Background: Survey on different biological dimensions of personality consisting of morningness and eveningness types and their influence on different aspects of psychological damages of adolescents seem to be a necessary scope of study. The aim of the present study was to investigate psychological damage levels in adolescents based on their biological personality types Including morningness and eveningness.
Materials and methods: For this purpose, 362 High school students in Bushehr city were selected using multistage cluster sampling. Then, morningness-eveningness questionnaire was distributed among them. After analysing the initial results, 61 participants were selected for the second stage based on their scores in personality traits questionnaire, as individuals with morning, evening and intermediate type categories. Finally, in order to test the hypothesis of this study, psychological symptoms assessment questionnaire (SCL-90-R) was distributed among them. The collected data were analysed to investigate the research goals.
Results: it was indicated significant differences between dimensions of psychological damage based on the morning, evening, and intermediate types of personality: evening types had higher scores in all components of the measurement of psychological damage.
Conclusion: It seems that individual differences in biological cycles of adolescents’ personality may be related with the levels of psychological damage.