DOI: 10.5255/ukda-sn-856228
title: Perceived Threats and 'Stampedes': A Relational Model of Collective Fear Responses, 2020-2023

description: 1, Oxford Street False Alarm, 24th November 2017 Collective false alarm incidents, where crowds of people flee from what they think is a shooter or similar hostile threat, are politically, socially, and psychologically impactful. These incidents have been neglected by researchers, despite an upsurge in them in recent years. False alarms seem anomalous, as the usual public response to warnings of an emergency (such as a fire alarm) is to discount them. A first question is: under what conditions does a crowd perceive an ambiguous signal as a hostile threat, and what are the social processes involved? False alarm flight incidents have been used rhetorically to suggest that crowds are prone to panic, even though the concept has been largely discredited across the social sciences as an explanation for collective behaviour in real emergency events. Yet there is a lack of research evidence into how people actually behave in false alarms. Therefore a second question is what do people actually do and why? To examine the usefulness of a number of social-cognitive models (signal detection, social appraisal, social identity) in answering these questions, we interviewed 39 people who were involved in the false alarm incident in Oxford Street, London, on Black Friday 2017. In this event, thousands of people over an area of over one square kilometre ran and many hid from what they thought was a terrorist attack. Thematic analysis of the transcripts suggested the following pattern of behaviour and experience. First, there had been a large number of genuine terrorist attacks in London and other areas of the UK and Europe that same year, and for many people this fact operated as a framing through which ambiguous signals (including alarms and banging noises) were interpreted. People were also aware that parts of London were vulnerable to such attacks. In short, using the immediate historical context as a relevant reference point meant that ‘we’ (i.e., people on Oxford Street) were a possible target for a further terrorist attack. Second, there appeared to be a social appraisal process whereby the sight of others’ emotions and repeated (flight) behaviour added to the accumulating evidence of a hostile threat. Within this, the appearance of armed police offered only partial reassurance, as it added to the impression that an attack was in progress. In many cases, people’s interpretation was not immediate but (similar to the usual pattern of discounting emergency signals) developed gradually and only after repeated and separate pieces of ‘evidence’. The messages some received (by phone, social media, or shouts in the street), stating that there was a terrorist attack, contributed further to the evidence base. Third, in terms of behaviour, while half of the participants reported running, others walked, or delayed their self-evacuation. A large number hid. While there were a number of instances of supportive behaviour, particularly in pockets (e.g. those sheltering together), this wasn’t always the case, and there were also instances of pushing and trampling. Rather than the common fate that arises in those emergencies when there is a clear and well-defined threat, in this case there was a fragmented experience across the crowd as whole, and so a lack of shared social identity. Our analysis suggests a new way of thinking about collective responses to perceived hostile threats, and has implications for how the authorities communicate with and prepare the public in case of such emergencies. 2, Virtual Reality experiments: Social influence in collective responses to perceived threats Collective flight incidents, often referred to as ‘stampedes’, have been and still are mistakenly associated with self-interest and panic. However, a growing body of research using post-incident analysis of crowd flights strongly suggest that flight phenomena are underlaid by complex psychological processes involving social identity, shared fate, and appraisal. A series of 5 experiments were undertaken to further our understanding of the mechanisms underlying collective responses to perceived threats. We used virtual reality technology to create realistic scenarios of an urban environment where a potential threat is triggered and the crowd reacts to it. In the first experimental series (2 studies, N ~ 800), we used animation as a vignette and measured participants’ reported perception of threat, perception of other crowd members, and intentions to run in response to a potential threatening noise, and a crowd in the animation that either ran or ignored that noise. Consistent with the social identity approach, the self-reported data indicate a key role of shared social identity amongst crowd members in explaining collective behaviours. The shared experience of facing and responding to a potential threat brought people together and increased shared social identification with other crowd members, especially when their response was consistent with the situation. Moreover, and challenging a ‘contagion’ model of collective behaviour in evacuations, the behaviour to run was mediated by the perceived threat, shared fate and shared social identity with other crowd members. In the second experimental series (3 studies, N ~ 1200) participants were immersed in an online desktop version of the virtual reality scenarios, being able to decide how and where to move, at what speed, etc. Across experiments, we manipulated the presence or absence of the noise triggering the crowd behaviour, the terror threat level, and the crowd behaviour. The behavioural data showed social influence processes, whereby participants were more likely to run away from a potential threat when other crowd members fled. Importantly, they were not equally influenced by all crowd members. Instead, they relied more on those with whom they identified (i.e, ingroup members) for guidance, both when appraising the situation and deciding how to act. These results provide empirical evidence against a ‘contagion’ model of collective response to threat, by showing that several factors interact with each other to impact participants’ running behaviour, and the extent to which they are likely to follow other crowd members. Moreover, they highlight the importance of social-psychological variables, and in particular of the social identity approach, to improve models of collective behaviours and inform the intervention of emergency services.