440 HANDBOOK OF PHVSIOLOGV ^ NEUROPHVSIOLOCY 1 



f-C^OOSJ'/set: 



'■0,02°l%iz 



— Thermode temperature 

 Skin temperature 0. 5mm 



10 min 11 



Time t 



FIG. 7 Position of the warmtli and cold thresholds on the forearm at rectilinear temperature 

 changes of different directions and slopes (thermode area of 20 cm-). The slower the rate of change, 

 the more distant from the indifferent temperature (33.4°C) the thresholds lie. [From Hensel (42).] 



Zi 



29 



30 



31 32 33 3¥ 35 

 Temperature 9 



37 



31 "C 33 



FIG. 8- Position of warm and cold thresholds in relation to the rate of temperature change, dfl/d/, 

 and the temperature 9 of the skin. Broken lines, threshold sensation; solid line, distinct sensation. Initial 

 temperature in all experiments, 33.3°C. [From Hensel (42)-] 



