Beyond isolation: preferred rates of oscillation, from fireflies to epilepsy.

The observed light synchronism that comes naturally to a variety of oscillatory systems includes not only fireflies flashing in unison (1), but a number of other organisms and cells that have a preferred rate of oscillation. The observed motion of analogous phenomena such as these and brain cells that emit electric signals in rhythm (beneficial or detrimental) indicated by the frequency tracings of an electroencephalogram may contain many unexpected symmetries. In the investigation of these symmetries light could reveal itself to be the critical interface.