Autoregulation of skin temperature with feedback-assisted relaxation of the target limb, and controlled variation in local air temperature.

The primary aim of this study was to determine whether feed-back-assisted skin temperature regulation can be demonstrated when skeletomuscular mediation, in the form of altered local EMG activity, is prevented. A second aim was to determine whether the success of such regulation is affected by the basal temperature of the skin. 30 adult subjects were asked to increase or decrease the temperature of the index finger of the dominant hand, while the local musculature was kept in a relaxed state using EMG feedback. The local ambient air temperature surrounding the limb was set at either 10 degrees C, 24 degrees C, or 38 degrees C, resulting in large differences in basal skin temperature. Subjects were successful at both increasing and decreasing skin temperature while maintaining an integrated EMG output below 75 muV in the target limb. The magnitude of change, much smaller than those commonly reported in this field, did not vary across the air temperature levels, indicating that skin temperature autoregulation under these conditions does not conform to the law of initial value. It was concluded that autoregulation of skin temperature can be demonstrated in a virtually flaccid limb, and that the amount of temperature change achieved is not a function of basal skin temperature.