Social influence in the crowd: Attitudinal and behavioural effects of de‐individuation in conditions of high and low group salience*

The study described here uses the social identity framework suggested by Tajfel and Turner to argue that de-individuation works by altering the salience of personal vs. social identity. Seventy students from science and 38 students from social science faculties were shown a film presenting arguments for and against vivisection, at the end of which they were told that science students had a pro- and social science students an anti-vivisection norm. Subjects were then told that they were being examined either as members of their faculty group or as individual students. They were either de-individuated or individuated. They were required to fill in an attitude questionnaire and to complete three quasi-behavioural measures. It was predicted that the group condition should increase salience of social identity and adherence to the group norm. It was also predicted that de-individuation in the group condition would further increase salience and hence normative behaviour, while in the individual condition de-individuation would decrease salience and hence normative behaviour. The first prediction was upheld on all the measures, and the second was partially confirmed.