EFFECTS OF AGING ON MORNINGNESS-EVENINGNESS AND SLEEP HABITS IN KOREAN AND JAPANESE WORKERS

The Morningness-Eveningness Questionnaire and Life Habits Inventory we re given to Korean and Japanese workers. The distributions of scores o n the questionnaire for these two groups were normal and its mean slig htly moved to the Morning type with aging. It is noteworthy, however, that the mean scores of Korean workers was lower than those of the Jap anese workers. The self-reported waking times and bedtimes for the two groups gradually became earlier with aging. From these results it cou ld be said that aging was an factor that led to the difference of circ adian phase.