A symposium was planned by the International Exchange Committee of the Japanese Society of Biofeedback Research during the COVID-19 pandemic. Three speakers each talked about the use of telemedicine/telehealth in their fields. The first speaker talked about the OnTrackNY team intervention for early stage schizophrenia and its use of telehealth, mentioning the great challenge clinicians face for online assessment and management of psychosis and elevated suicide risk. The second speaker talked about the sixty years’ history of the Japanese Antarctic Research Expedition, with its use of tele-communication systems, beginning in the early days of high frequency radio up to the newer INMARSAT and INTELSAT systems of today. Telemedicine has been implemented to assist medical doctors at Syowa Station, Antarctica to treat disease and injury of Wintering personnel. The third speaker talked about research done during his actual Wintering, and the use of online biofeedback for hypersensitivity to cold, and hypothesizes that the autonomic nervous system may be helping human adaptation to extreme conditions such as the cold environment of Antarctica. Telemedicine/telehealth can be an alternative and useful “non-contact” method during pandemics.

  [Purpose] The purpose of this study was to investigate the masseter muscle activity during meals in patients with bite clenching syndrome and normal subjects using a simple electromyograph. [Methods] The subjects were one healthy person who was not under dental treatment and one patient with Dental Disstress Syndrome. Recording electrodes were placed on the right masseter muscle, and electromyogram (EMG) was measured at four different times : a : maximum bite, b : minimum bite, c : during gum chewing, and d : during banana chewing. As a result, the average Root Mean Square (RMS) value of each was calculated. [Results] The mean RMS of healthy subjects was a : 1.21±0.21, b : 0.06±0.01, c : 0.44±0.20, d : 0.23±0.05 (μV), and that of patients was a : 3.35±0.38, b : 0.07±0.01, c : 1.14±0.26, d : 0.40±0.05 (μV). In the case of gum, the myoelectric amplitude decreased as the gum softened from solid to moist. In addition, the timing of biting was periodic and constant, indicating that the patient was able to chew the gum with saliva. On the contrary, the patient’s muscle activity showed that the bite force was not periodic and indefinite. Especially for chewing gum, the myoelectric amplitude increased with repeated chewing of food, indicating that the patient may not be able to grasp the appropriate bite force. [Discussion] The patient’s muscle activity is greater during food chewing, and the patient may not be able to grasp the appropriate bite force themself. If these sensory receptors are blocked due to disease, it is possible to compensate and relearn sensation by using visual feedback such as electromyography, auditory feedback. In the case of a disease, there is a possibility that compensation and sensory relearning can be achieved.

  [Introduction] Heart rate variability biofeedback (HRV-BF) has been clinically applied to both physical and psychological disorders. An HRV-BF study using rhythmical 0.1 Hz (6 times per minute) skeletal muscle tension (RSMT) instead of respiratiory approach has been reported in the past which seems to bring about the same resonance effect of the cardiovascular system. We devised a modified-RSMT-method, using a repetitive wrist dorsiflexion (grasping) with finger group flexion for 5 seconds, and wrist joint palmar, extension (releasing) with finger group extension for 5 seconds. Application of this method resulted in improvement of a patient with essential tremor. Consent for reporting of this study has been obtained from the patient, and there are no conflicts of interest to be disclosed.

  [Subject and method] The subject was a teenage woman who presented with essential tremor continuing for 8 months after a traffic accident. She was introduced to our Rehabilitation Department, at the time of scrutiny hospitalization in the Neurology Department. After we explained the aforementioned method, she sat in a chair, with her upper limbs placed on a desk. We taught the patient to repetitively “grasp” and “release”, by calling out at 5-second intervals, and had her practice for 5 minutes. The effect was judged by her actual writing (graphology) and video recording, and treatment continued for 4 days.

  [Results and discussion] The patient immediately felt a decrease in the amplitude of the essential tremor from the first intervention, and she also felt “calm”. On the 4th day (the day of her discharge), her head and lower limb’s symptoms had disappeared, and her graphological collapse was significantly improved. After her discharge, she practiced at home for 11 weeks. When she returned to the hospital on Day 78, she told us that although she felt a strong tremor at times, she felt the tremor decrease after her self-practice. We saw her tremor improve just by her sitting and relieving her tension. The modified-RSMT-method can be easily practiced, and may be applicable to a wide range of diseases.