François Sirois' influential paradigm for diagnosing episodes of epidemic hysteria is discussed. The part of his schema addressing the large diffuse outbreak should be eliminated as it does not possess characteristic features of mass hysteria and overlooks the potential social, cultural, political, ritualistic and institutional patterning of collective behavior. A case study involving the collective delusion of phantom rockets over Sweden during 1946 illustrates the complexities of such episodes.
An alarm about suspected toxic gas leakage was raised in a primary school. All the students were evacuated by the staff and the community to a district hospital in Teluk Intan, Perak, about 8 km from the school. Sixty-four primary students from the school, four secondary school students and a student’s mother, who was near the school were all examined by a team of medical officers: Perceptions and records of the incidence from the students, staff and medical officers were recorded and examined by the author who visited the school and the hospital after the incidence. Psychosomatic symptoms related to anxiety attack were predominant There was no evidence of any gas leak. Symptomatic management was given by the medical officers. The psychogenic aetiology of the subsequent physical symptoms and behaviour, and the difference from epidemic hysteria are discussed.
In the original particle swarm optimisation (PSO) algorithm, the particles' velocities and positions are updated after the whole swarm performance is evaluated. This algorithm is also known as synchronous PSO (S-PSO). The strength of this update method is in the exploitation of the information. Asynchronous update PSO (A-PSO) has been proposed as an alternative to S-PSO. A particle in A-PSO updates its velocity and position as soon as its own performance has been evaluated. Hence, particles are updated using partial information, leading to stronger exploration. In this paper, we attempt to improve PSO by merging both update methods to utilise the strengths of both methods. The proposed synchronous-asynchronous PSO (SA-PSO) algorithm divides the particles into smaller groups. The best member of a group and the swarm's best are chosen to lead the search. Members within a group are updated synchronously, while the groups themselves are asynchronously updated. Five well-known unimodal functions, four multimodal functions, and a real world optimisation problem are used to study the performance of SA-PSO, which is compared with the performances of S-PSO and A-PSO. The results are statistically analysed and show that the proposed SA-PSO has performed consistently well.
This discussion of an episode of mass hysteria in a Malay college in West Malaysia examines stress and conflict in relation to the interpretive process within a specific social setting. Unlike previous studies, which conceptualize mass hysteria as a cathartic response to accumulated stress, the present study treats stress as a matter of definition in a specific sociocultural context rather than as an objective given from which predictions can be made. Objections are raised to the logic of explanations that attribute mass hysteria to environmental stress. What is of concern is how meanings are assigned to events that are experienced as stressful, how participants and observers explain these events, and the consequences that follow from their interpretations.
This study questions the widely held assumption that the phenomenon known as mass psychogenic illness (MPI) exists per se in nature as a psychiatric disorder. Most MPI studies are problematical, being descriptive, retrospective investigations of specific incidents which conform to a set of pre-existing symptom criteria that are used to determine the presence of collective psychosomatic illness. Diagnoses are based upon subjective, ambiguous categories that reflect stereotypes of female normality which assume the presence of a transcultural disease or disorder entity, underemphasizing or ignoring the significance of episodes as culturally conditioned roles of social action. Examples of this bias include the mislabelling of dancing manias, tarantism and demonopathy in Europe since the Middle Ages as culture-specific variants of MPI. While 'victims' are typified as mentally disturbed females possessing abnormal personality characteristics who are exhibiting cathartic reactions to stress, it is argued that episodes may involve normal, rational people who possess unfamiliar conduct codes, world-views and political agendas that differ significantly from those of Western-trained investigators who often judge these illness behaviours independent of their local context and meanings.