S85-26571 (Feb 1985) --- Wearing a special collar, Millie Hughes-Fulford, payload specialist, practices medical test operations scheduled for the Spacelab Life Sciences (SLS-1) mission. Robert Ward Phillips, backup payload specialist, looks on. The collar, called the baroflex neck pressure chamber, is designed to stimulate the bioceptors in the carotid artery, one of the two main arteries that supply blood to the head.