Effects of 3D virtual reality motionless imagery training program with an avatar.

The present study aimed to explore the effects of motionless imagery training with an avatar in virtual reality (VR) on emotion, cognition, and physiological response changes in healthy adults. Participants were 30 healthy adults aged between 19 and 35 years. All participants were randomly divided into the experimental group (n = 18), which executed the imagery training with an avatar in VR, or the control group (n = 12), which merely experienced the VR without an avatar. Both groups underwent the intervention, a 20-min session, 3 times a week for 6 weeks. VR experience questionnaires and physiological response changes were measured at pre- and post-test and emotional states and cognition tests were measured at pre-, post-, and follow-up test. The experimental group showed no significant changes in the Presence Questionnaire (PQ) and the Simulator Sickness Questionnaire (SSQ) after the intervention while the control group showed a significant decrease in the PQ after the intervention. In all emotional states, there were no significant differences in the interaction between times and groups. A significant main effect of time was revealed in all cognition tests except the delayed recall and the delayed recognition in K-Auditory Verbal Learning Test (K-AVLT). In physiological response changes, the experimental group showed significant improvements in the electromyogram (EMG) at rectus femoris on the left side after the intervention. Thus, imagery training with an avatar in VR can be considered to be effective for enhancements of cognitions and physiological response changes.