Adrijana Košćec

Morningness–eveningness and sleep patterns of adolescents attending school in two rotating shifts

School system in which classes are scheduled 1 week in the morning and the other in the afternoon, and in which students rotate schedule every week, fosters sleep irregularity. In this study, we examined morningness–eveningness of adolescents who were involved in such schedule of school time and explored relationship between their circadian preferences and sleep characteristics. A large sample of 2287 students between the ages 11 and 18 years (52% girls) from 24 schools in Croatia was studied. The School Sleep Habits Survey was modified to enable differentiation of sleep patterns between the two school schedules and weekends. Two measures of ME were used: the Morningness–Eveningness Scale for Children (MESC) and mid-sleep time on weekends (MSFsc). Both measures showed a shift to eveningness starting between the ages 12 and 13 (MESC), or 13 and 14 (MSFsc). However, MESC demonstrated a plateau in the shift in older adolescent whereas MSFsc indicated further progress of phase delay. Significant differences in sleep timing and duration were found between three chronotype groups (Morning, Intermediate, and Evening). Generally, Evening types went to bed and woke up the latest in all situations. Their sleep duration was the shortest on school week with morning schedule. On weekends Morning types slept shorter than other two chronotype groups. On school week with afternoon schedule all chronotype groups slept close to the recommended 9 h. All three chronotype groups delayed their bedtimes and wake-up times, and extended their sleep in situations with fewer constraints on sleep timing (i.e. afternoon school schedule, and weekends versus morning school schedule). Expectedly, the evening types showed the greatest sleep irregularity. The findings of this study suggest that the Croatian school system fosters sleep irregularity, but provides more opportunity for fulfilling sleep need of all chronotype groups of adolescents. Age effects on morningness–eveningness observed in Croatian adolescent do not seem to be different from those observed in adolescents from other countries involved in a regular morning school schedule. Further studies are necessary to explore differences in the trend of shift towards eveningness found between the two measures of morningness–eveningness in this, as well as in other studies.

Morningness–eveningness across two student generations: would two decades make a difference?

Abstract The majority of morningness–eveningness questionnaires measure differences in preferred time of various daily activities. This study measured differences in actual habits during a 24-h period by means of the Student Morningness–Eveningness Questionnaire (SMEQ) developed by [ Sverko, B., Vidacek, S., & Kaliterna, L.J. (1979)]. Osobine licnosti I svakodnevne navike života [Personality characteristics and daily habits]. Revija za psihologiju, 9, 49–58.) . Data on actual daily habits were collected in the 1998 student generation (n=189) and compared to those of the generation examined in 1977 (n=128) that were published by Sverko et al. (1979) . The aims of the study were to examine psychometric properties of the SMEQ as well as to see if two student generations, 21 years apart, differed in their results on the questionnaire. Cronbach alpha coefficients were identical for both generations (0.77). Discrimination value of the items has not changed significantly, except on four questions. The results on the SMEQ were distributed normally in both generations and no significant differences were found between the mean values of the two groups. The results of the study testify to a high stability of the SMEQ as well as to stability of the morningness–eveningness dimension across two generations.

Is Atopy Related to Neuroticism, Stress, and Subjective Quality of Life?

Is Atopy Related to Neuroticism, Stress, and Subjective Quality of Life? Different psychosocial characteristics have been associated with allergic disorders. The aim of this study was to examine whether atopic constitution and reports of allergic symptoms were related to personality trait of neuroticism, exposure to stressful life events and estimates of quality of life. Atopy was determined by skin prick test and reports of nasal and pulmonary allergy-related symptoms. Actively working individuals of both genders took part in the study (n=145, age range: 20 to 66 years). The participants were divided in three groups. The first group was composed of those with negative skin prick test and without symptoms (n=57), the second of those with positive skin prick test but without symptoms (n=28), and the third of those with positive skin prick test and symptoms (n=60). The groups did not differ significantly in neuroticism, exposure to stressful life events, or quality of life. Women reported more pronounced neuroticism and anxiety, higher exposure to stressful life events, and were less satisfied with their environment than men. In our sample of active workers we found no association of neuroticism, exposure to stressful life events, and quality of life with atopy and allergic symptoms. Je li atopija povezana s neurotizmom, stresom i subjektivnom kvalitetom života? Dosadašnja istraživanja upućuju na međusobnu povezanost psihosocijalnih čimbenika i alergijskih poremećaja. Cilj ovog rada bio je ispitati jesu li atopijska konstitucija i alergijski simptomi povezani s neurotizmom kao osobinom ličnosti, izloženošću stresnim životnim događajima i subjektivnim procjenama kvalitete života. Stanje atopije određeno je s pomoću kožnog prick testa te izvještajima o nosnim i plućnim alergijskim simptomima. U ispitivanju su sudjelovale radno aktivne osobe obaju spolova (n=145) u dobi od 20 do 66 godina. Sudionici su podijeljeni u tri skupine. Jednu skupinu činili su sudionici s negativnim kožnim prick testom, koji nisu imali alergijske simptome (n=57). Drugu skupinu činili su sudionici s pozitivnim kožnim prick testom, ali koji nisu imali alergijske simptome (n=28). Treću skupinu činili su sudionici s pozitivnim kožnim prick testom koji su također imali i alergijske simptome (n=60). Skupine se nisu značajno razlikovale u neurotizmu, izloženosti stresnim životnim događajima i kvaliteti života. Kod žena je, neovisno o skupini, stupanj neurotizma i anksioznosti bio viši, izvještavale su o većoj izloženosti stresnim događajima te procijenile kvalitetu života u domeni okoliša nižom nego muškarci. Rezultati ovog ispitivanja ne upućuju na povezanost neurotizma, izloženosti stresu i kvalitete života s atopijom i alergijskim simptomima u skupini radno aktivnih osoba.

Circadian components in energy and tension and their relation to physiological activation and performance.

The purpose of the study was to examine validity of R. Thayers activation model regarding 24 h variations of two subjective dimensions of activation (Energy and Tension), and their 24 h relations with indices of physiological activation and performance efficiency. The participants of the study (n = 28 females) spent 26 h under controlled laboratory conditions. Self-ratings of subjective activation and measurements of oral temperature, electrodermal activity, and performance on a visual vigilance task were done every 4 h. Twenty-four-hour variations were examined by means of repeated measures analyses of variance and by group mean cosinor analyses before and after controlling for the data trends. Self-ratings on both dimensions of subjective activation showed significant 24 h variation. Energy showed both nonrhythmic and endogenously determined circadian variation, while 24 h variation of tension was dominantly nonrhythmic and most probably determined by exogenous factors. Significant 24 h covariation was found between energy and body temperature. A negative correlation between 24 h variation of energy and tension was also found. Considering low and intermediate levels of subjective activation established over the 24 h in this study, the association of the two dimensions of subjective activation did not prove to be consistent with the assumptions of Thayers model.

Parents Working Non-standard Schedules and Schools Operating in Two Shifts: Effects on Sleep and Daytime Functioning of Adolescents

This chapter examines how parental engagement in shift work affects sleep and daytime functioning in adolescents. The subject is introduced by an overview of biological and contextual factors that determine sleep in adolescents, and of parental influences on adolescents’ sleep. In a new study, we explored the effects of parents’ shift work on sleep quality and daytime functioning of adolescents. Data came from primary-school adolescents (11–14 years) and secondary-school adolescents (15–18 years) from Croatia (N = 1368), who were living with both employed parents, of whom both, one or neither were shift workers. The adolescents’ school schedule alternated between a week of morning classes and a week of afternoon classes. We did not find any negative effect of parents’ shift work on the sleep quality of adolescents. However, we found a significant negative effect on depressed mood for all adolescents (p < 0.01, eta = 0.10), and a negative effect on daytime sleepiness limited to secondary-school adolescents (p < 0.05, eta = 0.22). Sleepiness made the greatest contribution to depressed mood (β = 0.42, p < 0.001), but it did not cancel out the contribution of shift work (when both parents were shift workers) as a predictor of depressed mood (β = 0.09, p < 0.001). The results add to previous knowledge on the negative effects of parents’ engagement in shift work on the sleep patterns of adolescents. Implications for future studies are discussed.