The effect of partial pressure on upper extremity upon psychological characteristics

Abstract

To investigate the appropriate method to design the clothing needed to pressurize the human body, the effect of partial pressure on the upper extremities with respect to psychological characteristics were studied. Seven female students served as subjects. Results were as follows. (1) The mean distance of 2 areas with just noticeable differences was about 4 cm in all regions of the upper extremities regardless of pressure (below 60 mmHg) (2) Pressure sensation varied with the area where the pressure was applied. In the case of calculated pressure [pressure per unit area (g/cm2) x width of cuff (cm)], the pressure sensation obtained by a wide pressure area (4 cm or 7 cm in width) was small as compaired to a narrow pressured area (1 cm in width) against the same calculated pressure. Pressure sensation obtained between 4 cm and 7 cm in width was not significant. In the case of net pressure [pressure per unit area (g/cm2)], however, the propotion of the increase of pressure sensation to the ascent of pressure in the pressure area of 7 cm in width was large as compaired to thoseof 1 cm and 4 cm in width. It was supposed that if the pressure was applied at 4 cm in width to the upper extremity, the pressure sensation might be alleviated. (3) The pressure sensation in the upperarm was more sensitive than in forearm especially at high pressure (60 mmHg). Moreover, the pressure sensation in the forearm decreased when the pressure was applied to the upperarm. (4) Psychological distances between adjective words indicating pressure sensation were alrnost at the same interval in both the upperarm and forearm, but the pressure obtaining the same adjective words was smaller in the upperarm than in the forearm.