呼吸と舌運動との連関

The purposes of the present study were to examine whether there was a relationship between respiration movement and tongue movement, and to determine that the protrusion of the tongue was produced in the inspiration activity. The twelve adult rats were used in anaesthetized experimental condition. Respiration movement was examined in the way of recording the temperature of the expiration by the thermocouple sensor inserted in the trachea. Tongue movement, in the way of recording nerve impulses on the medial and lateral branches of hypoglossal nerve under oral cavity. Stimulation of the medial branch yields tongue protrusion, which stimulation of the lateral branch yields tongue retraction ln light anesthesia, the rhythmical discharges were generated on the medial branch, not on lateral branch. In spontaneous respiration, the rhythmical discharges were generated in about 170 msec before the inspiration movement. The rhythmical discharges were recorded also on vagus afferents in the inspiration movement. In artificial respiration, the cycle of the rhythmical discharges on the medial branch did not coincide with the cycle of respiration ln spontaneous respiration, the rhythmical discharges on the medial branch yields tongue protrusion that prevents the airway from the occlusion by dropping of tongue root in inspiration phase. It is supposed that the tongue protrusion coincided with inspiration is induced by normal rhythmical outputs of respiration center

日常食の性状と咀嚼様式

Many researches on relationships between physical properties of foods and masticatory movements deal with them to individual foods in experimental conditions. This study was done for effects of 10 different types of daily meal on masticatory patterns, such as the numbers of bringing food to mouth and chewing, the duration of taking a daily meal, the total duration of moving chopsticks, and on EMG activities of masticatory and swallowing muscles. Each daily meals had the following composition: boiled rice, noodles, bread and roll as principal food, and broiled fish, tempura and meat with potato, meat dish, ground meat rolled in cabbage leaves, stew, roast tofu, spaghetti mushroom as side dish, etc. The amount and the calorie were calculated on each daily food. EMGs were recorded simultaneously from eight parts as following: both temporal, both masseter, inferior orbicularis oris, one side of digastric and both sternohyoideus muscles. Five subjects varying in age fron1 22 to 26 years and weighing from 46 to 64 kg with both sexes took part in this study. The numbers of bringing food to mouth and chewing it are not many in the diet with bread or noodle compared with in the diet with rice, and in the soup without ingredients compared with that with it. The average values for bringing to mouth and chewing are 75.4 ± 12.3 times (min; 42, max; 115) and 679.6 ± 99.6 times (min; 354, max; 924). Integrated value of EMG is directly proportional to the chewing times and the duration time of taking a daily meal. EMGs produced the patterns with some characters in dropping to mouth, chewing and swallowing, and in case of each food. It is supposed that the diet with rice elevates the number and EWIG activities of chewing in comparison with the diet with another principal food