PARENTAL ENFORCEMENT OF BEDTIME DURING CHILDHOOD MODULATES PREFERENCE OF JAPANESE JUNIOR HIGH SCHOOL STUDENTS FOR EVENINGNESS CHRONOTYPE

We examined the effect of home bedtime discipline during childhood on morningness and eveningness (M-E) preference by Japanese junior high school students. M-E was assessed by the M-E Questionnaire (MEQ) of Torsvall and Åkerstedt (the higher the score, the greater the preference for morningness), and parental determination of bedtime during childhood was ascertained using an original questionnaire. The average M-E score of adolescents living in urban Kochi City (mean ± SD; 15.10 ± 3.42) was significantly lower (P <. 01) than the score of those in suburban districts (16.14 ± 3.44). Overall, 43.1% of the junior high school students in Kochi City compared to 53.0% of the students living in suburban districts had their bedtime decided during childhood by parents (P <. 01). In Kochi City, the M-E score for boys (14.62 ± 3.51) was lower (P <. 01) than girls (15.53 ± 3.28). During childhood, parents decided the bedtime for 49% of the girls compared to 36.6% of the boys (P <. 01). Boys whose bedtime was not decided by parents during childhood had a somewhat stronger preference for eveningness (14.20 ± 3.53) (P <. 05) compared to those whose bedtime was decided by parents (15.12 ± 3.36). The results suggest bedtime discipline at home during childhood has an effect on adolescent chronotype, modulating the extent of shift to eveningness in Japanese junior high school boys in particular. (Chronobiology International, 18(5), 823–829, 2001)     

Association between moringness-eveningness preference and mental/physical premenstrual symptoms in Japanese females 12 to 31 years of age

This study investigates the relationship between circadian typology, i.e., morningness-eveningness (M-E) preference, and the occurrence and severity of premenstrual mental and physical symptoms among 154 young Japanese female university students (range, 18 to 31 yrs; mean±S.D., 20.69±3.69 yrs) and 417 junior high school students (range, 12 to 15 yrs; mean±S.D., 14.29±0.67 yrs) living in an urban or suburban area of Kochi prefecture. Female university students experienced melancholy mood more frequently than did males, and the female university students who frequently became melancholy were more evening-typed than those who did not experience melancholy. Female university students who experienced frequent fluctuations in mood and/or menstrual pain were more evening-typed than those who were not so affected. M-E preference of junior high school students was not correlated with stability of mood or frequency of menstrual pain. In urban areas, however junior high school students who had very stable menstrual cycles were significantly more morning-typed than those whose menstrual cycles were not stable. In suburban areas, the bedtimes of female junior high students who had stable menstrual cycles were significantly earlier than those whose menstrual cycle duration was not stable. A physiological relationship between the circadian system, M-E, and attributes of the menstrual cycle seems to be present in adolescent female Japanese junior high school students.     

Association Between Moringness‐Eveningness Preference and Mental/Physical Premenstrual Symptoms in Japanese Females 12 to 31 Years of Age

This study investigates the relationship between circadian typology, i.e., morningness‐eveningness (M‐E) preference, and the occurrence and severity of premenstrual mental and physical symptoms among 154 young Japanese female university students (range, 18 to 31 yrs; mean±S.D., 20.69±3.69 yrs) and 417 junior high school students (range, 12 to 15 yrs; mean±S.D., 14.29±0.67 yrs) living in an urban or suburban area of Kochi prefecture. Female university students experienced melancholy mood more frequently than did males, and the female university students who frequently became melancholy were more evening‐typed than those who did not experience melancholy. Female university students who experienced frequent fluctuations in mood and/or menstrual pain were more evening‐typed than those who were not so affected. M‐E preference of junior high school students was not correlated with stability of mood or frequency of menstrual pain. In urban areas, however junior high school students who had very stable menstrual cycles were significantly more morning‐typed than those whose menstrual cycles were not stable. In suburban areas, the bedtimes of female junior high students who had stable menstrual cycles were significantly earlier than those whose menstrual cycle duration was not stable. A physiological relationship between the circadian system, M‐E, and attributes of the menstrual cycle seems to be present in adolescent female Japanese junior high school students.     

Correlation between breakfast tryptophan content and morning-evening in Japanese infants and students aged 0-15 yrs

Tryptophan can be metabolized via 5-hydroxytryptamine=serotonin to melatonin by a series of 4 enzymes in pineal body. Lack of serotonin in body fluid in the brain during daytime can lead to several psychiatric disorders, while shortage of plasma-melatonin at night can be related to sleep disorders. The Morning-Evening (M-E) questionnaire and the original questionnaire including questions on sleep habits, mental symptoms, and contents of meals were administered to 1055 infants aged 0-6 yrs, 751 students attending an elementary school, and 473 students attending junior high school in Kochi City (33 degrees N). The index of tryptophan taken at breakfast (Trp-Index) was calculated as tryptophan amount per one meal based on the tryptophan included in each 100 g of the foods and a standard amount of food per one meal. A significant positive-correlation between M-E scores and Trp-Index was not shown by relatively older students, aged 9-15 yrs (Pearson's test, r=0.044-0.123, p=0.071-0.505), whereas a significant positive correlation was shown by infants and young elementary school students aged 0-8 yrs (r=0.180, 0.258, p<0.001). The more frequently the infants had difficulty falling asleep at bedtime and waking up in the morning, the less the Trp-Indices taken at breakfast were (Kruskall-Wallis-test, p=0.027 for difficulty falling asleep; p=0.008 for difficulty waking up). The more frequently infants became angry even by a little trigger, or depressed, the lower (more evening-typed) the M-E scores were (Kruskal-Wallis test: p相似文献   

Advanced phases and reduced amplitudes are suggested to characterize the daily rest-activity cycles in depressed adolescent boys

Self-reported eveningness has been previously associated with depressed mood among adults and adolescents. Here, we study how circadian indicators based on actigraphic data differ between depressed and healthy adolescent boys. Our sample consisted of 17 medication-free adolescent boys, aged 14.5 to 17.5 years, of which eight had depressive disorder and were currently depressed and nine were healthy comparison participants. Psychiatric assessment was conducted by diagnostic interviews and complemented with observer-rating and self-rating scales. Actigraphic data were collected with wrist actigraphs for a minimum period of 25 consecutive days (range of 25 to 44 days). The behavioral trait of morningness–eveningness was measured with the 19-item Horne-Östberg Morningness–Eveningness Questionnaire. Based on the self-report, the depressed boys were more prone to eveningness than healthy controls, but based on the actigraphic data, they had earlier phases especially on school days and lower activity levels especially on weekends. On weekends, the depressed boys showed a greater shift toward later-timed phases than healthy controls. Our results confirm a mismatch of the subjective morningness–eveningness preference (late-preference) and the objective rest-activity rhythm (early-prone) during school days in depressed adolescent boys.     

Correlation between morningness-eveningness and final school leaving exams

Pupils shift their time of day preferences from morningness to eveningness during the age of puberty. Therefore, early school start times may have a negative influence on school functioning, adolescent health and on grade point average. Here, we show that morningness - eveningness influences school performance as measured by the final school leaving/university entrance certificate. One hundred and thirty-two university students aged between 20 and 22 years participated in our study. We found a highly significant positive correlation between the average grading of the final exam and the morningness score, suggesting that pupils with morning preferences performed better in school achievement. Evening types seem at a serious disadvantage because the final exams are used for university entrance decisions.     

Morning-evening preference: sleep pattern spectrum and lifestyle habits among Japanese junior high school pupils

We surveyed the sleep-wake patterns and lifestyle habits in a sample of Japanese first to third year junior high school children (n=638, age 12 to 15 yrs), of whom 29.3% were evening type, 64.1% intermediate type, and 6.6% morning type in preference. The morningness-eveningness (M-E) score was lower (more evening typed), 16.1 vs. 15.4 in first compared to third year students. There were significant gender differences, with girls showing a greater evening preference. Evening preference was associated with longer sleep latency, shortened sleep duration during schooldays and weekends, bad morning feeling, and episodes of daytime sleepiness. In contrast, morning preference was associated with higher sleep drive and better sleep-wake parameters and lifestyle habits. Our results suggest the morning preference should be promoted among junior high school children to increase the likelihood of more regular sleep-wake patterns and lifestyle habits.     

Is self-reported morbidity related to the circadian clock?

Morningness and eveningness preference, an endogenous component of the circadian clock, is characterized by an interindividual difference in circadian phase and requires of humans a specific timing of behavior. The biological rhythms of morning and evening types are consequently phase shifted with fixed socioeconomic constraints. The impact of this phase shift on health is widely debated. The purpose of the authors' study was to determine the influence of morningness/eveningness preference on self-reported morbidity and health in an active population. A total of 1165 nonshift workers of the French national electrical and gas company, enrolled in the GAZEL cohort and aged 51.3+/-3.3 years, were included in this study. They replied by mail with a completed questionnaire, including morningness/eveningness preference, self-reported morbidity, subjective sleep patterns, and daytime somnolence and sleeping schedules for 3 weeks, during the spring of 1997. Annual self-reported health impairments were assessed with the annual general questionnaire of the GAZEL cohort for 1997. After adjustment for age, sex, and occupational status, morningness-like and eveningness-like participants reported a specific worse self-reported morbidity. Whereas morningness was associated with worse sleep (p = 0.0001), eveningness was associated with feeling less energetic (p = 0.04) and physical mobility (p = 0.02). These relationships were observed even in good sleepers, except for physical mobility. After adjustment for confounding variables, eveningness-like participants reported more sleep (p = 0.0004) and mood (p = 0.00018) disorders than morningness-like participants. Morningness/eveningness preference was related to specific chronic complaints of insomnia: morningness was related with difficulty in maintaining sleep (p = 0.0005) and the impossibility to return to sleep in the early morning (p = 0.0001) (sleep phase-advance syndrome); eveningness was related to difficulty in initiating sleep (p = 0.0001) and morning sleepiness (p = 0.0001). In good sleepers, morningness was related with sleep phase-advance syndrome (p = 0.0001) and eveningness with morning sleepiness (p = 0.0001). In conclusion, the expression (phase advance or delay) of the circadian clock could be related to worse self-reported morbidity and health. These findings must be verified by further epidemiological studies, but they suggest that the impossibility to return to sleep in the early morning is not only associated with age.     

The influence of chronotype in the daily lives of young children

Research on chronotypic differences has been conducted for many years, however, until recently, little attention has been paid to young children. The current study examined the influence of morningness–eveningness in the daily lives of 2 to 4 year olds (291 females, 230 males, 8 gender not given) via an online survey completed by 529 mothers from across the United States. The results replicated previous findings on chronotypic differences in sleep-wake patterns and the development of morningness–eveningness in early childhood. The influence of chronotype on sleep habits, daily routines and schedules was also explored. At both bed and wake times, mothers of evening type (E-type) children were more likely to report challenges. For a while, morning type (M-type) children tended to fall asleep easily and wake themselves up in the morning, E-types were more likely to show bedtime resistance, wake in a negative mood and have conflicts with their parents. In the morning, mothers of M-type children often stuck to their normal routine on days when the child had to be somewhere at 7:00 am, whereas mothers of E-type children employed different strategies to get their child up and out the door. Bedtime routines and daily schedules also differed by chronotype. Individual differences in morningness–eveningness and their impact on sleep-wake patterns and social interactions are evident early on. A greater understanding of how they affect the lives of young children and their future development is needed.     

Wise “birds” follow their clock: The role of emotional intelligence and morningness–eveningness in diurnal regulation of mood

Emotional intelligence (EI) and morningness–eveningness (M-E) preference have been shown to influence mood states. The present article investigates the way in which these two constructs may interact, influencing morning and evening mood levels. A sample of 172 participants completed a multidimensional mood scale measuring energetic arousal (EA), tense arousal (TA), and hedonic tone at 7:00 and at 22:00. As expected, morning and evening types experienced higher EA at their preferred time of day; effects of M-E on other mood dimensions were weaker. EI was found to correlate with lower TA, but the association was stronger at 22:00, perhaps reflecting the role of EI in managing the social events characteristic for the evening hours. An interactive effect of EI and M-E was found for both diurnal changes and morning levels of EA. Namely, in individuals higher in EI, there appeared a more marked synchrony effect between chronotype and EA, which was absent in those low in EI; individuals higher in EI showed more pronounced diurnal changes in EA characteristic for their chronotype (i.e., higher EA at morning hours in morning chronotypes; higher EA at evening hours in evening chronotypes), while in participants low in EI, diurnal changes in EA were smaller. Moreover, the characteristic positive association between morningness and EA during morning hours was apparent only in those high in EI. These findings suggest that individual differences in circadian variation in mood reflect several factors, including an endogenous rhythm in energy, the distribution of social activities throughout the day, and the person’s awareness of their own energy level.     

Chronotype correlates with developmental index,intelligence and academic achievement: A study based on nationwide indicators

Chronotype or morningness–eveningness (M/E) is an individual trait with a biological basis. In this study, I analysed the relationship between M/E and nationwide available data, such as economic variables, school achievement, intelligence and conscientiousness, which is a personality trait. These variables have been chosen because, first, they are linked on the individual level with circadian preference, and, second these associations have been found based on meta-analyses, which gives these findings a high plausibility. In addition, economic status has also been proposed to be related to M/E. Higher developed countries showed a lower morningness, based on both, the ranking of countries as well as on the HDI value. Similarly, GNI was related to morningness, while higher intelligence and performance in PISA were related to eveningness. Conscientiousness was related to morningness, although the results failed the significance level marginally. When using IQ as a control variable in partial correlations, the relationship between GNI and morningness disappeared, as did the correlation between eveningness and PISA results.     

Morningness-eveningness and seasonality

The study aimed to elucidate previously observed associations between morningness–eveningness and seasonality by analysing their distinct aspects separately: morning affect (MA) and time-of-day preference, different seasonal types and patterns (winter, summer, etc.), the degree of seasonality and perceived negative impact of seasonality. Students from Warsaw (N = 522) completed the Seasonal Pattern Assessment Questionnaire and the Composite Scale of Morningness. Winter seasonality was related to lower MA, but unrelated to time-of-day preference. Global seasonality score was negatively associated with MA in winter seasonality, but not in other seasonality patterns, and unrelated to time-of-day preference. These associations remained significant after controlling for sex, age and season of assessment. It is concluded that winter seasonality is related to low MA, but not to time-of-day preference. The above results indicate that MA can be considered as an all year round indicator of proneness to winter seasonality and eventually to seasonal affective disorder. The results also suggest that MA and time-of-day preference should be analysed separately in future research on morningness–eveningness.     

Circadian preference and decision-making styles

The present study aimed to explore for the first time the relationship between circadian preference and different decision-making styles. In total, 501 young adults (330 females), with a mean age of 21.07 ± 1.99 years, took part in the study. The participants completed the reduced version of the morningness–eveningness questionnaire (rMEQ) and the general decision-making style inventory (GDMS). The rMEQ enabled to assess the circadian preference, with lower rMEQ scores pointing toward eveningness preference. The GDMS measured five decision-making styles: rational, intuitive, dependent, avoidant and spontaneous. Higher scores on each GDMS decision-making style reflect a higher prevalence of the corresponding style. A set of multiple regression analyses was performed with rMEQ score, gender and age as predictors together with each GDMS decision-making style as dependent variable. rMEQ score proved to be the only significant (negative) predictor of avoidant and spontaneous decision-making styles, i.e. lower rMEQ score (tendency toward eveningness) significantly predicted higher score at these decision-making styles. The present results suggest that eveningness preference is significantly related to avoidant and spontaneous decision-making styles in young adults. Such results will be discussed with reference to the effects of decision-making styles on decision-making in different types of workers and mental health.     

Positive and negative affect during the school day and its relationship to morningness–eveningness

We carried out a field study in adolescents in a German school to assess their actual affective state during the first and last lesson of a school day. Also, we wanted to assess if chronotype or sleep duration has an influence on affect. One hundred and nine girls and 110 boys participated in the study (mean age: 14.47). The composite scale of morningness (CSM) was used to assess morningness–eveningness and the positive and negative affect schedule (PANAS) was used for affect measurement. Sleep habits were assessed as both, habitual and actual sleep–wake rhythm. Positive affect (PA) was higher in the sixth lesson compared to the first one, but negative affect (NA) was not. CSM scores were positively correlated with PA during the first and last lesson. The correlation coefficient was higher in the first lesson of the day. NA was unrelated to CSM scores. Pupils with a shorter actual sleep duration had a higher NA. Habitual sleep duration was unrelated to affect measures. The results showed no synchrony effect; thus, evening types have still a lower PA in the last lesson than morning types. We emphasise the importance of mood and its relationship with morningness in school children, and we hypothesise that this may also have an influence on functioning during the school day.     

Perceived morningness–eveningness predicts academic adjustment and substance use across university,but social jetlag is not to blame

Past research has consistently found that evening-types typically report poorer academic adjustment and higher levels of substance use compared to morning-types. An important development within the morningness–eveningness and psychosocial adjustment literature has been the hypothesis that social jetlag (i.e. the asynchrony between an individual’s “biological” and “social” clocks) is one factor that may explain why evening-types are at a greater risk for negative psychosocial adjustment. Yet, only a handful of studies have assessed social jetlag. Furthermore, the few studies that have assessed social jetlag have done so only with concurrent data, and thus have not been able to determine the direction of effects among morningness–eveningness, social jetlag and psychosocial adjustment. To address this important gap in the literature, the present 3-year longitudinal study employed the use of a cross-lagged auto-regressive model to specifically examine the predictive role of perceived morningness–eveningness and social jetlag on two important indices of psychosocial adjustment among university students: academic adjustment and substance use. We also assessed whether there would be an indirect effect between perceived morningness–eveningness and psychosocial adjustment through social jetlag. Participants were 942 (71.5% female; M?=?19 years, SD?=?0.90) undergraduates at a mid-sized university in Southern Ontario, Canada, who completed a survey at three assessments, each one year apart, beginning in first-year university. Measures were demographics (age, gender and parental education), sleep problems, perceived morningness–eveningness, social jetlag, academic adjustment and substance use. As hypothesized, results of path analyses indicated that a greater perceived eveningness preference significantly predicted higher social jetlag, poorer academic adjustment and higher substance use over time. In contrast, we found no support for social jetlag as a predictor of academic adjustment and substance use, indicating that social jetlag did not explain the link between perceived morningness–eveningness and negative psychosocial adjustment. An important finding was the significant predictive effect of higher substance use on social jetlag over time. Results of the present study highlight the importance of employing a longitudinal framework within which to specifically determine the direction of effects among the study variables in order to validate proposed theoretical models that aim to guide our understanding of how perceived morningness–eveningness, social jetlag, academic adjustment and substance use relate to each other.     

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.     

Tendency toward eveningness is associated with unhealthy dietary habits

Subjects with higher preference for evening hours in daily activities (eveningness) have been repeatedly shown to practice adverse health behaviors as compared to those preferring morning hours (morningness). However, associations between chronotype and dietary intake have not been explored intensively. The authors explored whether the human chronotype is associated with food and nutrient intakes in a random sample of the population aged 25 to 74 yrs. The cross-sectional study included 4493 subjects from the National FINRISK 2007 Study. Chronotype was assessed using a shortened version of Horne and ?stberg's Morningness-Eveningness Questionnaire. Diet was assessed using a validated food frequency questionnaire. Associations between morningness-eveningness (ME) score and dietary intakes were analyzed by linear regression and difference between lowest (eveningness) and highest (morningness) ME score quintiles by Tukey's test. In the multivariable model, intakes of whole grain, rye, potatoes, and vegetables and roots decreased, whereas those of wine and chocolate increased with lower ME scores. Participants in the lowest ME score quintile consumed less fish (p 相似文献   

The role of temperament in the relationship between morningness–eveningness and mood

Apart from differences in circadian phase position, individuals with different morningness–eveningness levels vary in many more characteristics. Particularly consistent relationships have been observed between morningness–eveningness and mood. Eveningness has been associated with disadvantageous mood, e.g. depressiveness in healthy individuals, and mood disorders. A concept of social jetlag suggests that evening subjects function in less advantageous environments due to discrepancies between internal and social time (societies promote morning-oriented functioning), which results in their lowered mood. Individual temperament, as defined by the Regulative Theory of Temperament (RTT), refers to the capacity of the human organism to meet environmental requirements – the greater the capacity, the less negative impact of external conditions. Thus, the aim of this study is to determine which RTT traits are linked to both morningness–eveningness and mood dimensions and to test whether they account for the relationship between morningness–eveningness and mood. A sample of 386 university students (267 female) aged between 19 and 47 (M?=?21.15, SD?=?4.23) years completed the University of Wales Institute of Science and Technology (UWIST) Mood Adjective Check List, Morningness–Eveningness Questionnaire and Formal Characteristics of Behaviour – Temperament Inventory. Analyses revealed lower endurance (EN) and higher emotional reactivity (ER) related to eveningness as well as to lower hedonic tone (HT), energetic arousal (EA) and to higher tense arousal (TA). Moreover, eveningness was associated with lower HT, EA and higher TA. Among RTT traits, EN was most strongly related to eveningness, and mediation analyses revealed that this temperamental trait fully mediated the relationship between eveningness and the three mood dimensions. The remaining RTT traits did not provide more explanation of the association between morningness–eveningness and mood than EN itself. If subjects did not differ in EN, the association between morningness–eveningness and mood was absent. EN is discussed as a protective factor against negative consequences of social jetlag and particularly lowered mood in evening individuals.     

Clinical correlates of chronotypes in young persons with mental disorders

While important changes in circadian rhythms take place during adolescence and young adulthood, it is unclear how circadian profiles during this period relate to emerging mental disorders. This study aimed to: (i) characterise morningness–eveningness preference in young people with primary anxiety, depression, bipolar or psychotic disorders as compared to healthy controls, and (ii) to investigate associations between morningness–eveningness preference and the severity of psychiatric symptoms. Four hundred and ninety-six males and females aged between 12 and 30 years were divided into five groups according to primary diagnosis. The Hamilton Depression Rating Scale and the Brief Psychiatric Rating Scale were administered by a research psychologist and participants completed the Kessler Psychological Distress Scale and the Horne–Östberg Morningness–Eveningness Questionnaire (ME). ME scores were significantly lower (i.e. higher levels of “eveningness”) in all patient diagnosis subgroups compared to the control group. The psychosis group had higher ME scores than the depression and anxiety groups. Compared to the control group, the anxiety, depression and bipolar subgroups had a significantly higher proportion of “moderate evening” types, with a similar trend for the psychosis group. The proportion of “extreme evening” types was significantly higher in the anxiety and depression subgroups than in the control group. Lower ME scores correlated with worse psychological distress in males from the bipolar group. Lower ME scores correlated with higher depression severity in females with depression and in males with bipolar disorder. These results suggest that young persons with various mental disorders, especially those with affective disorders, present with a stronger “eveningness” preference and higher rates of evening chronotypes than healthy controls from the same age group. Later chronotypes were generally associated with worse psychological distress and symptoms severity. These associations were modulated by sex and primary diagnosis.     

Angry night birds: Emotionality,activity and sociability temperament in adolescent chronotypes

ABSTRACT

There is growing interest in personality profiles associated with morningness–eveningness to foster an understanding of the behaviors and mental states of chronotypes. This study aimed to analyze the domains of emotionality, activity and sociability (EAS) temperament in relation to morningness–eveningness in adolescents. A sample of 539 school pupils aged 13–19 years completed the EAS Temperament Survey, the Composite Scale of Morningness and the Munich Chronotype Questionnaire. Amongst the five EAS domains (emotionality-distress, emotionality-fearfulness, emotionality-anger, activity and sociability), greater emotionality-anger was related to eveningness, while greater emotionality-distress was related to lower social jet lag. The results suggest that evening chronotypes can be temperamentally inclined to anger. The possible mechanisms of this association are discussed.