Is the startle reaction an emotion?

In this study, we examined startle reactions in which the subjects did and did not know when a blank pistol would be fired. In addition, we asked subjects to suppress their startle response and to simulate a startle when there was no gunshot. Detailed measurement of facial muscular actions supported most of the findings reported by Landis and Hunt (1939), but our findings suggested that startle be considered a reflex not an emotion. The findings are considered in terms of current disagreements about exactly what constitutes an emotion, including the argument between Zajonc (1980) and Lazarus (1984) about the role of appraisal.