The investigation of the perception of the position where the somatosensory information changes sharply with forward and backward leaning.

可以想象，站立前后方向的位置感知是基于体感信息随前倾和后倾的变化。为了澄清以下三个问题，本研究对11名受试者进行了研究。1)是否有可能准确地感知足压和肌肉活动随身体倾斜的急剧变化？2)当脚底某一特定部位冷却，使压力感觉不那么敏感时，对足压力和肌肉活动急剧变化的感知是如何变化的？3)通过冷却第一个脚趾或第一个跖骨头来减少压力感觉信息时，足底特定部位的压力强度感知如何变化？结果与讨论：所有受试者均能感知第一跖骨头压力的最大值，但无法感知第一趾压力的早期急剧增加，误读了后者的急剧增加。在对外展幻觉、股直肌和胫骨前肌活动的感知上，11名受试者中有8人误以为后者为前者的急剧增加。所得建议如下。后者第一趾压力和外展幻觉活动的急剧增加与第一跖头达到最大值后压力从第一跖头转移到第一趾有关。来自第一跖骨头压力的压力感觉强烈地参与了后者对第一趾压力急剧增加的感知。第一趾的压力感参与了后一种外展幻觉的急剧增加。在感知股直肌活动时，与足跟压力信息的关系存在个体差异。另一方面，在胫骨前肌也有一些。为了感知第一个脚趾压力的强度，来自第一个脚趾的压力信息在第一个脚趾压力上升的位置变得重要，而来自第一个跖骨头的压力信息在压力从第一个跖骨头转移到第一个脚趾的位置变得重要。为了感知第一跖骨头压力的强度，来自第一跖骨头从低到高的压力信息是重要的。少

It is conceivable that standing position in the antero-posterior direction is perceived based on the change of the somatosensory information with forward and backward leaning. To clarify the following three problems, this research was executed for 11 subjects. 1) Is it possible to perceive accurately a sharp change in foot pressure and muscle activity with the body leaning? 2) How does the perception of a sharp change in foot pressure and muscle activity vary when a specific part of foot sole is cooled to make the pressure sensation less sensitive? 3) How does the perception of pressure intensity in a specific part of foot sole vary when information of pressure sensation is reduced by cooling the first toe or the first metatarsal head? Results and discussion : All of the subjects were able to perceive the maximal value of the first metatarsal head pressure, but they were not able to perceive the early sharp increase of the first toe pressure, they mis-perceived the latter sharp increas … More e for the early one. In the perception of the activities of abductor hallucis, rectus femoris, and tibialis anterior, eight out of 11 subjects mis-perceived the latter sharp increase for the early one. The suggestions were obtained as follows. The latter sharp increase of the first toe pressure and abductor hallucis activity related to the pressure shifting from the first metatarsal head to the first toe after the first metatarsal head reaching the maximal value. The pressure sensation from the first metatarsal head pressure strongly took part in the perception of the latter sharp increase of the first toe pressure. The pressure sensation from the first toe took part in the latter sharp increase of abductor hallucis. There were individual variations of the relationship with pressure information from the heel in the perception of rectus femoris activity. On the other hand, there was a few in tibialis anterior. To perceive intensity of the first toe pressure, the pressure information from the first toe became important in a position where the first toe pressure rose, and the pressure information from the first metatarsal head became important in a position where the pressure shifted from the first metatarsal head to the first toe. To perceive intensity of the first metatarsal head pressure, the pressure information from the first metatarsal head ranging from low pressure to high was important. Less