Mindfulness-based stress reduction (MBSR) improves PTSD symptoms more than an active control therapy in veterans, and this improvement is linked to changes in the brain's processing of bodily signals. Veterans with PTSD were randomly assigned to eight weeks of MBSR or present-centered group therapy. The MBSR group showed greater symptom reduction and increased frontal theta brain responses to heartbeats, a measure of interoception. Only these interoceptive neural changes statistically mediated the treatment effect, suggesting that enhanced brain processing of bodily sensations is a key mechanism behind MBSR's therapeutic benefit for PTSD.
A randomized clinical trial compared mindfulness-based stress reduction (MBSR) to present-centered group therapy in 98 veterans with PTSD. MBSR led to greater reductions in PTSD symptoms, increased spontaneous alpha brainwave power in posterior sites, stronger task-related frontal theta power, and enhanced frontal theta heartbeat-evoked brain responses. Only changes in frontal theta heartbeat-evoked responses mediated the treatment effect, with source-level analysis showing that theta changes in the anterior cingulate cortex, anterior insular cortex, and lateral prefrontal cortex predicted symptom improvement. The findings suggest that mindfulness meditation improves relaxation and attentional control, but enhanced interoceptive brain capacity appears to be the primary mechanism regulating emotional disturbances in PTSD.
Transcendental Meditation (TM), a mantra-based technique, appears to be an acceptable and effective treatment for veterans with posttraumatic stress disorder (PTSD). In a pilot study of 29 veterans (20.7% female), eight weeks of TM instruction led to reductions in PTSD symptoms, experiential avoidance, and depressive and somatic symptoms, along with increases in mindfulness and quality of life. These gains were maintained or improved at a two-month follow-up. Electroencephalography (EEG) showed increased low-frequency (1-7 Hz) spectral power during meditation states at posttreatment and follow-up, indicating TM-specific changes in brain state. The findings warrant further study of TM's outcomes and beneficial brain changes.