ABSTRACT
In 1885, Gowers was the –rst to report that the occurrence of epileptic seizures is not entirely random. He classi–ed patients into three groups based on the distribution of –ts over the day: diurnal, nocturnal, and diffuse (Gowers 1885). Later, it was observed how diurnal seizures cluster at certain times of the day, i.e., upon awakening and in the late afternoon, and how nocturnal seizures tend to occur mainly at bedtime and the hours before awakening (Grif–ths et al. 1938; Langdon-Down et al. 1929). These observations, that seizures may occur in patterns depending on the pathophysiology of the epileptic syndrome, have also been con–rmed in more recent studies (Milton et al. 1987; Quigg et al. 1998b; Tauboll et al. 1991). The reason for these seizure patterns is not well understood. A hypothesis is that the circadian clock plays a signi–cant role. The interaction between circadian rhythmicity and epilepsy has been studied; however, still relatively little is known (Hofstra et al. 2009).
