Periodic Phenomena in Affective Illness with Special Reference to Annual Cycles

Abstract

Periodic phenomena, i.e., rhythms consisting of regular cycles, can be observed in nature at various frequencies, from the atomic to the cosmic level. Such phenomena in living organisms form the objects of chronobiology (Aschoff 1981a; Hekkens et al. 1988) which, in romantic medicine, was consequently labeled as “periodology” (Baumgarten Crusius 1836). Chronomedicine, a branch of chronobiology, deals with regular, or almost regular, cycles of pathological processes and of the organism’s reactivity to noxious or therapeutic agents (Reinberg and Smolensky 1983). In psychiatry, periodic phenomena in affective illness constitute the focal point of this kind of research (Wehr and Goodwin 1981, 1983). Recurrent forms of the disorder were formerly described as “periodic psychoses” (periodic mania, periodic melancholia, and periodic cyclic psychosis or circular insanity with alternations of mania and depression) by some authors (e.g., Kirn 1878; Kraepelin 1883), although, in the majority of cases subsumed under this term, the period, i.e., the length of the cycles (time elapsed from the onset of one episode to the next), varied considerably (see Slater 1938; Eastwood and Peter 1989). The term was later on extended to include psychoses which did not belong to the group of affective illness (e.g., Pilcz 1901; Hatotani and Nomura 1983), above all the so-called periodic catatonias (Müller 1900; Gjessing and Gjessing 1961; Gjessing 1974); yet still recurrent forms of mania, depression, and their combinations were regarded as the core disorders of this type of insanity. It is beyond any doubt that, indeed, periodic phenomena in the sense of (almost) regular cycles can be observed in affective illness much more frequently than in any other form of mental disorder (see Menninger-Lerchenthal 1960; Richter 1965).