“…Earlier experiments, focusing on the consequences of short-term exposure to either simulated or actual road situations, found that driving behavior is often accompanied by elevated heart rate (Simonson, Baker, Burns, Keiper, Schmitt, & Stackhouse, 1968;Taggart, Gibbon, & Somerville, 1969;Hunt & May, Note 1), skin conductance (Heimstra, 1970;Hulbert, 1957), and catecholamine secretion (Bellet, Roman, & Kostis, 1969). Although these studies clearly document the physiological arousal sometimes associated with driving, they provide no direct evidence regarding the psychological, physical, and behavioral residues of long-term exposure to traffic congestion.…”