Resting-State Connectivity and Neuroimaging of Prefrontal Cortex Activity During a Block-Design Yoga Asana Practice Using fNIRS

This study aimed to use functional near-infrared spectroscopy (fNIRS) mobile neuroimaging technology to examine changes in prefrontal cortex (PFC) activity before, during, and after yoga asana (physical yoga postures). A total of 27 healthy adults participated in a 23 min yoga asana session using a block design. Before and after the sequence, participants completed two 6 min, task-independent resting states. PFC activity was continuously recorded using the fNIRS instrument, positioned on the frontal area of the skull. The session included a control posture alternating with three active postures. Each active posture was held for 30 s, followed by a 25-30 s control posture interval, and repeated eight times. This block design resulted in 25 control posture intervals and 24 repetitions of each active posture. Analysis included preprocessing of raw fNIRS data to calculate concentrations of oxyhemoglobin (HbO) and deoxyhemoglobin (HbR), motion artifact correction, and statistical evaluation using ANOVA with Bonferroni corrections. Connectivity analyses examined interhemispheric and intrahemispheric correlations in the prefrontal cortex. In conclusion, this study demonstrates the utility of fNIRS in real-world, movement-based contexts and provides neurological insights into the effects of yoga asana.