Despite these limitations, results from the present study may have implications for future research on mindfulness and thought suppression among people with GAD. The primary aim of the present study was to detect if a brief mindfulness manipulation reduces the impact of worry on subsequent negative affect and emotion dysregulation. The present study indicates that a single, brief mindfulness manipulation may not have this hypothesized “buffering” effect for people with analogue GAD when they have been worrying. Brief mindfulness instructions may not actually operate to aid in emotion regulation under distress, in the immediate sense. Indeed, theoretically, mindfulness meditation may even be distressing and destabilizing in the early stages of practice (A. M. Hayes & Feldman, 2004). However, it could increase access to the full range of affective experience for those who have recently been worrying, allowing for increased positive affect, even though negative affect does not decrease substantially if worry is followed by mindfulness. The mindfulness manipulation did appear to reduce negative affective
responding, but this effect appeared driven by participants who were not induced to worry. This indicates that there may be specific circumstances under which a brief mindfulness manipulation is an immediately effective tool for coping with aversive stimuli. It is possible that a mindfulness manipulation may be most helpful for downregulating negative affect when people with GAD
have not recently been worrying, whereas it may allow for both positive and negative affect to arise following worry.
However, this possibility should be examined using a larger dose of mindfulness. In the present study, the five-minute mindfulness manipulation was not sufficient to affect state mindfulness in participants. This lack of effect on state mindfulness may have reduced the potential regulatory properties of the mindfulness manipulation. It is possible that simply increasing the length of time of the manipulation would have yielded effects on state
mindfulness, but it may also be that people with GAD need to practice mindfulness multiple times in order to achieve benefits. This indicates that a dose-response study of mindfulness for GAD may be a necessary next step to guide further experimental research on the effects of a mindfulness manipulation in this population.
The results of the present study also suggest that there may be specific circumstances where thought suppression, in the brief and immediate sense, is effective for emotion regulation. Interaction effects were not significant, but unexpected trends emerged from the data. Following worry, thought suppression appeared to decrease emotion dysregulation in response to the film,
whereas thought suppression increased emotion dysregulation as hypothesized following a no- worry control condition. These trends are surprising, and they indicate that those with GAD may be motivated to use thought suppression because it could aid in emotion regulation, at least temporarily. People with GAD likely use worry for a similar reason; in the short term, worry reduces negative affective responding and blunts physiological responding to stressful stimuli (Borkovec & Hu, 1990). If thought suppression reduces dysregulated responding to aversive stimuli following worry, its use may be maintained by negative reinforcement. For people with GAD in particular, a strategy that is useful following a worry episode may be strongly reinforced
due to the frequency of worry in this population. It is unknown if thought suppression would have had rebound effects over time; the present study did not include a follow-up to examine the longer-term effects of the experimental conditions. However, these results indicate that thought suppression in GAD is deserving of further exploration.
First, an identical design to the present study, but without the comparison to mindfulness, may have increased power to detect significant results of potential interactions. The trends of the present study indicate that with increased power, interaction effects may have emerged regarding the effects of thought suppression on emotion dysregulation. However, indicating that thought suppression is helpful for short-term emotion dysregulation may be misleading without a follow- up period, because it may not capture the longer-term rebound effects of thought suppression that have been reported in the literature (Abramowitz et al., 2001). Thus, future research should examine the effects of thought suppression following worry using a follow-up period to examine potential rebound effects on negative affect and emotion dysregulation.
Future researchers may also consider adding multimodal assessment of the dependent variables used in the present study. Specifically, there are physiological measures of both negative affect (i.e., cardiac reactivity) and emotion dysregulation (i.e., heart rate variability; Appelhans & Luecken, 2006). Additionally, there are behavioral indicators of emotion
dysregulation, such as willingness to tolerate an aversive stimulus, which may indicate increased emotional tolerance, an important facet of emotion regulation. Arch and Craske (2006) found that mindfulness did alter behavior on an emotional tolerance task, more than their “unfocused attention” control, even with a brief mindfulness exercise with inexperienced meditators. It may be that there are particular facets of emotion regulation that can be most effectively targeted by mindfulness in the immediate sense. Multimodal assessment of negative affect and emotion
dysregulation may help to rule out potential measurement issues, and would help to identify specific processes that may be targeted by mindfulness.