing Condition ⫻ Brooding interaction was observed ( ⫽ ⫺0.37, p ⫽ .06). Follow-up tests indicated that expressive writing participants with a greater tendency toward brooding reported a significant decrease in depression symptom severity at the 4-month follow-up assessment (R2 ⫽ .27,  ⫽ ⫺0.519, p ⬍ .01), although this moderator effect was not observed for the control writing participants (R2 ⫽ .07,  ⫽ ⫺0.26, p ⬎ .30). The full model predicting depression outcome was also significant for the 6-month follow-up assessment, F(3, 64) ⫽ 3.55, p ⬍ .05, R2 ⫽ .17, reffect size ⫽ .22. A significant Writing Condition ⫻ Brooding interaction ( ⫽ ⫺0.49, p ⬍ .05) was found. Follow-up tests again indicated that expressive writing participants with higher baseline brooding scores displayed a significant decrease in depression symptom severity at the 6-month follow-up assessment (R2 ⫽ .15,  ⫽ ⫺0.43, p ⬍ .05), whereas this moderator effect was not observed for control writing participants (R2 ⫽ .05,  ⫽ 0.07, p ⬎ .70). Reflective pondering. To examine reflective pondering as a moderator of the effects of expressive writing on depression symp-
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Depression Change Score
6 4 2 Low Brooding High Brooding
0 -2 -4 -6
Control
Expressive
Figure 1. A median split was used to create high and low brooding groups for each writing condition. The figure illustrates depression symptom severity change (2-month follow-up assessment– baseline assessment) as a function of writing condition and high versus low brooding style.
tom severity, we used the same analytic strategy that we used to examine brooding as a moderator. As predicted, results indicated that reflective pondering did not moderate the effects of expressive writing on depression symptom severity at any of the follow-up assessments. The full models predicting 2-, 4-, and 6-month depression symptom severity were significant, F(3, 64) ⫽ 4.64, p ⬍ .01, largest R2 ⫽ .19, reffect size ⫽ .26. However, the Writing Condition ⫻ Reflective Pondering interaction was not significant at the 2-month ( ⫽ ⫺0.27, p ⬎ .14), 4-month ( ⫽ ⫺0.23, p ⬎ .20), or 6-month ( ⫽ ⫺0.19, p .15) follow-up assessments.
Discussion The findings reported here indicate that the effects of brooding can be undone with a brief and easily implemented intervention. Although the expressive writing intervention requires three sessions consisting of a total of just 60 min, the time spent appeared to be sufficient to reduce depression symptom severity among participants with a tendency to brood. Moreover, the efficacy of the intervention persisted for 6 months. The durability of the benefits for brooders is particularly striking given that a metaanalysis of expressive writing research indicated that the benefits of the intervention tend to be short lived (see Frattaroli, 2006). In line with previous hypotheses regarding the mechanisms of action for expressive writing (e.g., Sloan & Marx, 2004) and the speculations of Nolen-Hoeksema et al. (in press), we propose that the expressive writing sessions may allow brooders to confront their negative thoughts and feelings, use more constructive problem-solving skills, and restructure maladaptive cognitions regarding their stressful experiences, all of which served to ward off further increases in stress that they would otherwise have experienced and led to or maintained future depression symptoms. Another possible explanation is that the expressive writing intervention prompted the participants to seek out social support. That is, writing about stressful or traumatic experiences provoked the participants to discuss what they had written about with others, which, in turn, strengthened their social bonds. The strengthened social bonds hypothesis has been suggested by Pennebaker (1997) to account for what maintains beneficial outcomes resulting from expressive writing. Seeking out social support would be particularly beneficial for brooders as these individuals have been found to socially isolate themselves (Nolen-Hoeksema & Davis, 1999).
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Moreover, people who are socially isolated or who do not receive emotional support from others are less likely to use active coping strategies (e.g., Holahan & Moos, 1987). Consequently, the increase in social bonds would serve as a positive distraction from brooding and would increase the likelihood that these individuals would engage in active coping strategies to address ongoing stressors they might have been experiencing. As the purpose of this study was to examine ruminative style as a moderator of the effects of expressive writing, we did not focus our investigation on exploring possible mechanisms of action. Also, our relatively small sample size did not permit us to adequately investigate underlying mechanisms associated with the beneficial outcome for brooders. Nonetheless, there are a number of well-articulated theories to account for why expressive writing leads to beneficial outcomes among brooders. It will be important for future research to investigate the proposed underlying mechanisms given the observed reduction in depressive symptom severity obtained in this study and the resiliency of the benefits derived from the intervention. The results of this study suggest that although expressive writing may be particularly beneficial in reducing depressive symptom severity among brooders, it may not work as well for those with a tendency to reflectively ponder. Although expressive writing is generally associated with psychological and physical health benefits, individuals who already engage in more adaptive coping efforts may be less likely to gain benefits from this intervention. Although we found expressive writing to be beneficial for brooders, we examined a relatively high-functioning sample of young individuals (i.e., college students). Whether these findings would generalize to samples who display a greater tendency toward brooding and greater impairment is unknown. It seems likely that more severe samples would require a greater number of expressive writing sessions to reap similar benefits. Overall, the findings obtained in this study indicate that the expressive writing intervention may be particularly beneficial for brooders. What is less clear from this study is how expressive writing counteracts the detrimental effects of brooding. Gaining a greater understanding of the types of intervention techniques that are effective in treating maladaptive rumination, and why these interventions are effective, is an important direction for rumination research.
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Received May 30, 2007 Revision received January 3, 2008 Accepted January 7, 2008 䡲
