The Salivary Biochemical Changes Associated with a Mood Induction Writing Task

Writing about emotionally salient topics to influence a participant’s mood is a common experimental technique in emotion research. This study attempted to begin the biological characterization of this research paradigm. Thirtyeight participants were: 1) administered the Positive and Negative Affect Schedule (PANAS) and asked to provide a saliva sample, 2) assigned to either an emotionally positive or negative writing task, and 3) re-administered the PANAS and asked to provide another saliva sample. Saliva samples were analyzed using ELISA for concentration of a stress hormone (cortisol), an immunological marker (secretory immunoglobulin A), and a sex steroid (dehydroepiandrosterone). Both writing tasks were found to influence mood in the appropriate manner. That is, the positive writing task increased positive mood and the negative writing task increased negative mood. The negative writing task was found to lower salivary cortisol concentration. The ability for the negative writing task to attenuate stress hormone levels is discussed in the context of this research paradigm’s potential similarity to expressive written therapy. The study of emotion commonly relies on techniques that can produce mood alterations in a laboratory setting. One frequently utilized technique has been the mood induction writing task. In this task, participants are asked to write about an emotionally arousing subject (e.g., the saddest time in their life) while control-group participants are asked to write about a neutral topic (e.g., the contents of a geography article; Baker & Guttfreund, 1993). This experimental technique has the benefits of requiring a short amount of time (approximately 20-30 minutes), necessitating few resources, produces a fairly large effect, and possesses few risks for the experimental subject (Baker & Guttfreund, 1993). While the mood induction writing task has been used in many psychological experiments, no research has focused on the biological changes that accompany this technique. In studies using a naturalistic setting, positive and negative moods have been associated with certain biological characteristics. For example, positive affect is associated with decreased release of the stress hormone cortisol (Lai, Evans, Ng, Chong, Siu, Chan, Ho, Ho, Chan, & Chan, 2005), exacerbated androgen release (Booth, Shelley, Mazur, & Tharp, 1989) and increased immune system function (Stone, Cox, Valdimarsdottir, Jandorf, & Neale, 1987). Conversely, negative affect is associated with increased cortisol release (Smyth, Ockenfels, Porter, Kirschbaum, Hellhammer, & Stone, 1998), decreased androgen release (van Niekerk, Huppert, & Herbert, 2001) and decreased immune system function (Stone et al., 1987). Based on the similarity between one’s self-reported mood in the writing task and a naturalistic setting, it could be argued that similar biological changes would occur in the mood induction writing task. However, the writing task mimics many aspects of a therapeutic practice that has produced physical changes incongruent with this hypothesis. The therapeutic practice of self-disclosure has been studied extensively by James Pennebaker (for reviews see: Pennebaker, 1997; Pennebaker & Chung, 2007). In this paradigm, a person repeatedly writes about a BIOCHEMICAL PROFILE OF MOOD Vol 5, Issue 1 December 2008 38 topic that has been negatively affecting his or her life over an extended period of time (i.e., days to months). This paradigm has shown positive therapeutic outcomes for a wide range of issues, including depressive symptomology (Gortner, Rude, & Pennebaker, 2006), insomnia (Harvey & Farrell, 2003), smoking cessation (Ames, Patten, Offord, Pennebaker, Croghan, Tri, Stevens, & Hurt, 2005; Ames, Patten, Werch, Schroeder, Stevens, Fredrickson, Echols, Pennebaker, & Hurt, 2007), stress due to job loss (Spera, Buhrfeind, & Pennebaker, 1994), and work absenteeism (Francis & Pennebaker, 1992). Interestingly, positive changes to participants’ health have been a consistent outcome in this paradigm in spite of the maintenance of a negative mood. For example, in one study, adults suffering from fibromyalgia were assigned into either a disclosure group, which wrote for four consecutive days about life stress, or a control group, which wrote for four consecutive days about a neutral topic (Gillis, Lumley, Mosley-Williams, Leisen, & Roehrs, 2006). At a one-month follow-up, the disclosure group, relative to the control group, showed signs of improvement in sleep quality, fatigue, pain, and physical disability. However, the disclosure group also experienced a significant worsening of mood and perceived social support. At the 3-month follow-up point, the previously mentioned biological factors of the disease continued to show improvement relative to the control group but the negative effects on mood and perceived social support were no longer evident. This mismatch between health improvement and negative mood leads one to question whether the operationallysimilar mood induction writing task could produce biological changes that are diametrically-opposed to those caused by moods induced in a naturalistic setting. In this experiment, the effects of a mood induction writing task on the release of the stress hormone cortisol, the immune system marker secretory immunoglobulin A (SIgA) and the sex steroid dehydroepiandrosterone (DHEA) were investigated. Participants were assigned to one of two writing task groups: the positive writing task group wrote for 30 min about someone they love and the negative writing task group wrote for 30 min about someone they hate. Participants completed a self-report mood survey both before and after the writing task to assess any change in mood. Also, participants provided a saliva sample both before and after the writing task for the assessment of any biological changes. The saliva was analyzed via Enzyme-Linked ImmunoAssorbent Assay (ELISA) for changes in cortisol, SIgA, and DHEA.