Background: Sleep quality has a significant impact on the psychological aspects of people and can be change by biological aspects. The aim of the present study was to investigate the components of sleep quality based on the morning and evening and the role of reinforcement sensitivity theory and gender.
Materials and methods: The research design was ex-post facto. For this purpose, initially 490 students of Bu-Ali-Sina University were selected and morning/evening questionnaires were distributed among them. Then, 135 participants were selected for the second stage according to the obtained scores in the morning and evening questionnaires, in the form Morningness and eveningness and intermediate individuals. Finally, Sleep quality scale and sensitivity to reward and punishment scale in order to collect data were distributed among study participants.
Results: Our findings indicated significant differences among components of sleep quality based on the types of Morningness and eveningness and intermediate (p<0.05). So that eveningness types had a higher scores in delay falling asleep and sleep duration. Also, women in the dimensions of delay falling asleep disorders and sleep-inducing drugs showed higher scores than males (p<0.05).
Conclusion: It seems that individual differences in circadian cycles, plays an important role in sleep quality.