Aim: The aim of the study was to investigate the effects of high intensity IMT on specific areas in functional magnetic resonance (fMRI) compared with sham IMT. Methods: 26 healthy participants randomly assigned two groups as intervention (n=14) and sham (n=12). The intervention group received IMT at 60% of maximal inspiratory pressure (MIP). The sham group received IMT at 15% of MIP. Both groups trained for 30 minutes/day, 5 days/week, for 8 weeks. Groups underwent RS-fMRI before and after the treatment. Resting state networks differences were investigated. Brain resting state networks, seed based connectivity (SBC) was applied to the data which characterizes the connectivity patterns with a pre-defined seed. SBC was performed for Anterior Cingulate Cortex (ACC), bilateral insula and default mode network (DMN) connectivities with the other regions of the brain. Results: The intervention group showed more ACC, insula and DMN connectivity changed than sham group (Figure). DMN showed more connectivity with L insula, bilateral inferior and R superior frontal gyrus, L inferior occipital gyrus in intervention group. The MIP (132.4±31.7 vs. 105.6±25.9 cmH2O) was significantly different after IMT.
Conclusion: These differences in brain activity and connectivity may improve in ventilatory perception and integral within the attention and processing of interoceptive signals related to breathing with high intensity IMT.