The purpose of this study was to assess the domains of cognitive abilities and affective styles of adjusting, concealing, and tolerating based on individual differences in morningness and eveningness personality tendencies.
For this purpose, initially 304 students of Urmia University were selected through multistage cluster sampling. Then morningness and eveningness types questionnaire was distributed among them to be answered. After analyzing the initial results, 60 participants were selected as individuals with morningness and eveningness and intermediate according to obtained scores in morningness and eveningness questionnaire. Finally, cognitive abilities and affective styles questionnaires were distributed individually among the participants in order to gather the data. The data were analyzed by using descriptive indicators, multivariate analysis of variance (MANOVA), one-way ANOVA and tukey post hoc test.
Findings: Results indicated significant differences between dimensions of cognitive abilities based on tendencies of morningness and eveningness and intermediate and eveningness types in comparison with morning persons had higher abilities in some dimensions including inhibitory control, decision-making and attention. (P

The aim of the current research was to study the role of behavioral activation/ Inhibition system and morningness and eveningness type with student's positive emotion achievement. Its descriptive and correlational design and statistical population included all first-grade high school male students in Chaypareh City in 2019-2020. In the same light, 211 subjects were selected using the multi-stage cluster sampling method. The Pekrun's achievement emotions, the Carver and White's Behavioral activation/ Inhibition, and the Horne and Östberg's morningness and eveningness type inventories were used to gather the data. Multivariate regression revealed that behavioral activation/ inhibition system and morningness and eveningness type significantly predict positive achievement emotions. Biological factors seem to play a role in morningness and eveningness type and the regulation of behavioral inhibition and activation systems as well, the morningness types and behavioral activation systems play a role in positive achievement emotions.

The aim of the present study was to investigate psychological well-being and Sensory processing sensitivity levels based on the change in the circadian cycle Morningness and eveningness. For this purpose, Initially 475 students of Urmia were selected, in the form multistage cluster sampling, Then Morningness and eveningness types Questionnaire In order to responding were distributed among them. After analysing the initial results, 51 participants were selected for the second stage According to obtained scores in personality traits questionnaire Morningness and eveningness, as individuals with Morningness and eveningness and intermediate. Finally, , in order to test the hypothesis of this study, participants were have studied to measure well-being and processing sensitivity, Psychological well-being scale and scale of individual with sensory processing sensitivity were distributed among participants in the study in order to collect data. Collected data were analyzed to investigate the research goals. Results indicated significant differences between dimensions of Psychological well-being based on the types of Morningness and eveningness and intermediate, Morningness types had a lower Psychological well-being, also comparison of Morningness and eveningness in Sensory processing sensitivity Dimensions, showed that groups of Morningness types had higher sensitivity to stimulus.Discussion and It seems that individual differences in circadian cycles, may be related to levels of mental health and lead to different reactivity to stimulants..

This study aimed to investigate the relationship between morningness, eating behaviors, positive and negative affect and eating chocolate and to evaluate these variables with regard to eating breakfast.
The study design was correlational. 125 undergraduate students of Faculty of Psychology and Education of University of Tehran completed Dutch Eating Behavior Questionnaire, Positive and Negative Affect Scale and Composite Scale of Morningness. 80 of these subjects then participated in a chocolate sham-palatability test. The number of chocolates participants tasted was considered as an objective measure of eating behavior.
Morningness had positive relationship with positive affect (r=0.35, p The correlation between the number of chocolates consumed and emotional eating is an important finding of the study introducing the test for objective measurement of emotional eating phenomenon. In addition, morningness was correlated with positive affect and external eating that is in accordance to previous research.

Biological aspects of personality have an important influence on people psychological dimensions. People affective and mood states can be changed based on cycle of Hostelry. The aim of the present study was to investigate negative/positive affect levels and reinforcement sensitivity based on the change in the circadian cycle morningness and eveningness. First, 600 students (316 girls, 284 boys) from the University of Urmia participated in the study. Participants completed the Morningness-Eveningness Questionnaire (MEQ). Then, 83 participants were selected for the second stage according to obtained scores in MEQ, as morningness, eveningness, and intermediate individuals. Finally, participants completed the Positive and Negative Affect Schedule (PANAS) and the Behavioral Activation System (BAS) and Behavioral Inhibition System (BIS) Scales. Results indicated significant differences among dimensions of positive and negative affect based on the types of morningness, eveningness, and intermediate types. The morningness type had a higher positive affect and lower negative affect. Comparison of morningness and eveningness types in the biological aspects of personality including behavioral activation and behavioral inhibition showed no significant difference between the two groups. Based on the study results, this can be concluded that individual differences in experience of positive and negative affect can be caused by changes associated with circadian cycles.

Learning and performance of different people is influenced by an intrinsic clock and they can be classified into three groups: morningness, eveningness and non morningness-non eveningness. Cognitive performance of people is congruent with such rules and it approach maximum at different times of day. In higher education curriculum planning it is accepted to arrange difficult courses be presented early morning to seek better learning. This study is aimed at investigating the relationship of medical students’ academic merits with their morningness-eveningness schedule with regard to difficult and easy courses. this research is a retrograde descriptive –analytic study. Fifth semester medical students involved in this study. Their morningness-eveningness schedule was defined by the use of a 19 items questionnaire and they were asked to determine difficulty of different courses. The critical threshold for difficulty of each course was considered by 50%. Students’ manuscripts extracted from medical school educational officials. SPSS software (ver 11.5) was used for data analysis through “t”, ANOVA and multiple regression. 63(67% female and 33% male) students participate in the study. Physiology, pathology and parasitology were considered as difficult courses and Islamic ethics, nutrition, analytical history of islam, practical parasitology and physiology considered as easy courses. 11%, 60% and 29% of students were considered morningness, nonmorningness-noneveningness and eveningness, respectively. As a result, eveningness females have a considerable decrease in difficult courses (Pvalue of physiology=0.009, pathology=0.005 and parasitology=0.059). Such decrease in males was not significant. Although, it is believed that difficult courses should be presented in early morning for better learning this study shows that eveningness students’ performance may decline significantly and it is recommended to arrange for difficult courses to be presented in special times for better performance of all students categories.

Simultaneous occurrence of psychiatric disorders and substance abuse disorders have widespread effects and are associated with worse prognosis. Addicts should be treated in accordance with the requirements of each of these people. This study aimed at investigating the simple and multiple relationships between morningness/eveningness, anxiety sensitivity and addiction potential in university students. For this purpose 380 students were selected by cluster sampling from Islamic Azad University and payamenoorfarshband. The scales used for this descriptive study were anxiety sensitivity index (ASI), Composite Scale Of morningness (CSM) and Iranian Addiction Potential Scale (IAPS). For data analysis, simple correlation and regression methods were used. There were simple and multiple relationships between morningness/eveningness, anxiety sensitivity and addiction potential. Multiple regression analysis showed that morningness/eveningness, anxiety sensitivity had significant multiple correlation with addiction potential. But Anxiety sensitivity towards morningness further predicted addiction potential. According to research results can be said to individuals that have anxiety and fear and unable to control their anxiety, May have to use drugs to control their own. Inaddition Individuals who have morning personalities are less inclined to use drugs because they are more refreshed in the morning.

Circadian rhythm and motor imagery according to the rhythm are one of the factors that appears in learning motor skills. The aim of present study is determining the timing of the circadian rhythm in physical training and motor imagery on learning tennis on table forehand in individuals with different circadian. This study was of type semi-experimental and done by pretest and posttest. For this purpose, selected 40 novice participants, right –handed, their average age was 22±3/21. Individuals selected in order to standard scales this study and circadian types. They randomly assigned for four groups. The first group (morningness) performed just physical training and group second (morningness) had combination practice (motor imagery and physical training). Both of them practiced in the morning. The third group (eveningness) performed just physical training and the fourth group had combination practice (motor imagery + physical training). Both of them practiced in the afternoon. The groups had five sessions for training on skill after pretest. The final they evaluated with retention test in the morning and afternoon. The data in acquisition phase analyzed of variance with repeated measures 4 (experimental group) × 5 (number of training sessions) and the retention of tow-way variance 2 (circadian rhythm: practice in the morning and afternoon) ×2 (type of exercise: combination and just physical training). The results showed that individual ‘s performance was better during the acquisition phase than the other session in the fourth and fifth sessions. Examination of averages showed the weakest performance in physical training group (morningness) and the best performance in combination group (eveningness) (p<0.001). Morningness individual better than the eveningness individual in the first retention test (retention test in the morning) (P<0.001). Results in the second retention test (retention in the afternoon) showed better performance for eveningness individual, also combination group (eveningness) had better performance in the second retention and combination group (morningness) had weakest performance (P<0.001). The results showed the motor imagery and physical training on learning motor skill is influenced by individual’s circadian rhythm and their practice timing in the morning or afternoon, so we can use of suitable timing according circadian rhythm as important factor in improving the performance of motor skills.

Academic achievement, which happens when there is no distance between learning capacity and academic performance, is affected not only by differences in IQ, but also by personality variables. The aim of this study was to investigate the role of brain/behavioral systems and morningness-eveningness types in predicting academic achievement in elementary school students in Baneh County, Kurdistan. The method used in this study was correlational, and the statistical population consisted of 160 primary school students, in fourth, fifth and sixth grades, in the academic year 2015-2016 (1394-1395), which were selected by cluster sampling. To collect data, Behavioral Inhibition/Activation systems scale (BIS/BAS) questionnaire of Carver and White, and the Horne & Östberg's Morningness-Eveningness questionnaire were used, and the collected data were analyzed by the Pearson correlation coefficient and Multiple Regression Analysis. The results showed that academic achievement has a positive correlation with sensitivity to reward (r= 0.34: p<0/002), drive (r=0.45, p<0/001) and behavioral activation system and morningness (r= 0/34: p<0/002), but it has a negative correlation with fun seeking (r=-0/22: p<0/043) and sensitivity to punishment (r=-0/39:p<0/001).The results also showed that drive and the extent of morningness-eveningness components could predict 22/2% and 11/6% of changes in students’ academic achievement, respectively. The results also showed that the more sensitive students are to reward and drive, and are more of morningness types, they show more academic achievement.

Objectives This research was conducted with the goal of comparison of executive functions, risk behaviors, and academic motivation among adolescents with chronology type morningness and eveningness.
Methods This is a comparative study in a population of high school students in Isfahan in 2014-15 academic year. Accessible sampling was used as a sampling method in two phases. In the first phase 320 students were selected, and in the second phase, 106 students with different chronology types were chosen as a final sample. The data gathered by using Horne and Östberg’s Morningness-eveningness questionnaire, Mohammadi and his colleagues’ Iranian Adolescents Risk Scale, Abdekhodaee’s Achievement motivation questionnaire, and Wisconsin card sorting test. Independent samples t test and Mann-Whitney U test were employed for analyzing data using SPSS-21.
Results Significant relationship was found between two aspects of executive functions containing preservation error and incorrect answers responses, and chronology types (PConclusion The adolescents with morningness chronology type performed better in executive function and academic motivation in comparison with eveningness type and had lower risky behaviors.