People who use flotation REST (lying in a warm saltwater tank) tend to be physically active and report moderately above-average mindfulness, yet also more often report depression, daily anxiety, sleep disturbance, and muscle soreness compared with the general US population. Alcohol abstinence rates did not differ. The findings come from a cross-sectional survey of 61 adult flotation users recruited online and from a flotation center in the southwestern US. Because the study lacked pre-floating baseline measures, these differences reflect current status, not changes caused by flotation.
Mindfulness-Based Stress Reduction (MBSR) appears to influence brain function more than structure, with consistent enhancement of activity and connectivity in networks that support emotion regulation, self-referential processing, and attention. A narrative review of 27 studies (9 structural MRI, 10 neural activation, 11 functional connectivity) found that structural MRI findings were inconsistent, with most studies reporting no significant gray matter changes, though small studies noted modest increases in hippocampal and amygdala volume. In contrast, fMRI consistently demonstrated functional changes, including increased activity in the superior parietal lobule, posterior cingulate cortex, and prefrontal regions, and enhanced coupling between the medial prefrontal cortex and amygdala. Findings suggest improved top-down regulation of emotion, though study heterogeneity limits conclusions.