Individual Variations of Rhythms in Morning and Evening Types with Special Emphasis on Seasonal Differences

摘要: Publisher Summary This chapter presents details related to individual variations of rhythms in morning and evening types with special emphasis on season differences. The focuses human rhythm patterns their modification by the diurnal type and, thus, relates a respectable Scandinavian tradition. In search for factors that might influence time structure individual, measurable biological characteristics such as phase position, amplitude, waveform, social, environmental sources have been proposed. Based circadian studies, Kerkhof concluded morningness–eveningness dimension is most important factor associated reliable interindividual Significant group differences concern mainly fatigability sleep items but also sadness cortisol. Findings suggest including typology chronobiological especially those focusing seasonal concerns, promising area research, implications mood disorders providing new insights into mechanisms relating system man.