Circadian Typology, Age, and the Alternative Five-Factor Personality Model in an Adult Women Sample

Chronotypes-personality behavioural syndromes in wild marine fish

Chronotypes, the individual differences in daily activity timing, have profound associations with numerous physiological processes. Despite this, the covariance between chronotypes and other aspects of an individual's behaviour has been infrequently explored in non-human animals. This study delves into individual's variation across four axes of personality in a controlled environment, utilising the pearly razorfish, a model species for fish chronotype studies. We identified behavioural types across the aggressiveness continuum and established behavioural syndromes amongst exploration, activity, and boldness, irrespective of body size and condition. Subsequent to this, the experimental subjects were reintroduced to their natural habitat and individually tracked using high-resolution technology to ascertain their chronotypes. Our results revealed that whilst the exploration-activity-boldness syndrome bore no correlation with chronotypes, a significant association was observed between aggressiveness and chronotype. Hence, individuals with later awakening times and rest onsets were more aggressive than their counterparts with earlier awakening times and rest onsets. This study provides pioneering evidence linking fish chronotypes with other behavioural traits, such as aggressiveness, suggesting that behavioural variation could be potentially linked to the individuals' variation in internal clocks and the environmental variables influencing their expression.

The Big Five personality traits and the fear of COVID-19 in predicting depression and anxiety among Japanese nurses caring for COVID-19 patients: A cross-sectional study in Wakayama prefecture

Recent studies have found a relationship between fear of COVID-19 and mental health problems. Medical workers caring for COVID-19 patients tend to suffer from mental health problems; however, the impact of their personality traits, in the form of mental problems like depression and anxiety in Japan is unclear. In this study, we investigated the risk of nurses' depression and anxiety, predicted by the fear of COVID-19 and the Big Five personality traits. A total of 417 nurses working in hospitals providing care to COVID-19 patients in Wakayama prefecture of the Kansai region participated in this study. The questionnaires comprised items on nurses' basic characteristics and three scales: the Fear of COVID-19 Scale 2020, the Big-Five Scale, and the Japanese version of the Hospital Anxiety and Depression Scale (HADS). Depression and anxiety in the HADS were set as dependent variables, and basic attributes, fear, and personality traits as independent variables; multivariate logistic regression analyses were conducted. The questionnaire, with no missing items was distributed from February to March 2021. Neuroticism (OR = 1.06, 95%CI = 1.03-1.09) was the only significant factor associated with the depression symptom, and both FCV-19S scores (OR = 1.16, 95%CI = 1.09-1.23) and neuroticism (OR = 1.09, 95%CI = 1.06-1.13) were the significant factors associated with anxiety. The Nagelkerke's R squared was 0.171 in the depression model and 0.366 in the anxiety model. Thus, it was found that it is necessary to support nurses' mental health by developing methods suitable to their personalities.

Eveningness, depression and cardiovascular reactivity to acute psychological stress: A mediation model

The psychological pathways linking depression to blunted cardiovascular reactivity (CVR) are still being elucidated. The purpose of the present study was to test whether the association between eveningness, a diurnal/sleep-wake preference and CVR would be mediated by depressive symptoms. One hundred and eighty-two healthy young adults completed measures of morningness/eveningness (the Morningness-Eveningness Questionnaire; MEQ-SA), depressive symptoms (Hospital Anxiety and Depression Scale; HADS) and had their blood pressure and heart rate monitored throughout a standardised stress testing protocol. Results indicated that depressive symptoms were negatively associated with systolic blood pressure (SBP) but not diastolic blood pressure (DBP) or heart rate (HR) reactions to the stress task. Eveningness was also negatively associated with both SBP and DBP, but not HR. As such, those who reported increased depressive symptomology, and higher scores on eveningness displayed a more blunted cardiovascular response. Furthermore, the latter relationship was mediated by depressive symptoms such that those reporting higher scores on eveningness also reported increased depressive symptomology and this resulted in blunted CVR for SBP. These findings withstood adjustment for several confounding factors including time of testing. In conclusion, the present findings highlight the importance of considering eveningness when looking at the depression-blunted CVR relationship.

A Public Dataset of 24-h Multi-Levels Psycho-Physiological Responses in Young Healthy Adults

Wearable devices now make it possible to record large quantities of physiological data, which can be used to obtain a clearer view of a person’s health status and behavior. However, to the best of our knowledge, there are no open datasets in the literature that provide psycho-physiological data. The Multilevel Monitoring of Activity and Sleep in Healthy people (MMASH) dataset presented in this paper provides 24 h of continuous psycho-physiological data, that is, inter-beat intervals data, heart rate data, wrist accelerometry data, sleep quality index, physical activity (i.e., number of steps per second), psychological characteristics (e.g., anxiety status, stressful events, and emotion declaration), and sleep hormone levels for 22 participants. The MMASH dataset will enable the investigation of possible relationships between the physical and psychological characteristics of people in daily life. Data were validated through different analyses that showed their compatibility with the literature.

Circadian Typology and Personality Dimensions of Croatian Students of Health-Related University Majors

The aim of this study was to determine the relationship between circadian preferences and personality dimensions among 712 students of three different majors from the Faculty of Medicine, Osijek: medical students (MD), nursing students (RN) and medical laboratory diagnostics students (MLD). For the measurement of personality dimensions, the IPIP50 Big-Five questionnaire was used. The circadian preference of students was assessed using the reduced morningness-eveningness questionnaire (rMEQ). Several significant results were observed and there was a significant difference in circadian preference among the three tested groups, with RN students scoring highest on the morningness scale and MLD students scoring the lowest. RN students scored significantly higher on agreeableness and conscientiousness than the other two groups. On the other hand, MD students scored higher on intellect than the MLD students. MLD students scored the lowest on emotional stability scales. Morning type students had higher conscientiousness and emotional stability scores. These results imply that circadian preference and personality traits are crucial elements of medical professionals' wellbeing. With this paper, we would like to raise awareness about common personality traits and adherence to certain circadian orientations in medical professionals as a motivation to introduce a more flexible view towards strict time and task divisions in everyday practice.

Personality Profile and Clinical Correlates of Patients With Substance Use Disorder With and Without Comorbid Depression Under Treatment

Background: Among patients with substance use disorder (SUD), major depressive disorder (MDD) is highly prevalent. Even though, personality plays an important role in treatment outcomes for individuals with SUD and SUD + MDD, few studies have explored personality characteristics in these samples. This study aims to describe personality for patients with SUD taking into account the comorbid MDD, using the Alternative Five Factor Model (AFFM). We also aim to compare SUD + MDD patients with population norms and to elucidate possible personality clinical correlates. Methods: For our study, 116 male patients undergoing for SUD treatment were divided in two groups: SUD only (N = 58) and SUD + MDD (N = 58). To examine personality, we used the Zuckerman-Kuhlman Personality Questionnaire and multiple analyses of covariance were performed to identify differences. In a first analysis, age was introduced as a covariate whereas in a second analysis the continuous variables that showed to have a discriminant value for the groups were added as covariates. Variables predicting the presence of dual diagnosis and personality clinical correlates were analyzed by logistic and linear regression models, respectively. We observed that patients with SUD + MDD show distinctive personality characteristics compared with patients with SUD only and population norms. Results: According to the AFFM, SUD + MDD patients are characterized by higher Neuroticism-Anxiety (positively associated to depressive symptoms) and Impulsivity; and by lower Parties and Friends. Moreover, the probability of having a dual depressive disorder was represented by the amount of medications and substances used. The preference for hard work and the energy self-reported levels (Work Activity trait) are linked to these clinical variables rather than to the presence/absence of a dual depressive disorder. Conclusions: Even when controlling clinical variables related to a higher probability of having a dual depressive disorder, the Neuroticism-Anxiety is a personality trait that strongly differentiates between SUD only and SUD + MDD patients. Further investigation is needed to explore the role of this personality trait as endophenotype in dual depressive men. Our results underline the importance of a dimensional understanding of personality and its clinical correlates among patients with SUD + MDD; this approach could provide us information on specific treatment strategies to improve the prognosis of patients.

The Effect of Chronotype on Psychophysiological Responses during Aerobic Self-Paced Exercises

It was hypothesized that an individual's chronotype might influence the response to physical activity at a given time of day. This study aimed to analyze the psychophysiological responses during a walking task at different times of day in individuals with different chronotypes. 46 students ( M age = 24.8yr., SD = 7.2) filled in the Morningness-Eveningness Questionnaire to determine chronotypes. Heart rate, walking time, and the rating of perceived exertion (RPE) were measured during two self-paced walking sessions: one in the morning (08:30) and one in the afternoon (15:30). A multivariate analysis of variance found a significant interaction between chronotype and time of day. The post hoc analysis showed a significant difference for RPE in the morning session, with evening types reporing a higher RPE compared with the morning types. The chronotype and the time of day when a physical task is undertaken can influence the RPE response, although it might not influence physiological or performance parameters. This has to be taken into account, because it can affect test reliability as well as possibly have a negative influence on the affective responses to a given task.

Circadian typology and the Alternative Five-Factor Model of personality

Two studies were carried out to explore the relationship between circadian typology and the Alternative Five-Factor Model of personality. In the first study, 379 participants (232 females) were administered the reduced version of the Morningness-Eveningness Questionnaire and the Zuckerman-Kuhlman Personality Questionnaire. Evening types reported higher impulsive sensation-seeking scores than morning and intermediate types, whereas morning types scored higher than evening types on activity factor. In the second study, the association between morningness and activity personality factor was verified through the objective-actigraphic monitoring of the rest-activity cycle. Actigraphy allowed us to operationalise both circadian typology, through the computing of midpoint of sleep (early values, expressed in hours and minutes, correspond to an advanced phase of the sleep/wake cycle), and activity factor by the means of motor activity recording. Fifty-one individuals (30 females) wore an actigraph on the nondominant wrist continuously for 1 week. A negative correlation was observed between midpoint of sleep and mean diurnal motor activity, demonstrating that an early phase of the sleep/wake cycle (i.e. morningness preference) was related to higher diurnal motor activity. Assessed both subjectively and objectively, the results of both studies highlight a significant relationship between morningness and activity personality factor.

Do different circadian typology measures modulate their relationship with personality? A test using the Alternative Five Factor Model

The relationship between personality and circadian typology shows some inconsistent results and it has been hypothesized that the model used to measure personality might have a moderating effect on this relationship. However, it has never been explored if this inconsistency was dependent on the questionnaire used to measure differences in circadian rhythms as well. We explored this issue in a sample of 564 university students (32% men; 19-40 years) using the Zuckerman-Kuhlman Personality Questionnaire, which is based on an evolutionary-biological approach, in combination with the Composite Scale of Morningness (CSM) and the reduced Morningness-Eveningness Questionnaire (rMEQ). Both questionnaires detected differences between circadian typologies in Sociability (highest in evening types; ET) and Impulsive Sensation-Seeking scales (highest in ET), while the CSM also detected differences in Activity (lowest in ET) and Aggression-Hostility (highest in ET). Further, both questionnaires detected differences between circadian typologies in the subscales General Activity (morning types [MT] higher than ET), Impulsivity (ET highest) and Sensation-Seeking (highest in ET). Differences between circadian typologies/groups in the subscales Parties (highest in ET) and Isolation Intolerance (lowest in MT) were only detected by the rMEQ. The CSM clearly separated evening types from neither and morning types while the rMEQ showed that neither types are not intermediate but closer to evening types in General Activity and Isolation Intolerance, and closer to morning types in Impulsive Sensation-Seeking, Parties, Impulsivity and Sensation Seeking. The obtained results indicate that the relationship between circadian typology and personality may be dependent on the instrument used to assess circadian typology. This fact may help to explain some of the conflicting data available on the relationship between these two concepts.

Circadian preference and trait impulsivity, sensation-seeking and response inhibition in healthy young adults

Circadian preference has been considered related with impulsivity. The purpose of the present study was to evaluate the relationship between circadian typology and impulsivity measured by the Barratt Impulsivity Scale (BIS), sensation-seeking measured by the Sensation Seeking Scale - Form V (SSS-V) and response inhibition elicited by the GO/NO-GO paradigm. A total of 503 Korean healthy college students (288 males and 215 females) completed the Composite Scale of Morningness (CSM) for circadian typology and the BIS and SSS-V for impulsivity and risk taking, respectively. A subset of 142 subjects additionally performed the computerized GO/NO-GO task for motor response inhibition. A significant association was found between the circadian typology of the CSM and impulsivity of the BIS and disinhibition of SSS-V. In addition, there was a difference in trend level between the circadian typology and response inhibition elicited by the GO/NO-GO test. Regarding circadian preference, evening types were significantly associated with higher impulsivity on the BIS, disinhibition on the SSS-V and lower rate of successful inhibition on the GO/NO-GO task compared to morning types. The present results showed significant relationships between circadian preference and impulsivity and sensation-seeking personality traits. In particular, our findings suggest that high impulsivity, disinhibition and impaired response inhibition are more related to evening types. Circadian preference might be associated with psychiatric problems interacting with some aspects of personality traits such as inhibitory control.

Social jetlag negatively correlates with academic performance in undergraduates

Discrepancies between sleep timing on workdays and weekends, also known as social jetlag (SJL), affect the majority of the population and have been found to be associated with increased health risk and health-impairing behaviors. In this study, we explored the relationship between SJL and academic performance in a sample of undergraduates of the Semmelweis University. We assessed SJL and other sleep-related parameters with the Munich ChronoType Questionnaire (MCTQ) (n = 753). Academic performance was measured by the average grade based on weekly test results as well as scores acquired on the final test (n = 247). The average mid-sleep point on free days in the Hungarian sample fits well the regression line plotted for longitudes within the Central European Time Zone and chronotypes, confirming that sunlight has a major impact on chronotype. Multivariate analysis showed negative effect of SJL on the weekly average grade (p = 0.028, n = 247) during the lecture term with its highly regular teaching schedules, while this association disappeared in the exam period (p = 0.871, n = 247) when students had no scheduled obligations (lower SJL). We also analyzed the relationship between the time of the weekly tests and academic performance and found that students with later sleep times on free days achieved worse in the morning (p = 0.017, n = 129), while the inverse tendency was observed for the afternoon test-takers (p = 0.10, n = 118). We did not find significant association between academic performance and sleep duration or sleep debt on work days. Our data suggest that circadian misalignment can have a significant negative effect on academic performance. One possible reason for this misalignment is socially enforced sleep times.

Aggression in Young Adults — A Matter of Short Sleep and Social Jetlag?

Evening orientation and sleep duration have been linked with aggression and problematic behaviors, but no study has used an explicit aggression questionnaire. The present study used the Buss-Perry Aggression Questionnaire based on physical aggression, verbal aggression, anger, and hostility, as well as questionnaires on the timing of sleep and sleep duration to assess this relationship in young adult men. The Composite Scale of Morningness was used to assess circadian preference; sleep-wake variables (wake time and sleep onset time on weekdays and on weekend days) were used to calculate midpoint of sleep, social jetlag, and sleep duration. Results indicated that sleep duration correlated negatively with verbal aggression, physical aggression, and anger. Short sleepers were more aggressive. Using multivariate analysis of variance, shorter sleep duration was a significant predictor of verbal aggression and anger. Concerning physical aggression, social jetlag also contributed to the model. Morningness-eveningness was associated with the hostility scale with eveningness related to higher hostility. Men scored higher than women in physical and verbal aggression.

Relationships among circadian typology, psychological symptoms, and sensation seeking

Recently, attention has been focused on the relationship among circadian typology, psychiatric symptoms, and personality traits. This study analyzes the influence of circadian typology on psychological distress, and the sensation-seeking personality trait. Five hundred seventeen college students (173 males), aged 17 to 30, answered the Composite Scale of Morningness (CSM), the General Health Questionnaire 28-item version (GHQ-28), and the Sensation Seeking Scale-V (SSS-V). The evening-type subjects in our sample scored higher than the neither- and morning- type in the GHQ-28 total score, as well as in the four subscales that composed it (Psychosomatic Symptoms, Anxiety and Insomnia, Social Dysfunction, and Severe Depression) (p<0.02 in all cases). The evening-type subjects also had a larger proportion of psychiatric cases than the other two circadian typologies (p<0.0001 in all cases). Moreover, the evening-type subjects obtained higher scores in the SSS-V total score and in the subscales of Disinhibition and Boredom Susceptibility (p<0.001 in all cases). A positive correlation was observed between the GHQ-28 and the SSS-V total scores in the total sample, but only for the evening-type group (r=0.217; p<0.027). In the evening group, several relations were also found between the subscales of the GHQ-28 and the subscales of the SSS-V (r>0.206; p<0.036). All these data point to a relationship between evening-type subjects and the level of psychological distress and the sensation-seeking personality trait. They also suggest that eveningness could be related to developing psychological distress and personality traits that could, in turn, be related to developing other problems, such as drug consumption.

Circadian typology: a comprehensive review

The interest in the systematic study of the circadian typology (CT) is relatively recent and has developed rapidly in the two last decades. All the existing data suggest that this individual difference affects our biological and psychological functioning, not only in health, but also in disease. In the present study, we review the current literature concerning the psychometric properties and validity of CT measures as well as individual, environmental and genetic factors that influence the CT. We present a brief overview of the biological markers that are used to define differences between CT groups (sleep-wake cycle, body temperature, cortisol and melatonin), and we assess the implications for CT and adjustment to shiftwork and jet lag. We also review the differences between CT in terms of cognitive abilities, personality traits and the incidence of psychiatric disorders. When necessary, we have emphasized the methodological limitations that exist today and suggested some future avenues of work in order to overcome these. This is a new field of interest to professionals in many different areas (research, labor, academic and clinical), and this review provides a state of the art discussion to allow professionals to integrate chronobiological aspects of human behavior into their daily practice.

Circadian preference and the big five: the role of impulsivity and sensation seeking

In the present study, the relationship between personality dimensions and Circadian Preference was evaluated using a structural equation modeling approach. Participants (N=390; 53.8% female, mean age: 26.8 ± 8.1 yrs) completed measures of Circadian Preference, Impulsivity, Sensation Seeking, and the Big Five factors. A mediation structural equation model assessed the direct and indirect effects of the Big Five factors on Circadian Preference. The results showed that Impulsivity and Sensation Seeking were significantly associated with Eveningness, whereas no significant direct effects of the Big Five traits were detected once the effects of Impulsivity and Sensation Seeking were taken into account.