Chronotype is determined by circadian rhythms,influenced by polygenic variations and environmental factors. Typically, chronotypes are categorized into morning-, intermediate-, and evening-types^([1]). Most cognitive ...Chronotype is determined by circadian rhythms,influenced by polygenic variations and environmental factors. Typically, chronotypes are categorized into morning-, intermediate-, and evening-types^([1]). Most cognitive functions follow daily and circadian rhythms, with the “synchronization effect” reflecting performance variations between optimal and non-optimal times based on an individual's chronotype.展开更多
BACKGROUND Dysfunctional beliefs about sleep may influence academic performance through their impact on sleep quality.Differences in chronotype can further moderate this relationship,particularly among students with i...BACKGROUND Dysfunctional beliefs about sleep may influence academic performance through their impact on sleep quality.Differences in chronotype can further moderate this relationship,particularly among students with irregular sleep patterns.AIM To examine the indirect effects of dysfunctional beliefs about sleep on academic performance through sleep quality while considering individual differences in chronotypes among medical students.METHODS The participants were categorized by chronotype and administered the Dysfunctional Beliefs and Attitudes about Sleep Scale and the Pittsburgh Sleep Quality Index and reported their grade point averages(GPAs).Mediation analysis was performed to examine indirect pathways through sleep quality.RESULTS Dysfunctional sleep beliefs did not directly affect academic success but indirectly impaired GPA via reduced sleep quality,especially in evening-type students.CONCLUSION Chronotype moderates the relationship between sleep quality and academic performance, highlighting the need for targeted cognitive interventions.展开更多
BACKGROUND Adolescents with an evening chronotype are at higher risk for mental health problems,such as depression and anxiety.However,the mechanisms underlying this relationship are not well understood.Sleep disturba...BACKGROUND Adolescents with an evening chronotype are at higher risk for mental health problems,such as depression and anxiety.However,the mechanisms underlying this relationship are not well understood.Sleep disturbances and impaired social functioning may mediate this association.AIM To examine the mediating roles of sleep quality and social functioning in the relationship between chronotype and mental health in adolescents.METHODS A cross-sectional survey was conducted among 381 adolescents(mean age 14.3 years;61.9%male)using the Morningness-Eveningness Questionnaire,Hamilton Depression Rating Scale,Hamilton Anxiety Scale,Pittsburgh Sleep Quality Index,and Social Disability Screening Schedule.Descriptive statistics,Pearson correlation analyses,and chain mediation analysis using the bootstrap method were performed.RESULTS Chronotype was significantly associated with both depression and anxiety.Sleep quality and social functioning significantly mediated these relationships.The indirect effect on depression was-0.52,accounting for 69.3%of the total effect.For anxiety, the indirect effect was -0.39, accounting for 79.3%. No significant direct effect of chronotype on depressionor anxiety was found after accounting for the mediators.CONCLUSIONSleep quality and social functioning mediate the association between chronotype and adolescent mental health.These findings highlight the importance of addressing sleep disturbances and social functioning impairments ininterventions aimed at improving mental well-being among adolescents with evening chronotypes.展开更多
Service members are at risk for sleep and psychological conditions affecting their readiness. Chronotype(“morningness”or “eveningness”) is strongly associated with sleep, health and performance. The objective of t...Service members are at risk for sleep and psychological conditions affecting their readiness. Chronotype(“morningness”or “eveningness”) is strongly associated with sleep, health and performance. The objective of this study was to examine associations between validated measures of chronotype and sleep quality, daytime functioning, alertness,and symptoms of depression, anxiety, and post-traumatic stress disorder(PTSD) in US service members(n=298).Although predominantly young males(who skew toward eveningness in civilian populations), these Sailors skewed toward morningness(35.6% morning, 51.3% intermediate). Eveningness was associated with symptoms of depression and PTSD(P<0.01), less time in bed(P<0.05), more sleep disruption(P<0.01), and poorer daytime functioning and alertness(P<0.05). Evening types were less likely to consider sleep important for performance(P<0.05). To maximize service member readiness, schedules should be aligned with endogenous rhythms, whenever possible, and evening chronotypes may benefit from targeted interventions. Chronotype should be examined alongside health and readiness in service members.展开更多
Circadian rhythm is an endogenous rhythmic behavior of organisms which can be entrained by daily light–dark cycles.The timing of human sleep-cycle is regulated by endogenous circadian rhythm and homeostatic processes...Circadian rhythm is an endogenous rhythmic behavior of organisms which can be entrained by daily light–dark cycles.The timing of human sleep-cycle is regulated by endogenous circadian rhythm and homeostatic processes. Light exposure affects both sleep timing and circadian rhythm. Now humans can extend lighting time by turning on artificial lights and wake up time is usually triggered by alarm clocks to meet social schedules. This modern lifestyle is believed to be related with a temporal mismatch between sleep and circadian rhythmicity(social jet-lag) and insufficient sleep, which lead to ill mental and physical health outcomes. At present, the impacts of self-selection of light exposure and social constrains on sleep timing is far from clear. According to preferred sleep-wake schedule, there are three different chronotypes. In this paper, we apply a mathematical model to get a quantitative comparison of sleep timing of people with different chronotypes with the effects of modern light consumption and social constrains. The results show that the prolonged day light and evening light exposure both delay preferred sleep timing with the sleep duration almost unchanged. People of evening-type or with longer intrinsic periods are most expected to be vulnerable to evening light. Increasing light exposure can offset the effect of evening light to some extent, but it is most difficult for evening-type people. Social constrains cause the largest social jet-lag in people of evening-type, which increases with evening light intensity or intrinsic periods. Morning-type people's sleep symptoms worsens, while that of evening-type people improves with age. This study provides a theoretical reference for preventing and treating sleep disorder and social jet-lag for individuals with different chronotypes.展开更多
We investigated factors contributing to smartphone dependence. To 196 medical university students, we administered a set of self-reporting questionnaires designed to evaluate demographic characteristics, smartphone de...We investigated factors contributing to smartphone dependence. To 196 medical university students, we administered a set of self-reporting questionnaires designed to evaluate demographic characteristics, smartphone dependence, chronotype, and depressive state. Smartphone dependence was evaluated using the Wakayama Smartphone-Dependence Scale (WSDS) with 3 subscales: Subscale 1, immersion in Internet communication;Subscale 2, using a smartphone for extended periods of time and neglecting social obligations and other tasks;Subscale 3, using a smartphone while doing something else and neglect of etiquette. Multiple regression analyses revealed that living in a family, eveningness, and presence of depression were associated with Subscale 1, that living in a family and eveningness were also associated with Subscale 2, and that being a man was associated with Subscale 3. These findings suggest that smartphone dependence can be predicted by factors such as gender, mode of residence, chronotype, or depressive state.展开更多
Depression is a widespread and debilitating mental health disorder affecting millions globally.Chronotype has been increasingly recognized as a significant factor associated with depression.This review aims to compreh...Depression is a widespread and debilitating mental health disorder affecting millions globally.Chronotype has been increasingly recognized as a significant factor associated with depression.This review aims to comprehensively dissect the role of chronotype in depression,providing insights into the underlying mechanisms linking chronotype to depression,as well as the potential therapeutic implications.Converging evidence indicates that evening chronotype is notably associated with an elevated risk of depression,more severe symptoms,and a higher rate of suicidality,while morning chronotype may exert a protective effect.These findings highlight that chronotype plays a crucial role in the development,manifestation,and management of depression.Nevertheless,some methodological issues of the existing studies(e.g.,reliance on self-reported chronotype assessments)should be noted and discussed.Further investigations are warranted to elucidate the intricate mechanisms underlying the relationship between chronotype and depression,establish causal links,and optimize the clinical application of chronotype-based interventions for depression.展开更多
Affective disorders are often accompanied by circadian rhythm disruption and the major symptoms of mental illness occur in a rhythmic manner.Chronotype,also known as circadian preference for rest or activity,is believ...Affective disorders are often accompanied by circadian rhythm disruption and the major symptoms of mental illness occur in a rhythmic manner.Chronotype,also known as circadian preference for rest or activity,is believed to exert a substantial influence on mental health.Here,we review the connection between chronotypes and affective disorders,and discuss the potential underlying mechanisms between these two phenomena.展开更多
Purpose:Individual chronotypes are reported to be closely associated with mood,health status,and even disease progression.However,no reports of chronotype distribution in the Chinese population have been made availabl...Purpose:Individual chronotypes are reported to be closely associated with mood,health status,and even disease progression.However,no reports of chronotype distribution in the Chinese population have been made available to date.Methods:We performed a chronotype survey using the classic Morningness–Eveningness Questionnaire both online and offline.The webpage-based online survey was distributed via a social network application on mobile phones.The offline survey was distributed to local primary and middle schools.A total of 9476 questionnaires were collected,of which 8395 were valid.The mean age of the participants was 30.38±11.47 years,and 37.38%were male.Results:Overall,the Chinese chronotypes showed a near-normal distribution with a slight shift toward eveningness.When analyzed in different age groups,the overall Chinese population was shown to be"latest"in their early twenties.In the young population,two significant points of change in chronotype were identified at the ages of 10 and 16 years.The chronotype composition remained relatively stable during early adulthood(from 17 to 28 years of age).Conclusion:This study generated the first overview of chronotype distribution in the Chinese population and will serve as essential background data for future studies.展开更多
Synchrony of biological processes with environmental cues developed over millennia to match growth, reproduction and senescence. This entails a complex interplay of genetic, metabolic, chemical, light, hormonal andhed...Synchrony of biological processes with environmental cues developed over millennia to match growth, reproduction and senescence. This entails a complex interplay of genetic, metabolic, chemical, light, hormonal andhedonistic factors across life forms. Sleep is one of the most prominent rhythms where such a match is established. Over the past 100 years or so, it has been possible to disturb the synchrony between sleep-wake cycle and environmental cues. Development of electric lights, shift work and continual accessibility of the internet has disrupted this match. As a result, many noncommunicable diseases such as obesity, insulin resistance, type 2 diabetes, coronary artery disease and malignancies have been attributed in part to such disruption. In this presentation a review is made of the origin and evolution of sleep studies, the pathogenic mediators for such asynchrony, clinical evidence and relevance and suggested management options to deal with the disturbances.展开更多
Sleep has attracted extensive attention due to its significance in health.However,its association with erectile dysfunction(ED)is insufficiently investigated.To investigate the potential causal links between sleep tra...Sleep has attracted extensive attention due to its significance in health.However,its association with erectile dysfunction(ED)is insufficiently investigated.To investigate the potential causal links between sleep traits(insomnia,sleep duration,and chronotype)and ED,this study was performed.The single-nucleotide polymorphisms(SNPs)associated with insomnia,sleep duration,and chronotype were retrieved from previous genome-wide association studies(GWAS).A conventional two-sample Mendelian randomization(MR)was used to estimate the causal links between sleep traits and ED.The summary statistics of ED were from individuals of European ancestry(6175 cases vs 217630 controls).As shown by the random effect inverse-variance-weighting(IVW)estimator,genetically predicted insomnia was causally associated with a 1.15-fold risk of ED(95%confidence interval:1.07-1.23,P<0.001).Sleep duration and morningness were not causally associated with ED,as indicated by the IVW(all P>0.05).These findings were consistent with the results of sensitivity analyses.Based on genetic data,this study provides causal evidence that genetically predicted insomnia increases the risk of ED,whereas sleep duration and chronotype do not.展开更多
On the basis of Gabriel Zoran＇s theory of spatial pattern, particularly the 3 levels of world reconstruction, the pattern of narrative space in Ursula Le Guin＇s The Left Hand of Darkness is figured out. A spatial pa...On the basis of Gabriel Zoran＇s theory of spatial pattern, particularly the 3 levels of world reconstruction, the pattern of narrative space in Ursula Le Guin＇s The Left Hand of Darkness is figured out. A spatial pattern of Tai Chi diagram is established on the textual level, the chronotopic level and the topographical level simultaneously. To demonstrate the validity of this Tai Chi spatial pattern, the stylistic feature of ＂shfgrethor＂ is analyzed in accordance with the Tai Chi spatial pattern, thereby proves the pattern＇s reliability. As an effect, this Tai Chi spatial pattern functions as Le Guin＇s fitting shape of carrier bag in science fiction containing both mythology and realist elements into a cyclic narrative.展开更多
基金supported by Zhongda Hospital Affiliated to Southeast University,Jiangsu Province High-Level Hospital Construction Funds(Grant No.GSP-LCYJFH07)。
文摘Chronotype is determined by circadian rhythms,influenced by polygenic variations and environmental factors. Typically, chronotypes are categorized into morning-, intermediate-, and evening-types^([1]). Most cognitive functions follow daily and circadian rhythms, with the “synchronization effect” reflecting performance variations between optimal and non-optimal times based on an individual's chronotype.
文摘BACKGROUND Dysfunctional beliefs about sleep may influence academic performance through their impact on sleep quality.Differences in chronotype can further moderate this relationship,particularly among students with irregular sleep patterns.AIM To examine the indirect effects of dysfunctional beliefs about sleep on academic performance through sleep quality while considering individual differences in chronotypes among medical students.METHODS The participants were categorized by chronotype and administered the Dysfunctional Beliefs and Attitudes about Sleep Scale and the Pittsburgh Sleep Quality Index and reported their grade point averages(GPAs).Mediation analysis was performed to examine indirect pathways through sleep quality.RESULTS Dysfunctional sleep beliefs did not directly affect academic success but indirectly impaired GPA via reduced sleep quality,especially in evening-type students.CONCLUSION Chronotype moderates the relationship between sleep quality and academic performance, highlighting the need for targeted cognitive interventions.
文摘BACKGROUND Adolescents with an evening chronotype are at higher risk for mental health problems,such as depression and anxiety.However,the mechanisms underlying this relationship are not well understood.Sleep disturbances and impaired social functioning may mediate this association.AIM To examine the mediating roles of sleep quality and social functioning in the relationship between chronotype and mental health in adolescents.METHODS A cross-sectional survey was conducted among 381 adolescents(mean age 14.3 years;61.9%male)using the Morningness-Eveningness Questionnaire,Hamilton Depression Rating Scale,Hamilton Anxiety Scale,Pittsburgh Sleep Quality Index,and Social Disability Screening Schedule.Descriptive statistics,Pearson correlation analyses,and chain mediation analysis using the bootstrap method were performed.RESULTS Chronotype was significantly associated with both depression and anxiety.Sleep quality and social functioning significantly mediated these relationships.The indirect effect on depression was-0.52,accounting for 69.3%of the total effect.For anxiety, the indirect effect was -0.39, accounting for 79.3%. No significant direct effect of chronotype on depressionor anxiety was found after accounting for the mediators.CONCLUSIONSleep quality and social functioning mediate the association between chronotype and adolescent mental health.These findings highlight the importance of addressing sleep disturbances and social functioning impairments ininterventions aimed at improving mental well-being among adolescents with evening chronotypes.
基金supported by the Department of Defense Congressionally Directed Medical Research Programs,Joint Program Committee-5 Early Assessment and Intervention Working Group(N1634)。
文摘Service members are at risk for sleep and psychological conditions affecting their readiness. Chronotype(“morningness”or “eveningness”) is strongly associated with sleep, health and performance. The objective of this study was to examine associations between validated measures of chronotype and sleep quality, daytime functioning, alertness,and symptoms of depression, anxiety, and post-traumatic stress disorder(PTSD) in US service members(n=298).Although predominantly young males(who skew toward eveningness in civilian populations), these Sailors skewed toward morningness(35.6% morning, 51.3% intermediate). Eveningness was associated with symptoms of depression and PTSD(P<0.01), less time in bed(P<0.05), more sleep disruption(P<0.01), and poorer daytime functioning and alertness(P<0.05). Evening types were less likely to consider sleep important for performance(P<0.05). To maximize service member readiness, schedules should be aligned with endogenous rhythms, whenever possible, and evening chronotypes may benefit from targeted interventions. Chronotype should be examined alongside health and readiness in service members.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11672177)。
文摘Circadian rhythm is an endogenous rhythmic behavior of organisms which can be entrained by daily light–dark cycles.The timing of human sleep-cycle is regulated by endogenous circadian rhythm and homeostatic processes. Light exposure affects both sleep timing and circadian rhythm. Now humans can extend lighting time by turning on artificial lights and wake up time is usually triggered by alarm clocks to meet social schedules. This modern lifestyle is believed to be related with a temporal mismatch between sleep and circadian rhythmicity(social jet-lag) and insufficient sleep, which lead to ill mental and physical health outcomes. At present, the impacts of self-selection of light exposure and social constrains on sleep timing is far from clear. According to preferred sleep-wake schedule, there are three different chronotypes. In this paper, we apply a mathematical model to get a quantitative comparison of sleep timing of people with different chronotypes with the effects of modern light consumption and social constrains. The results show that the prolonged day light and evening light exposure both delay preferred sleep timing with the sleep duration almost unchanged. People of evening-type or with longer intrinsic periods are most expected to be vulnerable to evening light. Increasing light exposure can offset the effect of evening light to some extent, but it is most difficult for evening-type people. Social constrains cause the largest social jet-lag in people of evening-type, which increases with evening light intensity or intrinsic periods. Morning-type people's sleep symptoms worsens, while that of evening-type people improves with age. This study provides a theoretical reference for preventing and treating sleep disorder and social jet-lag for individuals with different chronotypes.
文摘We investigated factors contributing to smartphone dependence. To 196 medical university students, we administered a set of self-reporting questionnaires designed to evaluate demographic characteristics, smartphone dependence, chronotype, and depressive state. Smartphone dependence was evaluated using the Wakayama Smartphone-Dependence Scale (WSDS) with 3 subscales: Subscale 1, immersion in Internet communication;Subscale 2, using a smartphone for extended periods of time and neglecting social obligations and other tasks;Subscale 3, using a smartphone while doing something else and neglect of etiquette. Multiple regression analyses revealed that living in a family, eveningness, and presence of depression were associated with Subscale 1, that living in a family and eveningness were also associated with Subscale 2, and that being a man was associated with Subscale 3. These findings suggest that smartphone dependence can be predicted by factors such as gender, mode of residence, chronotype, or depressive state.
基金Supported by the Science and Technology Projects in Guangzhou,China,No.2025A03J4256 and No.2025A03J4239.
文摘Depression is a widespread and debilitating mental health disorder affecting millions globally.Chronotype has been increasingly recognized as a significant factor associated with depression.This review aims to comprehensively dissect the role of chronotype in depression,providing insights into the underlying mechanisms linking chronotype to depression,as well as the potential therapeutic implications.Converging evidence indicates that evening chronotype is notably associated with an elevated risk of depression,more severe symptoms,and a higher rate of suicidality,while morning chronotype may exert a protective effect.These findings highlight that chronotype plays a crucial role in the development,manifestation,and management of depression.Nevertheless,some methodological issues of the existing studies(e.g.,reliance on self-reported chronotype assessments)should be noted and discussed.Further investigations are warranted to elucidate the intricate mechanisms underlying the relationship between chronotype and depression,establish causal links,and optimize the clinical application of chronotype-based interventions for depression.
基金supported by grants from the Natural Science Foundation of China(No.31930021,No.31671360)to Luoying ZhangChina Postdoctoral Science Foundation(No.2018M632826)to Qiang Gao.
文摘Affective disorders are often accompanied by circadian rhythm disruption and the major symptoms of mental illness occur in a rhythmic manner.Chronotype,also known as circadian preference for rest or activity,is believed to exert a substantial influence on mental health.Here,we review the connection between chronotypes and affective disorders,and discuss the potential underlying mechanisms between these two phenomena.
基金supported by grants from the National Natural Science Foundation of China(No.31630091 awarded to Ying Xu,No.81600380 awarded to F.Z.,No.31600958 awarded to Z.L.)National Center for International Research(No.2017B01012)
文摘Purpose:Individual chronotypes are reported to be closely associated with mood,health status,and even disease progression.However,no reports of chronotype distribution in the Chinese population have been made available to date.Methods:We performed a chronotype survey using the classic Morningness–Eveningness Questionnaire both online and offline.The webpage-based online survey was distributed via a social network application on mobile phones.The offline survey was distributed to local primary and middle schools.A total of 9476 questionnaires were collected,of which 8395 were valid.The mean age of the participants was 30.38±11.47 years,and 37.38%were male.Results:Overall,the Chinese chronotypes showed a near-normal distribution with a slight shift toward eveningness.When analyzed in different age groups,the overall Chinese population was shown to be"latest"in their early twenties.In the young population,two significant points of change in chronotype were identified at the ages of 10 and 16 years.The chronotype composition remained relatively stable during early adulthood(from 17 to 28 years of age).Conclusion:This study generated the first overview of chronotype distribution in the Chinese population and will serve as essential background data for future studies.
文摘Synchrony of biological processes with environmental cues developed over millennia to match growth, reproduction and senescence. This entails a complex interplay of genetic, metabolic, chemical, light, hormonal andhedonistic factors across life forms. Sleep is one of the most prominent rhythms where such a match is established. Over the past 100 years or so, it has been possible to disturb the synchrony between sleep-wake cycle and environmental cues. Development of electric lights, shift work and continual accessibility of the internet has disrupted this match. As a result, many noncommunicable diseases such as obesity, insulin resistance, type 2 diabetes, coronary artery disease and malignancies have been attributed in part to such disruption. In this presentation a review is made of the origin and evolution of sleep studies, the pathogenic mediators for such asynchrony, clinical evidence and relevance and suggested management options to deal with the disturbances.
基金This work was supported by the Natural Science Foundation of China(No.81871147 and No.82071639)the Sichuan Science and Technology Program(No.2022YFS0028 and No.2022YFS0134).
文摘Sleep has attracted extensive attention due to its significance in health.However,its association with erectile dysfunction(ED)is insufficiently investigated.To investigate the potential causal links between sleep traits(insomnia,sleep duration,and chronotype)and ED,this study was performed.The single-nucleotide polymorphisms(SNPs)associated with insomnia,sleep duration,and chronotype were retrieved from previous genome-wide association studies(GWAS).A conventional two-sample Mendelian randomization(MR)was used to estimate the causal links between sleep traits and ED.The summary statistics of ED were from individuals of European ancestry(6175 cases vs 217630 controls).As shown by the random effect inverse-variance-weighting(IVW)estimator,genetically predicted insomnia was causally associated with a 1.15-fold risk of ED(95%confidence interval:1.07-1.23,P<0.001).Sleep duration and morningness were not causally associated with ED,as indicated by the IVW(all P>0.05).These findings were consistent with the results of sensitivity analyses.Based on genetic data,this study provides causal evidence that genetically predicted insomnia increases the risk of ED,whereas sleep duration and chronotype do not.
文摘On the basis of Gabriel Zoran＇s theory of spatial pattern, particularly the 3 levels of world reconstruction, the pattern of narrative space in Ursula Le Guin＇s The Left Hand of Darkness is figured out. A spatial pattern of Tai Chi diagram is established on the textual level, the chronotopic level and the topographical level simultaneously. To demonstrate the validity of this Tai Chi spatial pattern, the stylistic feature of ＂shfgrethor＂ is analyzed in accordance with the Tai Chi spatial pattern, thereby proves the pattern＇s reliability. As an effect, this Tai Chi spatial pattern functions as Le Guin＇s fitting shape of carrier bag in science fiction containing both mythology and realist elements into a cyclic narrative.
