Hiroyuki KAJIMOTO (梶本 裕之)

Dystonia is a movement disorder characterized by sustained or intermittent muscle contractions that result in abnormal, often repetitive movements, postures, or both. Zolpidem has been reported as an effective treatment for dystonia. We describe the case of a 24-year-old male long-distance runner with dystonia who successfully resumed competitive running by using a combination of a hanger reflex-inducing device and treatment with zolpidem. The patient presented with a sensation of weakness in his right foot while running. Video analysis of the running gait confirmed internal to external rotation of the right lower limb. At treatment initiation, a wrist-type hanger reflex induction device was adapted for use on the right ankle. At three months, the patient was able to run up to 20 km without any symptoms. He was subsequently prescribed zolpidem, which ultimately helped him to complete a full marathon without experiencing any symptoms. This report suggests that the combination of zolpidem and a hanger reflex device may be a promising, noninvasive treatment option for runner's dystonia.

This study proposes a method to present pure low-frequency vibration sensations to the face that cannot be presented by small commercially available vibrators. The core innovation lies in utilizing an amplitude modulation technique with a carrier frequency of approximately 200 Hz. Due to the absence of Pacinian corpuscles in the facial region—receptors responsible for detecting high-frequency vibrations around 200 Hz—only the original low-frequency signal is perceived. Three experiments were conducted. Experiments 1 and 2 were performed on the forehead to confirm that the proposed amplitude modulation method could produce the desired low-frequency perception and to evaluate the subjective quality of the vibration. The results suggested that the proposed method could produce the perception of desired pure low-frequency vibration when applied to the forehead. In Experiment 3, the proposed method was applied to the whole face, and its range of applicability was explored. The results indicated that the original low-frequency vibration was clearly perceptible around the eyes, cheeks, and lower lip area.