absolute thresholds were measured on 27 young ( ages 19 to 31 ) and 21 elderly ( ages 55 to 84 ) humans to six modes of cutaneous stimulation ( single ramp-and-hold skin indentations -- tactile , vibration at 40 and 250 hz , temperature increases and decreases , and noxious heat ) at two sites , the thenar eminence and the plantar foot .
C0230463
plantar
C0016504
foot