Sleep problems and their implications from preschool to school age

Sleep plays a significant role in human functioning and wellbeing. It is of particular importance for young children, whose brains undergo significant developmental changes. This dissertation focuses on sleep problems among preschool-age children, the persistence of these problems until school age, and how they relate in establishing a behaviour and emotional wellbeing at school age. The importance of sleep quality to neural basis of sensory information processing and attention regulation among school age children was also assessed. According to the results of a population-based survey, sleep problems are very common in preschool-age children. Parents of almost half of the children surveyed reported frequent sleep problems most typically resistance to going to bed and difficulties falling asleep, followed by snoring, bruxism and sleep talking. Frequent bedtime resistance and difficulties falling asleep were also reported in a follow-up study of school-age children, as well as difficulty getting out of bed in the morning and early morning fatigue. Overall, the frequency of sleep difficulties decreased at school age. However, more than a third of the preschool-age children with sleep difficulties continued to have such problems at school age, when they were at the highest risk of experiencing comorbid emotional and behavioural problems. On the other hand, only a few children developed sleep problems at school age. Sleep quality among school-age children, measured objectively by means of actigraphy was associated with event-related brain potentials reflecting auditory information processing and attention regulation. Children with lower sleep quality had enhanced N2 and mismatch negativity responses, presumably reflecting hypersensitive reactivity to sounds, compared with children who sleep well. Sleep problems, therefore, appear to be a major challenge for the wellbeing of children at preschool and school-age. It appears from the results of this study that such problems are more common in younger age group, and that few children develop them later on. Therefore, preschool-age children and their families should be a major target group in identifying and treating sleep problems. It is essential to attend to such problems at preschool-age so as to prevent them from persisting over the longer term and adversely affecting the development of brain functions and behavioural and socio-emotional regulation.Unella on merkittävä rooli ihmisen toiminnan ja hyvinvoinnin kannalta. Erityisesti unen merkitys korostuu lapsilla, joiden aivot käyvät läpi merkittäviä kehitysvaiheita. Tässä väitöskirjassa tarkastellaan alle kouluikäisten lasten unihäiriöitä, niiden pysyvyyttä kouluikään saakka, yhteyttä psyykkiseen hyvinvointiin kouluiässä, sekä unen laadun merkitystä kouluikäisten lasten varhaisen tason sensorisen informaation käsittelyyn ja tarkkaavaisuuden suuntaamiseen aivotoiminnan tasolla. Väitöskirjan epidemiologisessa seurantatutkimuksessa havaittiin uniongelmien olevan hyvin yleistä alle kouluikäisillä lapsilla. Vanhemmat raportoivat toistuvia uniongelmia melkein puolella 3-6-vuotiaista lapsista. Yleisimmät ongelmat olivat nukkumaan menemisen vastustaminen ja nukahtamisvaikeudet, mutta myös kuorsaaminen, hampaiden narskuttaminen ja unessa puhuminen olivat yleisiä. Myös kouluiässä nukkumaan menoon liittyvä vastustus ja nukahtamisen vaikeudet olivat yleisiä, kuten myös aamuaikainen väsymys ja vaikeudet nousta sängystä. Kokonaisuudessaan univaikeudet vähenivät kouluiässä. Reilulla kolmanneksella 3-6-vuotiaista lapsista, joilla esiintyi uniongelmia alle kouluikäisinä, esiintyi uniongelmia vielä kouluiässä. Erityisesti näillä lapsilla oli erittäin suuri riski tunne-elämän ja käyttäytymisen ongelmien esiintymiseen univaikeuksien rinnalla. Sen sijaan vain harvalla lapsella uniongelmia alkoi esiintyä enää kouluiässä. Kouluikäisten lasten objektiivisesti mitatulla unen laadulla oli yhteys aivojen herätevastetutkimuksella mitattuun aivojen kuuloinformaation käsittelyyn ja tarkkaavaisuuden häiriöherkkyyteen. Lapsilla, joilla unen laatu oli heikentynyttä, esiintyi aivojen yliherkkään reagointiin viittaavaa aisti-informaation käsittelyn ja tarkkaavaisuuden säätelyn ongelmaa. Uniongelmien voidaan siis todeta olevan merkittävä haaste alle kouluikäisten ja kouluikäisten lasten hyvinvoinnille. Koska nyt tehdyn tutkimuksen perusteella alle kouluikäisillä uniongelmien esiintyvyys on selkeästi suurempaa kuin kouluikäisillä, tulisi neuvoloiden roolia univaikeuksien tunnistamisessa ja hoitamisessa kehittää entisestään. On tärkeää, että pienten lasten uniongelmat eivät muuttuisi pysyviksi, koska erityisesti pitkäkestoisina ne voivat haitata lapsen aivotoiminnan, käyttäytymisen ja sosioemotionaalisen säätelyn kehittymistä

Chronotype as self-regulation: morning preference is associated with better working memory strategy independent of sleep

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The Effects of Individual Characteristics of the Naval Personnel on Sleepiness and Stress during Two Different Watchkeeping Schedules

Background: Naval service can have a significant impact on the wellbeing of seafarers, and the operation of warships is highly dependent on the personnel on board. Nevertheless, there is a lack of knowledge concerning the impact of seafarers' individual characteristics on their wellbeing in a naval environment. Therefore, the aim of this study was to investigate individual characteristics of the naval personnel that may be associated with the amount of sleepiness, fatigue and stress responses experienced during shift work and irregular working hours in a naval environment. Methods: The study took place on a Finnish Defence Forces' Navy missile patrol boat on which 18 crewmembers served as study participants. The measurement periods lasted two separate weeks (seven days and six nights) during shift work with two different watchkeeping systems (4:4, 4:4/6:6). The onboard measurements consisted of the Karolinska Sleepiness Scale, salivary stress hormones, cognitive tests (Sustained Attention to Response Task and N-back Task) and heart rate variability. Results: Participants of older ages or with a longer history in naval service were associated with a greater amount of sleepiness, fatigue and stress responses on board. On the contrary, increased physical activity and a higher level of physical fitness, especially standing long jump, were associated with a lower amount of sleepiness, fatigue and fewer stress responses. In addition, an athletic body composition together with a healthy lifestyle may be beneficial, considering the stress responses on board. Conclusion: The present results are well in line with the previous literature regarding shift work and irregular working hours. The results highlight the importance of regular physical activity and good physical fitness during service in the naval environment

The Effects of Individual Characteristics of the Naval Personnel on Sleepiness and Stress during Two Different Watchkeeping Schedules

Background: Naval service can have a significant impact on the wellbeing of seafarers, and the operation of warships is highly dependent on the personnel on board. Nevertheless, there is a lack of knowledge concerning the impact of seafarers’ individual characteristics on their wellbeing in a naval environment. Therefore, the aim of this study was to investigate individual characteristics of the naval personnel that may be associated with the amount of sleepiness, fatigue and stress responses experienced during shift work and irregular working hours in a naval environment. Methods: The study took place on a Finnish Defence Forces’ Navy missile patrol boat on which 18 crewmembers served as study participants. The measurement periods lasted two separate weeks (seven days and six nights) during shift work with two different watchkeeping systems (4:4, 4:4/6:6). The onboard measurements consisted of the Karolinska Sleepiness Scale, salivary stress hormones, cognitive tests (Sustained Attention to Response Task and N-back Task) and heart rate variability. Results: Participants of older ages or with a longer history in naval service were associated with a greater amount of sleepiness, fatigue and stress responses on board. On the contrary, increased physical activity and a higher level of physical fitness, especially standing long jump, were associated with a lower amount of sleepiness, fatigue and fewer stress responses. In addition, an athletic body composition together with a healthy lifestyle may be beneficial, considering the stress responses on board. Conclusion: The present results are well in line with the previous literature regarding shift work and irregular working hours. The results highlight the importance of regular physical activity and good physical fitness during service in the naval environment.publishedVersionPeer reviewe

Cyber personalities as a target audience

Abstract Target audience analysis (TAA) is an essential part of any psychological operation. In order to convey a change in behaviour, the overall population is systematically segmented into target audiences (TAs) according to their expected responsiveness to different types of influence and messages, as well as their expected ability to behave in a desired way. The cyber domain poses a challenge to traditional TAA methods. Firstly, it is vast and complex, requiring effective algorithms to filter out relevant information within a meaningful timeframe. Secondly, it is constantly changing, representing a meshwork in formation, rather than a stable collection of TAA-specific data. The third challenge is that the target audience (TA) consists not of people, but of digital representations of people, whose true identity and characteristics cannot usually be verified. To address these challenges, the authors of this article suggest that the concept of TAA has to be revised for use in the cyber domain. Instead of trying to analyse physical people through the cyber interface, the authors have conceptualized an abstract entity whose physical identity might not be known, but whose behavioural patterns can be observed in the cyber environment. These cyber personalities, some of which are more or less intelligent algorithms, construct and share their interpretation of reality as well as carefully planned narratives in the digital environment. From the viewpoint of TAA, the only relevant quality of these entities is their potential ability to contribute to the objectives of a psychological operation. As a first step, this article examines the cyber domain through a five-layer structure and looks at what TAA-relevant data is available for analysis. The authors also present ways of analysing cyber personalities and their networks, in order to conduct a TAA that effectively supports psychological influence in the cyber domain. As a way of better utilizing the digital nature of cyber personalities, a concept of dynamic TAs is also introduced