The role of chronotype,gender, test anxiety,and conscientiousness in academic achievement of high school students

Previous findings have demonstrated that chronotype (morningness/intermediate/eveningness) is correlated with cognitive functions, that is, people show higher mental performance when they do a test at their preferred time of day. Empirical studies found a relationship between morningness and higher learning achievement at school and university. However, only a few of them controlled for other moderating and mediating variables. In this study, we included chronotype, gender, conscientiousness and test anxiety in a structural equation model (SEM) with grade point average (GPA) as academic achievement outcome. Participants were 158 high school students and results revealed that boys and girls differed in GPA and test anxiety significantly, with girls reporting better grades and higher test anxiety. Moreover, there was a positive correlation between conscientiousness and GPA (r = 0.17) and morningness (r = 0.29), respectively, and a negative correlation between conscientiousness and test anxiety (r = –0.22). The SEM demonstrated that gender was the strongest predictor of academic achievement. Lower test anxiety predicted higher GPA in girls but not in boys. Additionally, chronotype as moderator revealed a significant association between gender and GPA for evening types and intermediate types, while intermediate types showed a significant relationship between test anxiety and GPA. Our results suggest that gender is an essential predictor of academic achievement even stronger than low or absent test anxiety. Future studies are needed to explore how gender and chronotype act together in a longitudinal panel design and how chronotype is mediated by conscientiousness in the prediction of academic achievement.     

Individual differences in chronotypes associated with academic performance among Chilean University students

A chronotype is an individual trait that determines circadian rhythm (dark/light cycle) characteristics, associated with bedtime, waking, and other daily activities. A chronotype is classified as morning, intermediate, and evening. The objective is to associate chronotypes with academic performance in university students. A cross-sectional study was performed to evaluate the chronotype of university students (n = 703) by Horne-Ostberg questionnaire and associated with academic performance. The group with higher GPAs had higher chronotype scores (p = 0.002). Morning and intermediate chronotypes exhibited better academic performance; however, more studies are necessary to determine the underlying causes, which could influence cognitive aspects.     

The influence of chronotype on the academic achievement of children and adolescents – evidence from Russian Karelia

The inter-individual differences of human time-of-day preferences could divide population into “morning”, “intermediate” and “evening” types. This variety of sleep patterns is accompanied by differences in the timing of peak cognitive performance. The morningness–eveningness trait, also known as chronotype, is distributed on a continuum, with unequivocal early morning and night owl types at the opposite extremes of the distribution while most of the population shows an intermediate or neither type weak sleep pattern. Obviously, the discrepancy between biological and the social clocks has a distinct impact on physiological processes in humans with different chronotype. It is known that natural light regime in circumpolar regions influences human performance. Most work focused on the relationship between academic achievement and chronotype in students from middle latitudes. The primary aim of our study is to investigate the relationship between chronotype and academic achievement in schoolchildren (6th–11th grade) from north-west Russia (Russian Karelia). The Munich chronotype questionnaire was used in the study, and all participants were required to answer a question about their school achievement. Early midpoint of sleep and longer average sleep duration were associated with better grades. Large social jetlag was associated with worse grades. In a linear regression, gender was the most important predictor of grades, followed by midpoint of sleep and age. This is the first study that has been carried out among school pupils from Russian Karelia, and it shows that evening orientation linked with poorer academic grades at this high latitude.     

Chronotype,class times,and academic achievement of university students

Numerous studies over the years have documented an effect of human chronotypes on physiological and psychological processes. Studies evaluating the impact of an individual’s chronotype on his/her academic achievement have indicated that morning chronotypes have an academic advantage over evening chronotypes. However, these studies did not account for the time of day in which the participants were being evaluated. The goal of the present study was to examine whether morning chronotypes do have an academic advantage over evening chronotypes when the time of day of classes and exams is taken into consideration. We obtained morningness–eveningness scores and course grades from 207 university students who took classes (and exams) at different times of the day. We confirmed that morning chronotypes attain better grades than evening chronotypes, although the association is weak (r² = 0.02). The difference persisted even after the time of day of classes and exams was taken into consideration. This is probably due to the fact that evening chronotypes are generally more sleep deprived than morning chronotypes as a result of the early schedule of most schools, which can impair their performance both early and late in the day.     

Circadian Preference and Thinking Styles: Implications for School Achievement

Research has shown that thinking styles could have an influence on academic achievement. Previous studies have described that evening types are usually right-thinkers who tend to be creative and intuitive, whereas morning types tend to be left-thinkers who prefer verbal and analytic strategies in processing information. However, these studies have been realized among undergraduates, who have more freedom to choose their time schedules according to their circadian preference than adolescents or adult workers. On other hand, the relationship between thinking styles and circadian preference has not been analyzed considering school achievement. The present study aims (1) to investigate the relationship between circadian preference, that is, behavioral differences in circadian rhythmic expression, and thinking styles, referring to the preference toward information processing typical of the right versus the left cerebral hemisphere; and (2) to test the implications for self-reported school achievement. A sample of 1134 preadolescents and adolescents (581 girls; mean?±?SD age: 12.1?±?1.47, range: 10–14?yrs) completed the Morningness-Eveningness Scale for Children (MESC) as measure of circadian preference (morning, neither, or evening types), the Hemispheric Preference Test (HPT), conceived as a tool to measure thinking styles (right-, balanced-, and left-thinkers), and self-reported school achievement. Results indicated a greater percentage of left-thinkers among morning types and a greater percentage of right-thinkers among evening types. No differences were found among balanced-thinkers and neither types. Morning types and left-thinkers reported the highest subjective level of achievement, followed by evening types and left-thinkers, and morning types and right-thinkers. Evening types and right-thinkers reported the lowest subjective level of achievement. Finally, multivariate regression analysis indicated that age, left hemisphere and morning preferences accounted for 14.2% of total variance on self-reported achievement.     

Impairment of sleep quality and quality of life in bimodal chronotype individuals

There is still insufficient data about the characteristics and clinical significance of the bimodal chronotype. We evaluated more than 1000 students with Morningness-Eveningness Questionnaire, Munich Chronotype Questionnaire (MCTQ), Pittsburgh Sleep Quality Index and 36-item Short Form Health Survey. Twelve percent of the sample was bimodal and they showed similar results to intermediate chronotype in MCTQ-chronotype and social jetlag, both different from morning and evening chronotypes. However, their quality of life and sleep quality were similar to evening types, both different from morning and intermediate types. We discuss if being bimodal would be a maladaptive aspect of circadian preference     

Chronotype and time metaphors: morning-types conceive time as more friendly and less hostile

Recent studies have shown that diurnal preference (Morningness–Eveningness, also labeled chronotype) is an important predictor of temporal perspectives. In the present paper we draw upon these results in a study aiming to investigate differences between Morning-, Neither- and Evening-types in conceiving time. Based on data gathered from a sample of 316 university students, we analyzed associations between chronotype and dimensions of Time Metaphors Questionnaire. Morning preference was associated with a more positive, friendly view of time, whereas evening preference was related to conceiving time as negative and hostile. The above results were obtained using both dimensional and circadian typology approaches. The results are in line with a growing body of data indicating elevated negative emotionality of Evening-types. Possible mechanisms underpinning these associations are discussed in light of recent developments in the field of chronopsychology.     

Chronotype and postmenopausal breast cancer risk among women in the California Teachers Study

ABSTRACT

Chronotype is the behavioral manifestation of an individual’s underlying circadian rhythm, generally characterized by one’s propensity to sleep at a particular time during the 24 hour cycle. Evening chronotypes (“night owls”) generally suffer from worse physical and mental health compared to morning chronotypes (“morning larks”) – for reasons that have yet to be explained. One hypothesis is that evening chronotypes may be more susceptible to circadian disruption, a condition where the coordinated timing of biologic processes breaks down. The role of chronotype as an independent or modifying risk factor for cancer has not been widely explored. The objective of the current study was to evaluate the risk of breast cancer associated with chronotype in a case-control study nested within the California Teachers Study (CTS) cohort. The study population consisted of 39686 post-menopausal CTS participants who provided information on chronotype by completing a questionnaire in 2012–2013. 2719 cases of primary invasive breast cancer diagnosed from 1995/1996 through completion of the chronotype questionnaire were identified by linkage of the CTS to the California Cancer Registry. 36967 CTS participants who had remained cancer-free during this same time period served as controls. Chronotype was ascertained by responses to an abbreviated version of the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ) and was characterized into five categories: definite morning, more morning than evening, neither morning or evening, more evening than morning, definite evening. Multivariable unconditional logistic regression analyses were performed to estimate the odds ratios (ORs) and 95% confidence intervals (95% CIs) for each of the chronotypes, adjusted for established breast cancer risk factors. Compared to definite morning types, definite evening types had an increased risk of breast cancer with elevated ORs that were statistically significant in both the crude (OR = 1.24, 95% CI: 1.10–1.40) and fully-adjusted models (OR = 1.20, 95% CI: 1.06–1.35). The risk estimates in the fully-adjusted model for all other chronotypes did not significantly differ from one. These results suggest that evening chronotype may be an independent risk factor for breast cancer among a population of women who are not known to have engaged in any substantial night shift work. Further research in other populations of non-shift workers is warranted.     

The association between sleep chronotype and obesity among black and white participants of the Bogalusa Heart Study

ABSTRACT

Research indicates that sleep duration and quality are inter-related factors that contribute to obesity, but few studies have focused on sleep chronotype, representing an individual’s circadian proclivity, nor assessed these factors in racially diverse middle-aged samples. We examined the associations between chronotype and obesity among black and white men and women participating in the Bogalusa Heart Study (BHS).

Body mass index (BMI) and sleep data were available for 1,197 middle-aged men and women (mean age 48.2 ± 5.3 years) who participated in the BHS 2013–2016. Based on the reduced Morningness-Eveningness Questionnaire’s cutoff values for chronotypes, we combined ‘definitely morning’ and ‘moderately morning’ types into ‘morning’ type, ‘definitely evening’ and ‘moderately evening’ types into ‘evening’ type and kept those who were “neither” type in a separate group. We used ‘morning’ type as the referent group. Obesity was defined as a BMI ≥ 30. Multivariable logistic regression models were used to examine associations adjusting for sex, age, education, smoking, alcohol use and drug use, depression, shift work, physical activity and sleep duration.

Evening chronotype, reported by 11.1% of participants, was associated with obesity after multi-variable adjustment, including shift work, physical activity and sleep duration (OR 1.67, 95% CI: 1.08–2.56). However, once stratified by race (black/white), this association was found only among white participants (OR = 1.91, 95% CI = 1.12–3.25) after full adjustment.

In our biracial, community-based population, evening chronotype was independently associated with obesity, specifically among white participants. Further research is needed to identify behavioral, endocrine, nutritional and genetic pathways which underlie these associations.     

Associations between chronotypes and psychological vulnerability factors of depression

Chronotypes have been associated with psychopathology. The eveningness chronotype has been consistently linked with depressed states or depressive disorder, but the underlying mechanism remains unclear. Prior studies have shown associations between chronotype and personality traits that are linked to depression (e.g. neuroticism), but other psychological vulnerability factors have not been previously investigated in relation to chronotypes. The aim of this study was to examine the association between chronotypes, depression and psychological risk factors of depression (namely, cognitive reactivity and worry), in a large cohort of depressed patients and healthy individuals. We used data from the Netherlands Study of Depression and Anxiety (n = 1654), which includes 1227 clinically diagnosed individuals with a lifetime diagnosis of depression and 427 healthy controls. We assessed cognitive reactivity (Leiden Index of Depression Sensitivity-Revised) and trait worry (Penn State Worry Questionnaire). We controlled for sociodemographic factors as well as for insomnia and neuroticism. We found that the evening type is associated with higher cognitive reactivity scores, especially with increased rumination. Cognitive reactivity also mediated the relationship between chronotype and depression status, even when controlling for neuroticism and insomnia. Trait worry was not associated with chronotype. Our findings show that depressogenic cognitions are more prevalent in evening types and perhaps mediate the association between chronotype and depression. Further prospective research is needed to determine the timeline of the association. Nevertheless, results imply that targeting depressogenic cognitive processes, perhaps in combination with chronotherapeutic treatments, may be particularly useful in evening types.     

The Relationship between Sleep and Shift System, Age and Chronotype in Shift Workers

The purpose of this study was to investigate the effects of shift system, age, and chronotype on the sleep habits, sleepiness and catnaps of shift workers during night work. We administrated a Morningness-Eveningness Questionnaire and Life Habits Inventory to 561 male shift workers of three different shift systems in Korea. The mean scores on the Morningness-Eveningness Questionnaire clearly shifted toward the Morning type from the young to old groups. The waking and bedtimes during the day and evening shift were earlier for the older than for the younger groups, and these times were earlier across the Evening, Intermediate, to Morning type as well. Sleep length during the day shift was longer from the young to old, and it was shorter from the Evening, Intermediate, to Morning type. In the weekly rotation full-day 3-team 3-shift system and continuous full-day 3-team 3-shift system (which had earlier starting times for day shift) the sleep length of the younger workers was short. For the aged workers, sleep length during the night shift was short because they woke up early. In the weekly rotation full-day 2-team 2-shift system that had a short working interval, the reduction of sleep length during night shift was greater than that of the other shift systems. However, the scores on the Morningness-Eveningness Questionnaire showed a significantly negative correlation only in the bedtime during day shift among the sleep habit parameters for the independent variable by age. For the percentage of subjects that reported 'become sleepiness', the degree and time of sleepiness during the night shift were greater and earlier for the older than for the younger workers, and greater for the Morning than for the Evening type. The percentage of subjects who took a catnap during night shift, as well as the length of their catnap, were also higher and longer for the older groups, and higher and longer for the Morning type than for the Evening type. From these results, we surmised that the sleep habit parameters were influenced the age or shift systems rather than the chronotype. The sleep length during the night shift was shorter for the aged than for the young. In the shift systems that have a short working interval, the nocturnal was remarkably shorter for the young than the aged. The aged had not adapted their sleep for the night shift compared to the young, this suggested by the aged's strong complaint of sleepiness and by the fact that a larger percentage of aged subjects said they took catnaps during night shift compared to the younger workers.     

Chronotype and the Transition to College Life

Social synchronizers of morningness-eveningness, or chronotype, begin to change during the developmental transition from adolescence to college life. The current study examined how these changes related to the sleep/wake patterns of 220 undergraduates (93 males/122 females) ranging in age from 18 to 29 yrs at a private university. Coping strategies students used to deal with early morning commitments and familial conflict over sleep patterns were also examined. Results revealed that evening chronotypes were more likely to report conflict with parents in junior high school and high school over going to bed and waking, followed by a shift to a later sleep/wake pattern in college. They also reported adjusting their schedules and using more coping strategies to accommodate their evening bias. Morning chronotypes, whose routines easily fit a conventional morning schedule, reported little change in schedules and sleep patterns from junior high school to college, and used fewer coping strategies in response to early morning commitments. The shift in social zeitgebers from junior high school to college are significant, and yet little research has examined the effect these changes can have on students' adjustment to college life and the role that chronotype plays in this process. Because students' ability to cope with these changes will ultimately influence how successful they are in their various endeavors, a greater understanding of how chronotype is related to adaptive functioning across this developmental period is needed. (Author correspondence: lzimmerm@su.edu)     

The Circadian Energy Scale (CIRENS): Two Simple Questions for a Reliable Chronotype Measurement Based on Energy

This study presents the Circadian Energy Scale (CIRENS), a very short and simple chronotype measurement tool based on energy. The CIRENS consists of two introspective questions about the usual energy level (very low, low, moderate, high, or very high, scored 1 to 5) in the morning and in the evening. The difference between energy level scores (?4 to 4) felt by respondents in the evening and morning defines the chronotype score and classification. A concurrent validity analysis of the CIRENS with the widely used Horne and Östberg Morningness-Eveningness Questionnaire (MEQ) was conducted using a sample of 225 college students, and with MSFsc, a sleep-based chronotype assessment tool based on the Munich Chronotype Questionnaire (MCTQ), using a sample of 34,530 subjects (18–83 yrs, 27% males). This large sample was collected in a Web survey for behavioral correlates of the CIRENS with variables previously associated with chronotype differences. The correlation of the CIRENS chronotype score was r?=??.70 with the MEQ and r?=?.32 with the MSFsc. CIRENS chronotype scores declined with age and were not affected by sex. Both CIRENS and MSFsc chronotype scores were related to differences in tobacco, caffeine, and cola soft-drink consumption (all higher in evening types). The CIRENS provides a simple chronotype index and a measure of absolute energy throughout the day and seems to be a reliable chronotype assessment tool that may be useful both clinically and for large-scale studies. (Author correspondence: diogorlara@gmail.com)     

The Relationship between Sleep and Shift System,Age and Chronotype in Shift Workers

The purpose of this study was to investigate the effects of shift system, age, and chronotype on the sleep habits, sleepiness and catnaps of shift workers during night work. We administrated a Morningness-Eveningness Questionnaire and Life Habits Inventory to 561 male shift workers of three different shift systems in Korea. The mean scores on the Morningness-Eveningness Questionnaire clearly shifted toward the Morning type from the young to old groups. The waking and bedtimes during the day and evening shift were earlier for the older than for the younger groups, and these times were earlier across the Evening, Intermediate, to Morning type as well. Sleep length during the day shift was longer from the young to old, and it was shorter from the Evening, Intermediate, to Morning type. In the weekly rotation full-day 3-team 3-shift system and continuous full-day 3-team 3-shift system (which had earlier starting times for day shift) the sleep length of the younger workers was short. For the aged workers, sleep length during the night shift was short because they woke up early. In the weekly rotation full-day 2-team 2-shift system that had a short working interval, the reduction of sleep length during night shift was greater than that of the other shift systems. However, the scores on the Morningness-Eveningness Questionnaire showed a significantly negative correlation only in the bedtime during day shift among the sleep habit parameters for the independent variable by age. For the percentage of subjects that reported 'become sleepiness', the degree and time of sleepiness during the night shift were greater and earlier for the older than for the younger workers, and greater for the Morning than for the Evening type. The percentage of subjects who took a catnap during night shift, as well as the length of their catnap, were also higher and longer for the older groups, and higher and longer for the Morning type than for the Evening type. From these results, we surmised that the sleep habit parameters were influenced the age or shift systems rather than the chronotype. The sleep length during the night shift was shorter for the aged than for the young. In the shift systems that have a short working interval, the nocturnal was remarkably shorter for the young than the aged. The aged had not adapted their sleep for the night shift compared to the young, this suggested by the aged's strong complaint of sleepiness and by the fact that a larger percentage of aged subjects said they took catnaps during night shift compared to the younger workers.     

Chronotype and the transition to college life

Social synchronizers of morningness-eveningness, or chronotype, begin to change during the developmental transition from adolescence to college life. The current study examined how these changes related to the sleep/wake patterns of 220 undergraduates (93 males/122 females) ranging in age from 18 to 29 yrs at a private university. Coping strategies students used to deal with early morning commitments and familial conflict over sleep patterns were also examined. Results revealed that evening chronotypes were more likely to report conflict with parents in junior high school and high school over going to bed and waking, followed by a shift to a later sleep/wake pattern in college. They also reported adjusting their schedules and using more coping strategies to accommodate their evening bias. Morning chronotypes, whose routines easily fit a conventional morning schedule, reported little change in schedules and sleep patterns from junior high school to college, and used fewer coping strategies in response to early morning commitments. The shift in social zeitgebers from junior high school to college are significant, and yet little research has examined the effect these changes can have on students' adjustment to college life and the role that chronotype plays in this process. Because students' ability to cope with these changes will ultimately influence how successful they are in their various endeavors, a greater understanding of how chronotype is related to adaptive functioning across this developmental period is needed.     

The Circadian Energy Scale (CIRENS): two simple questions for a reliable chronotype measurement based on energy

This study presents the Circadian Energy Scale (CIRENS), a very short and simple chronotype measurement tool based on energy. The CIRENS consists of two introspective questions about the usual energy level (very low, low, moderate, high, or very high, scored 1 to 5) in the morning and in the evening. The difference between energy level scores (-4 to 4) felt by respondents in the evening and morning defines the chronotype score and classification. A concurrent validity analysis of the CIRENS with the widely used Horne and ?stberg Morningness-Eveningness Questionnaire (MEQ) was conducted using a sample of 225 college students, and with MSFsc, a sleep-based chronotype assessment tool based on the Munich Chronotype Questionnaire (MCTQ), using a sample of 34,530 subjects (18-83 yrs, 27% males). This large sample was collected in a Web survey for behavioral correlates of the CIRENS with variables previously associated with chronotype differences. The correlation of the CIRENS chronotype score was r?=?-.70 with the MEQ and r?=?.32 with the MSFsc. CIRENS chronotype scores declined with age and were not affected by sex. Both CIRENS and MSFsc chronotype scores were related to differences in tobacco, caffeine, and cola soft-drink consumption (all higher in evening types). The CIRENS provides a simple chronotype index and a measure of absolute energy throughout the day and seems to be a reliable chronotype assessment tool that may be useful both clinically and for large-scale studies.     

The synchrony effect revisited: chronotype,time of day and cognitive performance in a semantic analogy task

ABSTRACT

The synchrony effect (i.e. superior performance at optimal, inferior performance at suboptimal times of day) has been broadly studied within the context of circadian rhythms. Whether one chronotype copes better with the synchrony effect than the other received only insufficient empirical attention. We report on an applied experimental study investigating the impact of chronotype on the synchrony effect in a semantic analogy task. To detect an analogy, 36 participants (12 males) aged between 18 and 40 had to decide whether the relation between events of a source pair was mirrored by the relation between events of a target pair (e.g. to cook: to eat = to saddle: to ride). Temporal orientation of the relation within each event pair was varied corresponding either to the chronological or reverse order. Response times (RTs), error rates, as well as the psychophysiological parameters pre-experimental pupil baseline and peak pupil dilation replicate findings of a synchrony effect (shorter RTs and allocation of less cognitive resources at optimal times of day) and show an impact of chronotype (morning types generally outperforming evening types). Most importantly, morning types appeared to cope better with the synchrony effect than evening types: At suboptimal times, morning types solved the analogy detection task more efficient; that is faster with the same accuracy and without the investment of more cognitive resources. They also showed greater alertness and wakefulness indexed by greater pre-experimental pupil baselines. At optimal times of day, morning types have more cognitive resources available to allocate these to the more demanding conditions to outperform evening types. We interpret these findings to suggest that morning types are more able to adapt to unfavourable circumstances (for instance, by avoiding wasteful resource allocation when there are less cognitive resources available). Evening types appear less able to adapt to suboptimal times than morning types, because they have to deal with social jetlag and decreased self-control.     

Evening types are prone to depression

Certain preferences for the timing of daily activities (chronotype) may predispose an individual to sleep problems and mood disorders. In this study, we have examined the link between chronotypes and depression. Participants (N?=?6071) were recruited from a random sample of the general population aged 25 to 74 yrs living in defined geographical areas, as part of the National FINRISK Study in 2007 in Finland. Chronotype assessment was based on six items from the original Horne-Östberg Morningness-Eveningness Questionnaire. Depression was assessed with four self-reported items, including two probes for a diagnosis of a major depressive episode, diagnosed or treated depression, and use of antidepressants. We also analyzed correlations between chronotype and several health indicators, such as systolic and diastolic blood pressures, resting heart rate, weight, and waist circumference. The odds ratios for a range of indicators of depression were higher for evening types (2.7- to 4.1-fold) and intermediate types (1.5- to 1.9-fold) than for morning types. Our results suggest that individuals having a preference for evening hours to carry out their daily activities are prone to depression. (Author correspondence: ilona.merikanto@helsinki.fi)     

Additional psychometric evidence and construct validity for a revised Preferences Scale of morningness

The Preferences Scale of morningness was originally conceived as a two-factor, 11-item model. More recently, a two-factor, six-item model has been developed and supported in two independent samples. These competing models were examined using structural equation modeling in a mixed student and working sample (n=120). The results supported the two factor, six-item model (chi(2)(8, N=120)=10.84, p>0.05) as best fitting the sample data. The two factors explained 59% of the variance and Cronbach's alpha was 0.71. Significant differences (p<0.01) in self-reported driving ability between morning and evening types were obtained by time-of-day, providing some evidence of construct validity. Morning types rated their performance as better in the morning hours and evening types rated their performance as better at night. We then examined whether self-rated performance is subject to some degree of bias. For both morning and evening types, there was a tendency for those scoring high on self-deception to rate their driving ability as better, but these differences were not significant. Overall, these findings suggest that self-ratings are suitable for use in determining construct validity. Recommendations for future studies are made.