Mindfulness-Based Stress Reduction, Fear Conditioning, and The Uncinate Fasciculus: A Pilot Study - PubMed (original) (raw)

Mindfulness-Based Stress Reduction, Fear Conditioning, and The Uncinate Fasciculus: A Pilot Study

Britta K Hölzel et al. Front Behav Neurosci. 2016.

Abstract

Mindfulness has been suggested to impact emotional learning, but research on these processes is scarce. The classical fear conditioning/extinction/extinction retention paradigm is a well-known method for assessing emotional learning. The present study tested the impact of mindfulness training on fear conditioning and extinction memory and further investigated whether changes in white matter fiber tracts might support such changes. The uncinate fasciculus (UNC) was of particular interest in the context of emotional learning. In this pilot study, 46 healthy participants were quasi-randomized to a Mindfulness-Based Stress Reduction (MBSR, N = 23) or waitlist control (N = 23) group and underwent a two-day fear conditioning, extinction learning, and extinction memory protocol before and after the course or control period. Skin conductance response (SCR) data served to measure the physiological response during conditioning and extinction memory phases. Diffusion tensor imaging (DTI) data were analyzed with probabilistic tractography and analyzed for changes of fractional anisotropy in the UNC. During conditioning, participants were able to maintain a differential response to conditioned vs. not conditioned stimuli following the MBSR course (i.e., higher sensitivity to the conditioned stimuli), while controls dropped the response. Extinction memory results were not interpretable due to baseline differences. MBSR participants showed a significant increase in fractional anisotropy in the UNC, while controls did not (group by time interaction missed significance). Pre-post changes in UNC were correlated with changes in the response to the conditioned stimuli. The findings suggest effects of mindfulness practice on the maintenance of sensitivity of emotional responses and suggest underlying neural plasticity. (ClinicalTrials.gov, Identifier NCT01320969, https://clinicaltrials.gov/ct2/show/NCT01320969).

Keywords: diffusion tensor imaging; fear conditioning; fear extinction; meditation; mindfulness; neuroplasticity; uncinate fasciculus.

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Figures

Figure 1

Figure 1

Participant flow chart.

Figure 2

Figure 2

The total number of hours of mindfulness home practice in the mindfulness-based stress reduction (MBSR) group predicts the total scores of (A) the Perceived Stress Scale (PSS); (B) Difficulties in Emotion Regulation Scale (DERS); and (C) Mindful Attention Awareness Scale (MAAS) at post.

Figure 3

Figure 3

Skin conductance response (SCR) to CS+ and CS− in the conditioning phase at pre and post in the MBSR and control groups. Bars represent standard error of the mean.

Figure 4

Figure 4

Correlation between the change in perceived stress from pre to post and the change from pre to post in differential conditioning (the difference of the SCR response to CS+ vs. the response to CS−) across the MBSR (black square) and control (red star) groups.

Figure 5

Figure 5

Mean of the weighted averaged fractional anisotropy within the right uncinate fasciculus (UNC) in the control and MBSR groups before (pre) and after (post) the MBSR course or wait period respectively. Bars represent standard error of the mean.

Figure 6

Figure 6

The pre-post change in SCR in response to the CS+ is positively correlated with the pre-post change in fractional anisotropy (FA) in the right UNC across the MBSR (black square) and control (red star) groups (r(22) = 0.422, p = 0.040).

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References

    1. Antonova E., Chadwick P., Kumari V. (2015). More meditation, less habituation? The effect of mindfulness practice on the acoustic startle reflex. PLoS One 10:e0123512. 10.1371/journal.pone.0123512 - DOI - PMC - PubMed
    1. Baer R. A. (2003). Mindfulness training as a clinical intervention: a conceptual and empirical review. Clin. Psychol. Sci. Pract. 10, 125–143. 10.1093/clipsy.bpg015 - DOI
    1. Banks S. J., Eddy K. T., Angstadt M., Nathan P. J., Phan K. L. (2007). Amygdala-frontal connectivity during emotion-regulation. Soc. Cogn. Affect. Neurosci. 2, 303–312. 10.1093/scan/nsm029 - DOI - PMC - PubMed
    1. Baur V., Hänggi J., Jäncke L. (2012). Volumetric associations between uncinate fasciculus, amygdala and trait anxiety. BMC Neurosci. 13:4. 10.1186/1471-2202-13-4 - DOI - PMC - PubMed
    1. Baur V., Hänggi J., Rufer M., Delsignore A., Jäncke L., Herwig U., et al. . (2011). White matter alterations in social anxiety disorder. J. Psychiatr. Res. 45, 1366–1372. 10.1016/j.jpsychires.2011.05.007 - DOI - PubMed

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