Spatial Discrimination of Cutaneous Warmth

One experiment explored capacity to discriminate between a single field of warmth and two fields of warmth separated from each other by various distances. Discriminability, measured by d', increased with both interfield distance and level of irradiance. Spatial acuity was poor at low levels of stimulation and showed only modest improvement with increases in level of irradiance. Another experiment showed that irradiation of the ventral surface of the torso is sometimes confused with irradiation of the dorsal surface. Such gross errors of localization did not occur in the tactile sense.