慢呼吸訓練早已被許多研究證實對於身體有許多益處，但比起一般的運動訓練，像是瑜珈、健身，慢呼吸訓練的人數相比之下沒有這麼多。那之所以不多的原因是有五個，使得新手很難持續訓練。慢呼吸訓練的過程很無趣、沒有任何回饋、需要花時間去感受效果、容易睡著以及容易分心。在過往的慢呼吸系統，絕大多數的研究都屬於臨床應用，並沒有去多次訓練來評估使用者對於系統的滿意程度以及提供一個較好的介面來讓使用者能夠持續訓練。所以我們決定製作一個具有慢呼吸訓練的多重回饋虛擬實境系統，並且搭配問卷調查以詢問使用者對於系統的滿意度用來解決以上五項問題。虛擬實境的場景中，有一個使用者具有自身臉部的人體模型，其畫面中的腹部會隨著現實中的腹部呼吸頻率而改變，當呼吸頻率越慢，使用者會在衣服上觀察到越紅越粗的線條，並且可以感受到溫度的改變，溫度改變是模擬呼吸訓練所帶來的熱感，藉此得知目前的呼吸狀況以調整自身的呼吸快慢。其結果得知，利用此系統比其沒有回饋的系統，在呼吸頻率的改善，趣味性、專注力的評估以及昏睡的情況，都有較好的表現。

Slow breathing training has been shown to be highly beneficial for human health, by many studies. However, there are five main reasons that discourage beginners from continuing their training. The traditional slow breathing training lacks feedback and is not engaging enough for participants to continue. Furthermore, it takes time for the subject to realize the benefits. Also, the participants get easily distracted and might even fall asleep during the training. Prior studies on slow breathing training were done in a clinical setting and most of them only had a single session each. Also, user’s satisfaction with the system and their feedback was not assessed to provide a better interface for them to continue training. To address the above challenges in traditional slow breathing training, we have designed a virtual reality (VR) system, with multimodal biofeedback, to enhance participation and to ensure that subjects continue to enjoy their training. In our VR system, the user can see a model with user’s own face. Abdominal movements can be perceived, in relation to their breathing rate, as the pressure sensor records it. While visualizing redder and thicker lines on the abdomen of the VR model, as their breathing rate is reduced, the participants can adjust their speed of breathing. Also, the tactile feedback from sensing body’s temperature, gives an immersive experience to the participant. This along with our collation of user experience with our questionnaire enable us to develop the system in a way that suits each individual. Such a multimodal system ensures that the individual continues to do slow breathing training and more importantly, enjoys the training process. Thus our new VR system, with multimodal biofeedback, excels in comparison to prior studies in addressing the challenges of traditional slow breathing training.

[1] Lutz, A., Slagter, H. A., Dunne, J. D., & Davidson, R. J. (2008). Attention regulation and monitoring in meditation. Trends in cognitive sciences, 12(4), 163-169.
[2] Kubota, Y., Sato, W., Toichi, M., Murai, T., Okada, T., Hayashi, A., & Sengoku, A. (2001). Frontal midline theta rhythm is correlated with cardiac autonomic activities during the performance of an attention demanding meditation procedure. Cognitive Brain Research, 11(2), 281-287.
[3] Schulze, E., Laudenslager, M., & Coussons‐Read, M. (2009). An exploration of the relationship between depressive symptoms and cortisol rhythms in Colorado ranchers. The Journal of Rural Health, 25(1), 109-113.
[4] Traustadottir, T., Bosch, P. R., & Matt, K. S. (2003). Gender differences in cardiovascular and hypothalamic-pituitary-adrenal axis responses to psychological stress in healthy older adult men and women. Stress, 6(2), 133-140.
[5] Chrousos, G. P. (2000). The role of stress and the hypothalamic–pituitary–adrenal axis in the pathogenesis of the metabolic syndrome: neuro-endocrine and target tissue-related causes. International Journal of Obesity, 24(S2), S50.
[6] Schure, M. B., Christopher, J., & Christopher, S. (2008). Mind–body medicine and the art of self‐care: teaching mindfulness to counseling students through yoga, meditation, and qigong. Journal of Counseling & Development, 86(1), 47-56.
[7] Griffith, J. M., Hasley, J. P., Liu, H., Severn, D. G., Conner, L. H., & Adler, L. E. (2008). Qigong stress reduction in hospital staff. The Journal of alternative and complementary medicine, 14(8), 939-945.
[8] Goyal, M., Singh, S., Sibinga, E. M., Gould, N. F., Rowland-Seymour, A., Sharma, R., ... & Ranasinghe, P. D. (2014). Meditation programs for psychological stress and well-being: a systematic review and meta-analysis. JAMA internal medicine, 174(3), 357-368.
[9] Mrazek, M. D., Smallwood, J., & Schooler, J. W. (2012). Mindfulness and mind-wandering: finding convergence through opposing constructs. Emotion, 12(3), 442.
[10] Mrazek, M. D., Franklin, M. S., Phillips, D. T., Baird, B., & Schooler, J. W. (2013). Mindfulness training improves working memory capacity and GRE performance while reducing mind wandering. Psychological science, 24(5), 776-781.
[11] Tang, Y. Y., Ma, Y., Wang, J., Fan, Y., Feng, S., Lu, Q., ... & Posner, M. I. (2007). Short-term meditation training improves attention and self-regulation. Proceedings of the National Academy of Sciences, 104(43), 17152-17156.
[12] Zeidan, F., Johnson, S. K., Gordon, N. S., & Goolkasian, P. (2010). Effects of brief and sham mindfulness meditation on mood and cardiovascular variables. The Journal of Alternative and Complementary Medicine, 16(8), 867-873.
[13] Frank, D. L., Khorshid, L., Kiffer, J. F., Moravec, C. S., & McKee, M. G. (2010). Biofeedback in medicine: who, when, why and how?. Mental health in family medicine, 7(2), 85.
[14] Hoover, J. C. (2000). U.S. Patent No. 6,162,183. Washington, DC: U.S. Patent and Trademark Office.
[15] Powers, M. B., & Emmelkamp, P. M. (2008). Virtual reality exposure therapy for anxiety disorders: A meta-analysis. Journal of anxiety disorders, 22(3), 561-569.
[16] Cho, B. H., Lee, J. M., Ku, J. H., Jang, D. P., Kim, J. S., Kim, I. Y., ... & Kim, S. I. (2002, March). Attention enhancement system using virtual reality and EEG biofeedback. In Proceedings IEEE Virtual Reality 2002 (pp. 156-163). IEEE.
[17] Kosunen, I., Salminen, M., Järvelä, S., Ruonala, A., Ravaja, N., & Jacucci, G. (2016, March). RelaWorld: neuroadaptive and immersive virtual reality meditation system. In Proceedings of the 21st International Conference on Intelligent User Interfaces (pp. 208-217). ACM.
[18] Gu, G., & Frasson, C. (2017, September). Virtual sophrologist: a virtual reality neurofeedback relaxation training system. In International Conference on Brain Function Assessment in Learning (pp. 176-185). Springer, Cham.
[19] Alaraj, A., Luciano, C. J., Bailey, D. P., Elsenousi, A., Roitberg, B. Z., Bernardo, A., ... & Charbel, F. T. (2015). Virtual reality cerebral aneurysm clipping simulation with real-time haptic feedback. Operative Neurosurgery, 11(1), 52-58.
[20] Crison, F., Lecuyer, A., d'Huart, D. M., Burkhardt, J. M., Michel, G., & Dautin, J. L. (2005, March). Virtual technical trainer: Learning how to use milling machines with multi-sensory feedback in virtual reality. In IEEE Proceedings. VR 2005. Virtual Reality, 2005. (pp. 139-145). IEEE.
[21] Vitense, H. S., Jacko, J. A., & Emery, V. K. (2003). Multimodal feedback: an assessment of performance and mental workload. Ergonomics, 46(1-3), 68-87.
[22] Wake, N., Sano, Y., Oya, R., Sumitani, M., Kumagaya, S. I., & Kuniyoshi, Y. (2015, April). Multimodal virtual reality platform for the rehabilitation of phantom limb pain. In 2015 7th International IEEE/EMBS Conference on Neural Engineering (NER) (pp. 787-790). IEEE.
[23] Navarro-Haro, M. V., López-del-Hoyo, Y., Campos, D., Linehan, M. M., Hoffman, H. G., García-Palacios, A., ... & García-Campayo, J. (2017). Meditation experts try Virtual Reality Mindfulness: A pilot study evaluation of the feasibility and acceptability of Virtual Reality to facilitate mindfulness practice in people attending a Mindfulness conference. PloS one, 12(11), e0187777.
[24] Shaw, C. D., Gromala, D., & Seay, A. F. (2007). The meditation chamber: Enacting autonomic senses. Proc. of ENACTIVE/07.
[25] Choo, A., & May, A. (2014, October). Virtual mindfulness meditation: Virtual reality and electroencephalography for health gamification. In 2014 IEEE Games Media Entertainment (pp. 1-3). IEEE.
[26] Takahashi, T., Murata, T., Hamada, T., Omori, M., Kosaka, H., Kikuchi, M., ... & Wada, Y. (2005). Changes in EEG and autonomic nervous activity during meditation and their association with personality traits. International Journal of Psychophysiology, 55(2), 199-207.
[27] Murata, T., Takahashi, T., Hamada, T., Omori, M., Kosaka, H., Yoshida, H., & Wada, Y. (2004). Individual trait anxiety levels characterizing the properties of Zen meditation. Neuropsychobiology, 50(2), 189-194.
[28] Faber, P. L., Lehmann, D., Gianotti, L. R. R., Kaelin, M., & Pascual-Marqui, R. D. (2004, April). Scalp and intracerebral (LORETA) theta and gamma EEG coherence in meditation. In meeting of the International Society for Neuronal Regulation, Winterthur, Switzerland.
[29] Litscher, G., Wenzel, G., Niederwieser, G., & Schwarz, G. (2001). Effects of QiGong on brain function. Neurological Research, 23(5), 501-505.
[30] Lee, M. S., Bae, B. H., Ryu, H., Sohn, J. H., Kim, S. Y., & Chung, H. T. (1997). Changes in alpha wave and state anxiety during ChunDoSunBup Qi-training in trainees with open eyes. The American journal of Chinese medicine, 25(03n04), 289-299.
[31] Aftanas, L. I., & Golosheikin, S. A. (2003). Changes in cortical activity in altered states of consciousness: the study of meditation by high-resolution EEG. Human Physiology, 29(2), 143-151.
[32] Arambula, P., Peper, E., Kawakami, M., & Gibney, K. H. (2001). The physiological correlates of Kundalini Yoga meditation: a study of a yoga master. Applied psychophysiology and biofeedback, 26(2), 147-153.
[33] Kamei, T., Toriumi, Y., Kimura, H., Kumano, H., Ohno, S., & Kimura, K. (2000). Decrease in serum cortisol during yoga exercise is correlated with alpha wave activation. Perceptual and motor skills, 90(3), 1027-1032.
[34] Hebert, R., & Tan, G. (2004, April). Enhanced EEG alpha phase synchrony in practitioners of the transcendental meditation technique. In meeting of the International Society for Neuronal Regulation, Winterthur, Switzerland.
[35] Travis, F., Tecce, J., Arenander, A., & Wallace, R. K. (2002). Patterns of EEG coherence, power, and contingent negative variation characterize the integration of transcendental and waking states. Biological psychology, 61(3), 293-319.
[36] Khare, K. C., & Nigam, S. K. (2000). A study of electroencephalogram in mediators. Indian Journal of Physiology and Pharmacology, 44(2), 173-178.
[37] Sackner, M. A., Gonzalez, H. F., Jenouri, G., & Rodriguez, M. (1984). Effects of abdominal and thoracic breathing on breathing pattern components in normal subjects and in patients with chronic obstructive pulmonary disease. American Review of Respiratory Disease, 130(4), 584-587.
[38] Lutz, A., Greischar, L. L., Rawlings, N. B., Ricard, M., & Davidson, R. J. (2004). Long-term meditators self-induce high-amplitude gamma synchrony during mental practice. Proceedings of the national Academy of Sciences, 101(46), 16369-16373.
[39] Lehmann, D., Faber, P. L., Achermann, P., Jeanmonod, D., Gianotti, L. R., & Pizzagalli, D. (2001). Brain sources of EEG gamma frequency during volitionally meditation-induced, altered states of consciousness, and experience of the self. Psychiatry Research: Neuroimaging, 108(2), 111-121.
[40] Ramirez, P. M., Desantis, D., & Opler, L. A. (2001). EEG biofeedback treatment of ADD: A viable alternative to traditional medical intervention?. Annals of the New York Academy of Sciences, 931(1), 342-358.
[41] Rosenfeld, J. P. (2000). An EEG biofeedback protocol for affective disorders. Clinical Electroencephalography, 31(1), 7-12.
[42] Tinius, T. P., & Tinius, K. A. (2000). Changes after EEG biofeedback and cognitive retraining in adults with mild traumatic brain injury and attention deficit hyperactivity disorder. Journal of Neurotherapy, 4(2), 27-44.
[43] Hsueh, J. J., Chen, T. S., Chen, J. J., & Shaw, F. Z. (2016). Neurofeedback training of EEG alpha rhythm enhances episodic and working memory. Human brain mapping, 37(7), 2662-2675.
[44] Zhang, Z., Wu, H., Wang, W., & Wang, B. (2010, October). A smartphone based respiratory biofeedback system. In 2010 3rd International Conference on Biomedical Engineering and Informatics (Vol. 2, pp. 717-720). IEEE.
[45] Pastor, M. C., Menéndez, F. J., Sanz, M. T., & Abad, E. V. (2008). The influence of respiration on biofeedback techniques. Applied Psychophysiology and Biofeedback, 33(1), 49-54.
[46] Uhlmann, C., & Fröscher, W. (2001). Biofeedback treatment in patients with refractory epilepsy: changes in depression and control orientation. Seizure, 10(1), 34-38.
[47] Nagai, Y., Goldstein, L. H., Fenwick, P. B., & Trimble, M. R. (2004). Clinical efficacy of galvanic skin response biofeedback training in reducing seizures in adult epilepsy: a preliminary randomized controlled study. Epilepsy & Behavior, 5(2), 216-223.
[48] Bersak, D., McDarby, G., Augenblick, N., McDarby, P., McDonnell, D., McDonald, B., & Karkun, R. (2001, September). Intelligent biofeedback using an immersive competitive environment. In Paper at the designing ubiquitous computing games workshop at UbiComp (pp. 1-6).
[49] Kumar, M., Pandey, D., & Shrivastva, P. (2016). Effect of GSR biofeedback relaxation training on blood glucose and anxiety level of type 2 diabetic patients. International Journal of Indian Psychology, 4(1).
[50] Jo, E., Lewis, K., Directo, D., Kim, M. J., & Dolezal, B. A. (2016). Validation of biofeedback wearables for photoplethysmographic heart rate tracking. Journal of sports science & medicine, 15(3), 540.
[51] Ahmad, Z., & Mong, T. C. (2016). Development of Portable Biofeedback Devices for Sport Applications. In Proceedings of the 2nd International Colloquium on Sports Science, Exercise, Engineering and Technology 2015 (ICoSSEET 2015) (pp. 55-66). Springer, Singapore.
[52] Yu, B., Funk, M., Hu, J., & Feijs, L. (2017, June). StressTree: A metaphorical visualization for biofeedback-assisted stress management. In Proceedings of the 2017 Conference on Designing Interactive Systems (pp. 333-337). ACM.
[53] Cahn, B. R., & Polich, J. (2006). Meditation states and traits: EEG, ERP, and neuroimaging studies. Psychological bulletin, 132(2), 180.
[54] Behrens, F., MacKeben, M., & Schröder-Preikschat, W. (2010). An improved algorithm for automatic detection of saccades in eye movement data and for calculating saccade parameters. Behavior research methods, 42(3), 701-708.
[55] Tong, J., Maruta, J., Heaton, K. J., Maule, A. L., & Ghajar, J. (2014). Adaptation of visual tracking synchronization after one night of sleep deprivation. Experimental brain research, 232(1), 121-131.
[56] Bolte, B., & Lappe, M. (2015). Subliminal reorientation and repositioning in immersive virtual environments using saccadic suppression. IEEE transactions on visualization and computer graphics, 21(4), 545-552.
[57] Zhuang, Y., Chen, L., Wang, X. S., & Lian, J. (2007, June). A weighted moving average-based approach for cleaning sensor data. In 27th International Conference on Distributed Computing Systems (ICDCS'07) (pp. 38-38). IEEE.
[58] Liang, S. F., Kuo, C. E., Lee, Y. C., Lin, W. C., Liu, Y. C., Chen, P. Y., ... & Shaw, F. Z. (2015). Development of an EOG-based automatic sleep-monitoring eye mask. IEEE Transactions on Instrumentation and Measurement, 64(11), 2977-2985.
[59] Lagopoulos, J., Xu, J., Rasmussen, I., Vik, A., Malhi, G. S., Eliassen, C. F., ... & Davanger, S. (2009). Increased theta and alpha EEG activity during nondirective meditation. The Journal of Alternative and Complementary Medicine, 15(11), 1187-1192.
[60] Zeier, H. (1984). Arousal reduction with biofeedback-supported respiratory meditation. Biofeedback and self-regulation, 9(4), 497-508.
[61] Tinga, A. M., Nyklíček, I., Jansen, M. P., de Back, T. T., & Louwerse, M. M. (2019). Respiratory biofeedback does not facilitate lowering arousal in meditation through virtual reality. Applied psychophysiology and biofeedback, 44(1), 51-59.
[62] Chiesa, A. (2009). Zen meditation: An integration of current evidence. The Journal of Alternative and Complementary Medicine, 15(5), 585-592.
[63] Wallace, R. K., Benson, H., & Wilson, A. F. (1971). A wakeful hypometabolic physiologic state. American Journal of Physiology-Legacy Content, 221(3), 795-799.
[64] Ghista, D. N., Nandagopal, D., Ramamurthi, B., Das, A., Mukherji, A., & Srinivasan, T. M. (1976). Physiological characterisation of the ‘meditative state’during intuitional practice (the Ananda Marga system of mediation) and its therapeutic value. Medical and Biological Engineering, 14(2), 209-214.
[65] Pan, W., Zhang, L., & Xia, Y. (1994). The difference in EEG theta waves between concentrative and non-concentrative qigong states--a power spectrum and topographic mapping study. Journal of traditional Chinese medicine= Chung i tsa chih ying wen pan, 14(3), 212-218.
[66] Travis, F., & Wallace, R. K. (1999). Autonomic and EEG patterns during eyes-closed rest and transcendental meditation (TM) practice: the basis for a neural model of TM practice. Consciousness and cognition, 8(3), 302-318.
[67] Joseph, C. N., Porta, C., Casucci, G., Casiraghi, N., Maffeis, M., Rossi, M., & Bernardi, L. (2005). Slow breathing improves arterial baroreflex sensitivity and decreases blood pressure in essential hypertension. Hypertension, 46(4), 714-718.
[68] Belman, M. J., Thomas, S. G., & Lewis, M. I. (1986). Resistive breathing training in patients with chronic obstructive pulmonary disease. Chest, 90(5), 662-669.
[69] Pal, G. K., & Velkumary, S. (2004). Effect of short-term practice of breathing exercises on autonomic functions in normal human volunteers. Indian Journal of Medical Research, 120(2), 115.
[70] Zautra, A. J., Fasman, R., Davis, M. C., & Arthur, D. (2010). The effects of slow breathing on affective responses to pain stimuli: an experimental study. Pain®, 149(1), 12-18.
[71] Wang, S. Z., Li, S., Xu, X. Y., Lin, G. P., Shao, L., Zhao, Y., & Wang, T. H. (2010). Effect of slow abdominal breathing combined with biofeedback on blood pressure and heart rate variability in prehypertension. The Journal of Alternative and Complementary Medicine, 16(10), 1039-1045.
[72] Mason, H., Vandoni, M., Debarbieri, G., Codrons, E., Ugargol, V., & Bernardi, L. (2013). Cardiovascular and respiratory effect of yogic slow breathing in the yoga beginner: what is the best approach?. Evidence-Based Complementary and Alternative Medicine, 2013.
[73] Sivakumar, G., Prabhu, K., Baliga, R., Pai, M. K., & Manjunatha, S. (2011). Acute effects of deep breathing for a short duration (2-10 minutes) on pulmonary functions in healthy young volunteers. Indian J Physiol Pharmacol, 55(2), 154-159.
[74] Jerath, R., Edry, J. W., Barnes, V. A., & Jerath, V. (2006). Physiology of long pranayamic breathing: neural respiratory elements may provide a mechanism that explains how slow deep breathing shifts the autonomic nervous system. Medical hypotheses, 67(3), 566-571.
[75] Brown, R. P., & Gerbarg, P. L. (2005). Sudarshan Kriya yogic breathing in the treatment of stress, anxiety, and depression: part I—neurophysiologic model. Journal of Alternative & Complementary Medicine, 11(1), 189-201.
[76] Radaelli, A., Raco, R., Perfetti, P., Viola, A., Azzellino, A., Signorini, M. G., & Ferrari, A. U. (2004). Effects of slow, controlled breathing on baroreceptor control of heart rate and blood pressure in healthy men. Journal of hypertension, 22(7), 1361-1370.
[77] Russo, M. A., Santarelli, D. M., & O’Rourke, D. (2017). The physiological effects of slow breathing in the healthy human. Breathe, 13(4), 298-309.
[78] Ma, X., Yue, Z. Q., Gong, Z. Q., Zhang, H., Duan, N. Y., Shi, Y. T., ... & Li, Y. F. (2017). The effect of diaphragmatic breathing on attention, negative affect and stress in healthy adults. Frontiers in psychology, 8, 874.
[79] Schleicher, R., Galley, N., Briest, S., & Galley, L. (2008). Blinks and saccades as indicators of fatigue in sleepiness warnings: looking tired?. Ergonomics, 51(7), 982-1010.
[80] Caffier, P. P., Erdmann, U., & Ullsperger, P. (2003). Experimental evaluation of eye-blink parameters as a drowsiness measure. European journal of applied physiology, 89(3-4), 319-325.
[81] Amihai, I., & Kozhevnikov, M. (2015). The influence of Buddhist meditation traditions on the autonomic system and attention. BioMed research international, 2015.
[82] MCQE. (2019). Astronomy VR. Retrieved from https://store.steampowered.com/app/1062690/Astronomy_VR/
[83] PaleBlue XYZ. (2018). Number Hunt. Retrieved from https://store.steampowered.com/app/851770/Number_Hunt/
[84] STRIVR. (2017). 30 Percentage Point Increase In Recall Of Topics After Using STRIVR. Retrieved from https://www.strivr.com/30-percent-increase-in-recall/
[85] EON Reality. (2015) EON Sports VR Project OPS with Jason Giambi. Retrieved from https://www.youtube.com/watch?v=rZw-7tfvWWE
[86] Balfour Beatty. (2016) Virtual Reality is shaping the future of construction. Retrieved from https://www.youtube.com/watch?v=R4gWpXuPAXo
[87] Ford Motor Company. (2012). Virtual Reality at Ford Motor Company. Retrieved from https://www.youtube.com/watch?v=zmeR-u-DioE
[88] TAFI AVATARS. (2017) MCS Male. Retrieved from https://assetstore.unity.com/packages/3d/characters/humanoids/mcs-male-45805.
[89] FaceGen. (2012) FaceGen Modeller. Retrieved from https://www.youtube.com/watch?v=tRVq8Tmf8KY.
[90] NeuroSky. (2015) MindWave Mobile. Retrieved from https://store.neurosky.com/