Comparability of skin temperatures from three sites on the hand.

Skin temperature from three recording sites (web dorsum and two digital sites) on one hand were compared over a 30-minute period during which room temperature was raised from 66 degrees to 80 degrees F causing skin temperatures to range from 78.5 degrees to 92.3 degrees F. The web dorsum remained significantly warmer than either digital site at the lowest skin temperatures; no significant inter-site differences were seen as skin temperature gradually increased. These findings imply that none of the three sites is more advantageous than the others when recording hand temperature values around or above 85 degrees F. However, at the lower levels of skin temperature, there is a "floor" below which the web dorsum is no longer a sensitive indicator. More generally, basic data of this type provide a necessary but often absent foundation for routine practice of clinical biofeedback.