Neural mechanisms of symptom improvements in generalized anxiety disorder following mindfulness training.

Author: Hölzel BK, Hoge EA, Greve DN, Gard T, Creswell JD, Brown KW, Barrett LF, Schwartz C, Vaitl D, Lazar SW.
Affiliation: Massachusetts General Hospital, 120 2nd Ave., Charlestown, MA, 02129, USA ; Bender Institute of Neuroimaging, Justus-Liebig University, Otto-Behaghel-Str. 10H, 35394 Giessen, Germany.
Conference/Journal: Neuroimage Clin.
Date published: 2013 Mar 25
Other: Volume ID: 2 , Pages: 448-58 , Special Notes: doi: 10.1016/j.nicl.2013.03.011 , Word Count: 272



Mindfulness training aims to impact emotion regulation. Generalized anxiety disorder (GAD) symptoms can be successfully addressed through mindfulness-based interventions. This preliminary study is the first to investigate neural mechanisms of symptom improvements in GAD following mindfulness training. Furthermore, we compared brain activation between GAD patients and healthy participants at baseline. 26 patients with a current DSM-IV GAD diagnosis were randomized to an 8-week Mindfulness Based Stress Reduction (MBSR, N = 15) or a stress management education (SME, N = 11) active control program. 26 healthy participants were included for baseline comparisons. BOLD response was assessed with fMRI during affect labeling of angry and neutral facial expressions. At baseline, GAD patients showed higher amygdala activation than healthy participants in response to neutral, but not angry faces, suggesting that ambiguous stimuli reveal stronger reactivity in GAD patients. In patients, amygdala activation in response to neutral faces decreased following both interventions. BOLD response in ventrolateral prefrontal regions (VLPFC) showed greater increase in MBSR than SME participants. Functional connectivity between amygdala and PFC regions increased significantly pre- to post-intervention within the MBSR, but not SME group. Both, change in VLPFC activation and amygdala-prefrontal connectivity were correlated with change in Beck Anxiety Inventory (BAI) scores, suggesting clinical relevance of these changes. Amygdala-prefrontal connectivity turned from negative coupling (typically seen in down-regulation of emotions), to positive coupling; potentially suggesting a unique mechanism of mindfulness. Findings suggest that in GAD, mindfulness training leads to changes in fronto-limbic areas crucial for the regulation of emotion; these changes correspond with reported symptom improvements.
KEYWORDS:
Amygdala, Beck Anxiety Inventory, Connectivity, Emotion regulation, Generalized anxiety disorder, Intervention, Longitudinal, Mindfulness, Prefrontal cortex, Stress, Ventrolateral prefrontal cortex

PMID: 24179799 [PubMed] PMCID: PMC3777795