[Factors brought on by migraine].

Migraine is a paroxysmic abnormality in which asymtomatic periods alternate with the appearance of attacks. Such attacks are the end result of a chain of events leading on to the acute clinical syndrome. Amongst those phenomena which occur in the days prior to the attack starting, the factors which bring such attacks on have been widely studied by a great number of researchers. Identifying these initiating factors is a fundamental preventive element and looking into the behavioural mechanisms of such factors could prove useful in clarifying the pathogenic mechanisms of migraine. In the present study we review most of the works which have sought to identify these factors concerning the development of attacks and to work out their behavioural patterns.