Posted 06.17.2016 | by AMRA

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One advantage of being mindful is that it allows one to respond to situations with equanimity rather than reacting emotionally in a “knee-jerk” fashion. How does mindfulness help us to do this? According to one theory, mindfulness helps to extinguish our negative emotional reactions. It does this by increasing our exposure to the stimuli that provoke these reactions while helping us to maintain an open, nonjudgmental stance.

Uusberg et al. [Biological Psychology] tested this theory using an electroencephalogram (EEG) to measure the effects of repeatedly viewing negative and neutral images under both mindful and control conditions. They hypothesized that repeated viewing of emotionally-charged images while maintaining mindful awareness would cause a greater reduction in emotional reactions to the images than viewing them without mindfulness.

The researchers recruited 37 meditation-naive volunteers (84% female, average age=27). The participants were shown a series of 30 neutral and 30 negative images while an EEG recorded their late positive potentials (LPPs) in response to those images. LPPs are electrical brain waves that occur 260-1500 milliseconds after viewing a stimulus. They reflect ongoing emotional processing, with larger LPPs reflecting greater degrees of emotional processing. The mean difference in LPP amplitude between negative and neutral images served as a measure of emotional reactivity.

The negative stimuli featured images such as car accidents and brutal attacks, while the neutral stimuli were images of everyday scenes and objects such as hairdryers. Participants viewed subsets of these neutral and negative images under three different conditions: an “attentiveness” condition in which they focused on the visual details of the images; an open-monitoring “mindfulness” condition in which they viewed the images while also attending nonjudgmentally to thoughts, feelings, and bodily sensations; and a “distraction” condition in which they viewed the images while mentally counting backwards.

There was a brief period of instruction prior to each of these viewing conditions. Each image in a subset was presented three times during a viewing condition. Afterward, participants were re-exposed to all of the previously seen images and rated them for valence and arousal. Participants also completed measures of trait (the Mindful Attention Awareness Scale) and state (the Toronto Mindfulness Scale) mindfulness immediately after the experiment.

In general, negative images produced significantly larger LPPs than neutral images (η2p=.75). Viewing while “distracted” yielded significantly smaller LPPs than viewing while “attentive” or “mindful” (η2p=.14), and LPP magnitude significantly decreased with repeated presentations (η2p=.17). During the “mindfulness” condition, LPPs were significantly larger for negative than for neutral images for the first two presentations, but this difference disappeared by the third presentation.

This finding is in line with the hypothesis that mindfulness successfully decreases emotional reactivity to the negative images over time. There was no similar pattern of decrease in the difference between negative and neutral LPPs under either the “attentive” or “distracted” viewing conditions.

While state mindfulness wasn’t associated with decreased negative image LPPs under the “mindful” viewing condition, one of its components—“decentering”—was significantly associated with increased neutral image LPPs under same condition. This finding is unexpected and open to a variety of interpretations.

Trait mindfulness, on the other hand, was significantly associated with both decreased negative image LPPs and increased neutral image LPPs during the final re-exposure trial. This suggests that trait mindfulness helps maintain reduced emotional reactivity under later non-mindful viewing conditions.

These results support the theory that mindful viewing enhances the emotional processing of novel stimuli while decreasing emotional reactivity to later repetitions of those stimuli. This decreased reactivity persisted on final re-exposure, especially for participants reporting higher levels of trait mindfulness.

“Mindful” viewing also attenuated LLP components beginning less than 500 milliseconds after stimulus onset, whereas “attentive” and “distracted” viewing did not. These “early” LLP components reflect automatic emotional reactivity rather than deliberate cognitive strategies. In other words, mindfulness has a unique impact on emotional processes that are not under conscious control. The interpretation of study results is limited by the brief nature of its “mindfulness” induction.

Reference:

Uusberg, H., Uusberg, A., Talpsep, T., & Paaver, M. (2016). Mechanisms of mindfulness: The dynamics of affective adaptation during open monitoring. Biological Psychology.

[Link to abstract]