Neurological Evidence of Diverse Self-Help Breathing Trainings with Virtual Reality and Bio-Feedback Assistance

Resting state is a mental state and a research paradigm that people do nothing and idle as much as possible to show their baseline neuro signals. In this task, we instructed participants to rest with their eyes opened for 6 minutes. The VR environment of blue sky and swaying meadow was presented to the participants throughout this task.

Mindful breathing is a state that people focus on their inner sensation. In this task, the meadow's motion in the VR environment corresponded to the participants' inhalation and exhalation, as detected by the respiration belt. The participants were instructed to focus mentally on their bodily sensations as they breathed, with the meadow's sway as a visual cue.

Guided breathing refers to the breath training technique that trainees are guided to inhale and exhale according to a fixed tempo. In this task, meadow swayed in a fixed tempo of 4 seconds back and 6 seconds forth. The participants were instructed to synchronize their inhalation with the meadow's backward motion (lasting 4 seconds) and their exhalation with its forward motion (lasting 6 seconds).

Breath counting refers to the breath training technique that trainees mentally count the numbers of breath cycles they have finished in a certain period of time. In this task, similar to the mindful breathing task, the meadow's motion was synchronized with the participants' breathing patterns. During the 6 minutes, we instructed the participants to breathe naturally and mentally count their breathing cycles.