Do groups always inhibit individuals responses to potential emergencies?

Previous studies of bystander intervention in emergencies have found that an individual is more likely to intervene if he witnesses the emergency alone than as a member of a group. The present study qualifies this general finding in the framework of group communication processes. Pairs of subjects working on a task overheard a loud crash in an adjoining room. Some pairs of subjects were seated in a pattern that facilitated the visual communication exchanges that naturally occur when a noisy event takes place and others were seated so as to block these communications. When the emergency occurred, groups which could exchange reactions were not reliably less likely to respond than were a third group of subjects who faced the emergency alone. The blocked communications groups tended not to respond and responded significantly less than the other two conditions. These results were interpreted as supporting the hypothesis that a group of people who witness an ambiguous event interact to arrive at a definition or interpretation of it, which then guides each member's reactions to the event.