A single 90-minute session of Floatation-REST, which minimizes sensory input, reduces resting-state functional connectivity within and between posterior hubs of the default-mode network and somatomotor cortices extending into the posterior insula. A control condition of resting in a zero-gravity chair produced a similar pattern of reduced connectivity. The findings suggest that reducing nervous system stimulation is reflected by decreased connectivity in brain networks that construct and map the sense of self.
A nonrandomized, single-arm study tested whether typically developing adolescents could learn to self-regulate the posterior cingulate cortex (PCC) using real-time functional MRI neurofeedback during mindfulness training. Thirty-four adolescents (mean age 15; 14 females) completed the task across neurofeedback and non-neurofeedback runs. Neurofeedback runs showed significantly decreased PCC activity during the Focus-on-Breath condition compared with Describe (z = -2.38 to -6.27). State awareness of physical sensations increased after neurofeedback and was maintained at 1-week follow-up (Cohen's d = 0.69). The findings demonstrate feasibility and tolerability of this approach in healthy adolescents and replicate the role of the PCC in mindfulness.