Interoception Underlies Therapeutic Effects of Mindfulness Meditation for Post-Traumatic Stress Disorder: A Randomized Clinical Trial
Author: Seung Suk Kang1, Scott R Sponheim2, Kelvin O Lim3
Affiliation:
1 Department of Biomedical Sciences, University of Missouri-Kansas City, Kansas City, MO, 64108, USA. Electronic address: kangseung@umkc.edu.
2 Veterans Affairs Health Care System, Minneapolis, MN, 55417, USA; Department of Psychiatry, University of Minnesota, Minneapolis, MN, 55455, USA.
3 Department of Psychiatry, University of Minnesota, Minneapolis, MN, 55455, USA; Veterans Affairs Health Care System, Minneapolis, MN, 55417, USA.
Conference/Journal: Biol Psychiatry Cogn Neurosci Neuroimaging
Date published: 2021 Oct 21
Other:
Special Notes: doi: 10.1016/j.bpsc.2021.10.005. , Word Count: 256
Background:
Mindfulness-based interventions have proven efficacy in treating post-traumatic stress disorder (PTSD) but the neurobiological mechanism underlying the therapeutic effects is unknown. As mindfulness meditation cultivates attention to the present-moment and bodily sensations, neural functions related to interoception (i.e., central processes of bodily signals) might be such a mechanism.
Methods:
We conducted a clinical trial in which veterans with PTSD were randomly assigned to receive an 8-week mindfulness-based stress reduction (MBSR) intervention (n = 47) or an active control intervention (present-centered group therapy; PCGT; n = 51). We assessed pre- and post-intervention PTSD symptoms and electroencephalography (EEG) measures of neural outcomes, including spontaneous brain activity, cognitive task-related brain responses, and interoceptive brain responses (heartbeat-evoked brain responses [HEBR]). We conducted statistical causal mediation analyses using treatment type as a predictor, and pre- and post-intervention measures of symptom severity as treatment response, and the neural outcomes as mediators.
Results:
Compared to controls, the MBSR group had greater improvements in PTSD symptoms and increases in spontaneous alpha (8-13 Hz) power, task-related frontal theta power (4-7 Hz in 140-220 ms post-stimulus), and frontal theta HEBR (3-5 Hz and 265-336 ms post-R-peak). The mediation analysis using latent difference score modeling revealed that only changes in frontal theta HEBR mediated the MBSR treatment effect.
Conclusions:
Mindfulness meditation improves brain functions of attentional control and resting brain states reflective of internally oriented relaxation. However, interoceptive neural functions enhanced by MBSR appear to be a primary cerebral mechanism that improves symptoms of PTSD.
Keywords: EEG; Interoception; Meditation; Mindfulness; Post-Traumatic Stress Disorder; Treatment Mechanism.
PMID: 34688923 DOI: 10.1016/j.bpsc.2021.10.005
BACK
