Finger NzGmbness in Very Cold Winds

T HE WPAIRMENT OF TOUCH by bitterly cold winds is an interesting phenome-non known to everyone. But it is less obvious that this effect can be put to work to analyze the results of changes in a cold environment. The main purpose of this research has been to discover whether a simple and convenient way of obtaining a reliable measure of numbness could be found for use under field conditions in the sub-Arctic. The second aim has been to determine whether any such biological index of numbness could assess the effects of the two main physical factors in wind chill-the effects of the atmospheric air temperature and wind speed. A biological measure of this kind has clearly some meaning in terms of human ability when-ever men must work with their bare hands in very cold atmospheres. The very tasks for which gloves have to be removed are those that need good manual dexterity, and accurate finger movements often depend on good touch sensitivity, particularly when vision cannot guide the hands at the same time. METHODS Thirty-five volunteers were studied in these tests, which were undertaken a