Self-Reported Trait Mindfulness and Affective Reactivity: A Motivational Approach Using Multiple Psychophysiological Measures

<div><p>As a form of attention, mindfulness is qualitatively receptive and non-reactive, and is thought to facilitate adaptive emotional responding. One suggested mechanism is that mindfulness facilitates disengagement from an affective stimulus and thereby decreases affective reactivity. However, mindfulness has been conceptualized as a state, intervention, and trait. Because evidence is mixed as to whether self-reported trait mindfulness decreases affective reactivity, we used a multi-method approach to study the relationship between individual differences in self-reported trait mindfulness and electrocortical, electrodermal, electromyographic, and self-reported responses to emotional pictures. Specifically, while participants (N = 51) passively viewed pleasant, neutral, and unpleasant IAPS pictures, we recorded high-density (128 channels) electrocortical, electrodermal, and electromyographic data to the pictures as well as to acoustic startle probes presented during the pictures. Afterwards, participants rated their subjective valence and arousal while viewing the pictures again. If trait mindfulness spontaneously reduces general emotional reactivity, then for individuals reporting high rather than low mindfulness, response differences between emotional and neutral pictures would show relatively decreased early posterior negativity (EPN) and late positive potential (LPP) amplitudes, decreased skin conductance responses, and decreased subjective ratings for valence and arousal. High mindfulness would also be associated with decreased emotional modulation of startle eyeblink and P3 amplitudes. Although results showed clear effects of emotion on the dependent measures, in general, mindfulness did not moderate these effects. For most measures, effect sizes were small with rather narrow confidence intervals. These data do not support the hypothesis that individual differences in self-reported trait mindfulness are related to spontaneous emotional responses during picture viewing.</p></div

Correlations between self-reported measures.

<p>^†Scores are the means across non-missing items except for STAI-T and BDI, which represent the sums across all items.</p><p>*<i>p</i> < .05 (2-tailed)</p><p>**<i>p</i> < .01 (2-tailed)</p><p><i>N</i> = 51. MAAS = Mindful Attention Awareness Scale; FFMQ = Five Facet Mindfulness Questionnaire; FFMQ-AWA = Acting with awareness subscale; FFMQ-NJ = Non-judging subscale; FFMQ-NR = Nonreactivity subscale; STAI-T = Staite-Trait Anxiety Inventory, trait scale; BDI = Beck Depression Inventory.</p><p>Correlations between self-reported measures.</p

Results for the P3 to startle probes.

<p>(A) Grand average waveforms of the P3-relevant electrodes for the three picture categories across participants. Note that the P3 per se is the positivity between 300 and 380 ms after startle onset, and an arousal effect on the P3 would be apparent as a greater positivity for neutral pictures than arousing (i.e., pleasant and unpleasant) pictures. (B) Magnified version of (A) for individuals with high and low self-reported trait mindfulness separately. (C) Graphs depicting the mean amplitudes of the P3-relevant electrodes between 300 and 380 ms after picture onset for the three picture categories for all participants (left, <i>N</i> = 51) and for high (<i>n</i> = 25) and low (<i>n</i> = 26) self-reported trait mindfulness separately (right). (D) Topographical distribution of the mean amplitude differences between 300 and 380 ms after picture onset between the combined pleasant and unpleasant pictures versus neutral pictures, with electrodes selected for analysis in magenta (A4, A19 (Pz), and A20). The 95% <i>CI</i> refers to each individual condition mean. FFMQ-NR = Nonreactivity subscale of the FFMQ.</p

Results for the late positive potential (LPP) to picture onset.

<p>(A) Grand average waveforms of the LPP-relevant electrodes for the three picture categories across participants. Note that the arousal effect on the LPP is apparent as the relative positivity between 400 and 800 ms after picture onset for arousing (i.e., pleasant and unpleasant) pictures versus neutral pictures. (B) Magnified version of (A) for individuals with high and low self-reported trait mindfulness separately. (C) Graphs depicting the mean amplitudes of the LPP-relevant electrodes between 400 and 800 ms after picture onset for the three picture categories for all participants (left, <i>N</i> = 51) and for high (<i>n</i> = 25) and low (<i>n</i> = 26) self-reported trait mindfulness separately (right). (D) Topographical distribution of the mean amplitude differences between 400 and 800 ms after picture onset between the arousing (i.e., combined pleasant and unpleasant) pictures versus neutral pictures, with electrodes selected for analysis in magenta (A1 (Cz), A2, A3 (CPz), A4, A19 (Pz), D1, D15, D16, C1, B1, and B2). The 95% <i>CI</i> refers to each individual condition mean. FFMQ-NR = Nonreactivity subscale of the FFMQ.</p

Mean responses for valence ratings, startle EMG, arousal ratings, and skin conductance responses.

<p>Mean responses are reported across picture categories for all participants (top row) and for high and low self-reported trait mindfulness separately (FFMQ-NR; bottom row). A median split was used to dichotomize high and low self-reported trait mindfulness (<i>N</i> = 51, <i>n</i> = 25 in the high group and <i>n</i> = 26 in the low group; for SCR, one individual was missing in each group). The 95% <i>CI</i> refers to each individual condition mean.</p

Results for the early posterior negativity (EPN) to picture onset.

<p>(A) Grand average waveforms of the EPN-relevant electrodes for the three picture categories across participants. Note that the EPN per se is a relative negativity between 200 and 300 ms after picture onset for pleasant and unpleasant pictures versus neutral pictures. (B) Magnified version of (A) for individuals with high and low self-reported trait mindfulness separately. (C) Graphs depicting the mean amplitudes of the EPN-relevant electrodes between 200 and 300 ms after picture onset for the three picture categories for all participants (left, <i>N</i> = 51) and for high (<i>n</i> = 25) and low (<i>n</i> = 26) self-reported trait mindfulness separately (right). (D) Topographical distribution of the mean amplitude differences between 200 and 300 ms after picture onset between the combined pleasant and unpleasant pictures versus neutral pictures, with electrodes selected for analysis in magenta (left: D32, A10 (PO7), A11, A12, A13, A14; and right: A26, A27, B7 (PO8), B8, B9, B10). The 95% <i>CI</i> refers to each individual condition mean. FFMQ-NR = Nonreactivity subscale of the FFMQ.</p

Inferential statistics for valence and arousal measures across participants and as related to self-reported mindfulness (FFMQ-NR).

<p><i>N</i> = 51 (except for SCR, <i>N</i> = 49). FFMQ-NR = Nonreactivity subscale of the FFMQ; Unp = unpleasant pictures; Ple = pleasant pictures; Neu = neutral pictures; Aro = unpleasant + pleasant pictures combined. Note that the inferential statistics (i.e., <i>df</i>, <i>F</i>, <i>p</i>, and <i>η</i>_p²) are taken from an ANCOVA with Emotion (i.e., picture category) as within-subjects factor (and also with Interval for EMG and P3) and FFMQ-NR as a continuous and centered covariate (to maximize power). “M_diff” refers to the mean differences between conditions or groups specified under “Hypothesis.” Accordingly, valence and arousal contrasts refer to the hypothesized differences between picture categories across participants. For all measures, these M_diff scores across participants were expected to be positive. To illustrate the moderating effects of FFMQ-NR, a median split was performed and difference scores for individuals with low scores (<i>n</i> = 26) were subtracted from difference scores for individuals with high scores (<i>n</i> = 25). Because for all measures, the main hypothesis was that high FFMQ-NR individuals would show lower affective reactivity than low FFMQ-NR individuals, only negative M_diff scores were expected for the interactions between FFMQ-NR and the valence or arousal contrasts.</p><p>Inferential statistics for valence and arousal measures across participants and as related to self-reported mindfulness (FFMQ-NR).</p

Meta-analysis of how visual task demands changed the MMN (forest plot on left and funnel plot on right).

<p>The analysis focused on the mean amplitudes at Fz (between about 100 and 250 ms after stimulus onset) and was expressed in μV (with 95% CI). The overall negative effect shows that the MMN (i.e., deviant minus standard) was more negative during low than high visual demands (i.e., MMN during low demands minus MMN during high demands). See main text for references to the individual studies. In the forest plot (left), the size of each square corresponds to the weight in the meta-analysis.</p

Mean amplitudes (referenced to tip of nose) for the four conditions (Deviance x Load) across 160–220 ms after tone onset at Fz (left) and Cz (right).

<p>The top row shows condition means (95% CI for each variable), and the bottom row shows mean difference scores (95% CI for the differences) between conditions for effects of load (low minus high), tone deviance (deviant minus standard), and the interaction (i.e., [deviant–standard at low load]–[deviant–standard at high load]).</p

Grand mean (<i>N</i> = 28) ERP difference waves (deviant minus standard, referenced to tip of nose) after tone onset at Fz (top), Cz (middle), and mastoids (bottom) for low and high perceptual load (left), the subsequent difference of low load minus high load (middle), and a scatterplot of individual mean MMN amplitudes (i.e., deviant minus standard) for low and high load (right).

<p>For visualization purposes only, the ERPs were low-pass filtered (30 Hz, 6 dB roll-off, Butterworth).</p