Browsing by Subject "sleep"

Objective: Psychotic-like experiences (PLEs) are common in general population and exist in a continuum with clinical psychotic disorders. PLEs are associated with later psychotic and non-psychotic disorders as well as concurrent poorer functioning and distress. It has been well established that childhood trauma is a risk factor for later sleep disturbances, and both are predictors for higher occurrence of PLEs. However, these factors are rarely studied together and better understanding of the risk factors and underlying mechanisms behind PLEs is of clinical relevance to ensure better treatment and prevention of further disadvantages. Methods: The study population (N = 681) consisted of adolescent outpatients in psychiatric care in Finland. Results from self-reported questionnaires of childhood trauma, sleep quality, and PLEs were used in multiple linear regression models and the possible mediating effect of sleep quality between childhood trauma and PLEs was tested. Depressive and anxiety symptoms were later added as possible confounding variables. Results: Childhood trauma and sleep quality were both associated with hallucinations and delusions in primary analyses and there were indications of a small, partial mediating effect. However, adding depressive and anxiety symptoms to the models changed the mediating effects and sleep no longer appeared as an explanatory factor. Discussion: Depressive and anxiety symptoms appeared to explain the connection between childhood trauma and PLEs better than sleep quality. This could be due to overlap in symptomology that mask the possible effects of sleep or similar mechanisms behind examined variables that are also closely connected to depressive and anxiety symptoms.

Aims of the study. The aim of this study was to examine normative development of sleep patterns and circadian rhythmicity during adolescence. Previous studies have found that sleep duration shortens across the lifespan, and especially adolescents’ sleep timing shifts later due to physiological and psychological factors. Sleep patterns in adolescence are connected to individual’s endogenous circadian rhythms, usually measured by delayed melatonin secretion in the evening. There is a lack of understanding how sleep patterns are related to circadian body temperature rhythms during adolescence. Methods. This study was part of SleepHelsinki! cohort study of the Sleep & Mind Research Group. Adolescents’ sleep patterns were measured with actigraphies, whereas circadian body temperature was measured from the skin surface. Circadian temperature rhythmicity was inspected by circadian period length, the mesor of skin surface temperature and the amplitude of daily changes within the rhythm. Baseline measurements were measured from 215 (71.6 % girls) adolescents aged 16–18 years. At one-year follow-up, 156 (76.3 % girls) adolescents were measured again. Mixed models for repeated measures were used to examine changes over the year in sleep patterns and endogenous circadian temperature rhythm, separately for both girls and boys. Sex differences were tested with one-way variance analysis. Linear and ordinal regressions were used to predict sleep and circadian rhythm over the year. Results and conclusions. Over the year, adolescents’ sleep duration became longer during the week, while weekend sleep shortened. However, this change was only significant for girls. Sleep schedule became more delayed for both girls and boys during the week, as sleep onset, midpoint and offset occurred at a later time. Circadian rhythm changed for boys, as their average skin surface temperature increased, and their circadian temperature amplitude became smaller. Boys also had significantly lower circadian temperature amplitude than girls at the follow-up. Compared to boys, girls were 5.85 times more likely to have a high circadian temperature amplitude at the follow-up measurement. Changes in sleep length during the week was moderated by temperature amplitude, with higher circadian amplitude predicting sleep duration to become longer. Still, the likelihood to have long sleep duration was affected by past sleep duration.

The most typical symptoms of dementia include impairment of cognitive brain functions, such as memory and thinking. Most common forms of dementia include Alzheimer's disease, vascular dementia, Lewy body dementia, and frontotemporal dementia, which is caused by degeneration of the frontotemporal lobe. Alzheimer's disease is the most common form of dementia, covering about 75% of all the cases. The pathophysiology of Alzheimer's disease includes beta-amyloid plaques and tau proteins, which accumulate in the brain, and which have been linked to damage to nerve pathways and the appearance of the typical symptoms of the disease. The disorder is progressive, but the exact cause remains unknown. However, old age (>65 years), the APOE-4 gene, lifestyle, and some comorbidities, such as cardiovascular diseases, are considered risk factors. Even though extensive research has been conducted, there is currently no curative treatment for Alzheimer's disease. Sleep disorders can be both a symptom of Alzheimer's disease and a risk factor for the onset of the disorder. Therefore, the mechanisms of sleep and circadian rhythm are connected to the pathophysiology of Alzheimer's disease, for example through the glymphatic system that cleans the brain mainly during deep sleep. Many drugs for Alzheimer's disease have a recommended time of administration. The dosing time can be very important issue in terms of the effectiveness of the drug. According to a recent study, sleep and circadian rhythm have not been considered in most studies on new rapid-acting antidepressants. Therefore, we carried out an analogous systematic literature review for Alzheimer's disease and dementia. The aim of this study was to find out whether sleep and circadian rhythm have been considered in the most cited preclinical and clinical drug research articles for Alzheimer's disease and dementia during the last decade (2010–2020). In addition, it was examined which drug groups the studied compounds belonged to, and what was the sex distribution of the test subjects in the studies. The number of subjects was also determined from clinical studies, and the animal species from preclinical studies. The research articles analysed in the study were collected with a systematic literature review of Scopus database. The study found that most studies did not include any consideration of sleep or circadian rhythm. Most of the investigated compounds were small molecules, followed by supplements and herbs, and rest classified as biological drugs. Most of the clinical trials were relatively small studies with less than a hundred subjects or hundreds of subjects. Among the 100 most cited clinical research articles, there were 14 reanalyses and observational studies that were not included in this analysis of subject numbers. In clinical studies, most of the test subjects were usually female, while preclinical studies used commonly male animals. To conduct more open and reliable science in the future, drug research should pay more attention to the subjects’ sleep patterns, the time of drug administration, and reporting on these issues in the articles, which is usually part of the requirements of scientific journals. This could potentially narrow the translational gap between preclinical and clinical research.

Poor quality of sleep and the following health problems affecting daily life are in many cases caused by cognitive and physiological arousal resulted from a stressful event. Such stress detrimental to sleep may originate from psychosocial factors such as feelings of shame and social rejection. Our goal was to elucidate the impact of acute psychosocial stress occurring before bedtime on sleep macrostructure and the early night non-rapid eye movement sleep (NREMS). In addition, virtual reality solutions are emerging as options to simulate social threats in laboratory environments. We studied whether a virtual reality variation of a public speaking scenario was sufficient in producing a physiological stress response evident in heart rate variability (HRV) parameters. We compared two experimental groups of healthy young adults (n=34), which differed in the scenario completed within the virtual reality. The stress condition involved a public speaking simulation in front of an attentive virtual audience whereas the control condition involved listening to a neutral presentation in the same but empty virtual seminar room. The participants’ physiological responses were measured with a HRV monitor for 38 hours and the quality of sleep during the laboratory night following stress induction with electroencephalography (EEG). The examined early sleep period was divided into two separate cycles of NREMS, whose results were juxtaposed. For analysing frequency band activity during sleep, we processed the data from EEG with Fourier transformation to yield power spectral density values i.e. frequency activity values. Comparing the two conditions, we observed a distinct effect of stress both during the virtual public speaking scenario and in the subsequent early sleep in the participants from the stress group. We found a significant increase in heart rate and rising fluctuations in the LF/HF (HRV power spectrum high frequency/low frequency) ratio around the stress task period contrasting the results of the control condition, reflecting increased sympathetic tone in the stress group. In the following night, the percentage of stage N3 sleep significantly increased at the cost of N2 sleep during the first NREMS cycle in the stress condition, but this effect resolved in the second NREMS cycle where group differences were absent. As a key finding, the stress group exhibited higher beta frequency activity in proportion to delta activity throughout both cycles and sleep stages. This effect was significantly magnified in N3 sleep where the delta/beta activity ratio decreased in the stress group from cycle 1 to 2, indicating worsening quality of sleep as the night progressed. We reflected our results through a homeostatic point of view, where the increased high frequency beta activity at sleep onset and early sleep in the stress group might explain their increased N3 sleep duration in the first NREMS cycle. A stronger affinity for the important N3 sleep may be a sleep protective mechanism to counter the stress induced abnormally high frequency EEG activity at sleep onset and early sleep to ensure the restorative benefits of slow-wave activity.

Introduktion: För kort eller lång sömnduration, dålig sömnkvalitet och för lite motion har i tidigare studier visat sig påverka den psykiska hälsan negativt. En kombination av både bra sömn och tillräckligt med motion har kopplats med bättre psykiskt välbefinnande än enbart antingen bra sömn eller tillräckligt med motion. Psykisk ohälsa är associerat med sänkt livskvalitet, sämre funktionsförmåga, mer sjukledighet, större risk för förtidspension och ökad risk för vissa somatiska sjukdomar. Målsättning: Målet med denna undersökning är att få mer information om hur sömnduration, sömnkvalitet och motion är associerade med nedsatt psykiskt välbefinnande hos 18–39-åringar med en stor del av arbetslivet framför sig. Metoder: Undersökningsmaterialet (n = 4912) samlades in i Young Helsinki Health Study år 2017. Deltagarna var 18–39-åriga anställda vid Helsingfors stad (80% kvinnor, 20% män). Associationerna mellan sömnduration, sömnkvalitet, motion och nedsatt psykiskt välbefinnande granskades först var för sig. Efter detta granskades sömndurationens och sömnkvalitetens association med nedsatt psykiskt välbefinnande i olika fysiskt aktiva grupper. Analyserna anpassades för sociodemografiska faktorer, socioekonomiska faktorer, levnadsvanor och smärta. Resultat och slutsatser: En kort <6 timmars sömnduration var associerad med en ökad sannolikhet för nedsatt psykiskt välbefinnande. En sömnduration på ≥8 till <9 timmar var associerad med en mindre sannolikhet för nedsatt psykiskt välbefinnande. En lång sömnduration på ≥9 timmar var inte statistiskt signifikant associerad med en ökad sannolikhet för nedsatt psykiskt välbefinnande. Fysisk inaktivitet var inte statistiskt signifikant associerat med nedsatt psykiskt välbefinnande. Detta kan innebära att en större mängd motion krävs för att motionen ska ha en psykisk hälsoeffekt. Dålig sömnkvalitet var associerat med nedsatt psykiskt välbefinnande oberoende av fysiska aktivitetsnivån. En sömnduration på ≥8 till <9 timmar och bra sömnkvalitet var mest förmånliga för det psykiska välbefinnandet.

The heart rate of an individual varies all the time. This phenomenon is called heart rate variability. Both respiration and physical activity induce variations in heart rate. Heart rate variability can be assessed by studying electrical changes in the heart cycle. Electrical changes can be monitored by measuring ECG (electrocardiography). The main target of this study was to find out cow’s normal heart rate variability while they were awake, ruminating or sleeping. For this study, the heart rate of nine cows was recorded as well as their behavior during that time. Cows were monitored while they were sleeping, ruminating, standing or lying down. Four of the cows were from Finland and five of them from Sweden. From those nine cows, 543 one minute samples were obtained. This was the first time that cow’s heart rate was studied during their sleep cycle. The cows were not stressed in any way and their autonomic nervous system was not affected by drugs. One minute samples were analyzed. Samples were gathered by using a Matlab-based computer program, CowSS. All samples were checked visually, and all errors, for instance missing S-peaks or the errors caused by timing, were corrected. Statistical analysis was made by using a linear mixed effects model. According to the analysis, the best way to represent a cow’s heart rate variability is to use RMSSD-value. RMSSD-value describes the variations of adjacent intervals in different recordings. The result of this study show that during sleep the heart rate and the heart variability of cows are different from humans´. Cows´ sleep periods (NREM- and REM-sleep) are shorter and during REM-sleep the parasympathetic toning is stronger in cows. Cow is herbivore and prey for many predators, which may well explain the dominance of the parasympathetic system. Parasympathetic toning works faster than sympathetic toning, and this may give the cow a better chance to escape.

The importance of equine welfare has become more important in the last years. There is a need for welfare parameters, which help to define and measure the welfare of domestic horses. The importance of sleep on health and wellbeing is well-known in humans but has not yet been extensively studied in horses. It is known that horses sleep either non-REM-sleep or REM-sleep. Also, horses are able to partially sleep in a standing position. For REM-sleep they need to have muscle atony and lie down. Horses are easily disturbed while sleeping and many factors affect how much and how long horses spend sleeping. Horses are also able to postpone their REM-sleep for extensive periods of time, which directly effects their health and welfare. The aim of our study was to measure and analyze how the softness of the bedding in the lying areas affect the sleeping and resting behavior of horses. This thesis was part of the UNIHEPO initiative, which consisted of multiple studies around equine sleep. For our study we conducted a cross over study with sixteen (16) clinically healthy horses in the equine school Ylä-Savon ammattiopisto during fall 2022. The study included three treatments: the normal amount of bedding as the baseline, then thin (5 cm) bedding and thick (15 cm) of bedding. We recorded three periods: the baseline, and then two consecutive periods with half of the stalls having thick bedding and the other half thin. The duration of each treatment period was 21 days, respectively. We switched the treatments after the first period so that that each horse had both treatments. We recorded and analyzed the first two (2) and last two (2) nights of each period. The results were reported as seconds calculated from the median of the daily mean values. Only the data from the two treatments was analyzed for this thesis. The horses exhibited more resting behaviors and supported their necks longer in a sleeping position, when the bedding was thicker (p=0,002). There was no statistically significant difference between the treatments when lateral recumbency bout amounts or lying durations were analyzed, but the lying duration was longer. With thicker bedding the horses had a higher number of sternal recumbency bouts (p=0,013) and the bout duration was longer (p=0,001). Also, the total duration spent in sternal recumbency was higher on thicker bedding (p=0,002). Surprisingly we noticed rolling behavior after lying bouts almost solely on thicker bedding (p=0,004). There were also some tendencies for correlation between the height of the horses, lying bouts and bedding thickness. Our research provided us with valuable information on the factors affecting the sleeping and resting behavior of horses. At the same time the need for further research was highlighted. Still, our results reinforce the scientific knowledge, which is crucial in developing and promoting equine welfare.

Masennus on yleinen sairaus väestötasolla ja kansantaloudellisesti hyvin merkittävä, sillä masennus on merkittävä syy työkyvyttömyyseläkkeelle siirtymiseen. Unettomuus on yleinen oire masennuksen yhteydessä, mutta sen on havaittu olevan myös itsenäinen riskitekijä masennuksen puhkeamiselle. Unettomuus ei myöskään ole pelkkä oire, vaan usein itsenäinen liitännäissairaus masennuksen rinnalla. Masennuksen ja unettomuuden välillä on havaittu useita yhteisiä tekijöitä, vaikka nämä kaksi sairautta yhdistävää tarkkaa mekanismia ei vielä tiedetä. Tutkielman tarkoituksena on selvittää FinTerveys 2017 -tutkimuksen pohjalta masennuksen ja unettomuuden yleisyyttä suomalaisväestössä sekä selvittää regressiomallilla, assosioituvatko unettomuuteen liittyvät oireet masennukseen ja psyykkiseen oireiluun. Aineistosta havaitaan, että lääkärin toteamaa masennusta on 6,5 prosentilla ja usein koettua unettomuusoireilua 10 prosentilla. Usein koettu unettomuusoireilu on 5,47-kertaisesti (95 % CI = 4,05–7,40) yleisempää ihmisillä, joilla on lääkärin toteama masennus kuin ihmisillä, joilla masennusta ei ole. Lisäksi havaitaan, että kaikki huonosta unesta kielivät oireet (unettomuus, päiväväsymys, mielipide riittämättömästä unesta ja unilääkkeiden käyttö) näyttäisivät lisäävän riskiä masennukselle ja päiväväsymys assosioituu vahvimmin masennukseen. Tulokset vahvistavat unettomuuden yhteyttä masennukseen ja sen tärkeyttä, että unettomuuden taustalta on hyvä tunnistaa mahdolliset muut sairaudet, ja toisinpäin sitä, että masennuksen yhteydessä olevaa unettomuutta pitää tarkastella omana merkittävänä kokonaisuutenaan.

Sleep is one of the most vital functions of newborns and infants, and it is essential for neuronal network development. Therefore, long-term sleep disturbances have been associated with growth delays and behavioral disorders. Commonly reported infant sleep disturbances, such as night awakenings and difficulties falling asleep, cause distress to parents. Yet, the development of infant sleep in the home environment has not been fully elucidated due to lack of objective measurement parameters. In the current study, we assessed the feasibility of a motion sensor, attached to wearable pants, and ECG textile electrodes to monitor sleep-related respiration and heart rate of newborns and infants. First, we compared signals recorded by the motion sensor’s measurement channels to the standard respiratory piezo effort belt’s signal during daytime EEG recordings. According to our results, the motion sensor’s gyroscope proved to measure respiratory rate most accurately, while the ECG signal transmitted by the sensor was reliable in interpretable sections. We then provided wearable garments and smartphones to families with infants to assess overnight home-use. Our results indicate that different sleep states could likely be identified based on respiration fluctuation visible in the gyroscope’s signals. Moreover, the wearable system was considered practical and easy to use by the parents. Future studies should focus on validating the sensor with clinically approved measures, in order to train the algorithms to automatically identify different sleep-wake states. By doing so, the wearable sensor could provide information on natural infant sleep structure development over long time periods. Additionally, clinical validation of the sensor may result in the development of a companion diagnostic tool for infant cardiorespiratory and movement disorders.

Background Myoclonic twitches are bursts of jerky movements of the distal limbs that occur during REM-sleep (1). An earlier study conducted by Sokoloff et al. in 2020 hypothesized that myoclonic twitches could offer a crucial insight into the developmental status of a human infant’s nervous system (1). They assessed the patterning and the rate of twitching in 16 in term infants. Our study aimed to test whether the earlier conducted study and its findings could be repeated on a bigger scale. Materials & Methods The data for this study was collected from HUS (Helsinki University Hospital) Children’s Hospital’s Video-EEGs by collecting the data of all under one-year-old children that had been referred to video-EEG examinations between 9th May, 2019 - 20th May, 2020 and had their limbs visible whilst sleeping (133 sessions from 92 infants). The data was collected with the help of an EEG reader program named NicOne Reader by one annotator over the summer of 2020. The annotations were done with the accuracy of left foot, left hand, right foot, right hand and head. The median recording duration was 19.0 min (IQR: 13.58 to 27.24 min)(Range: from 1.5 to 210.5 min) and the average recording duration was 25.5 min. Results Our results showed that both the twitch frequency and the proportion of hand and feet clusters from all clusters grew in relation to age. In addition, twitching in the hands and the feet occurred much more often than twitching of the head or the face. Conclusions Like in Blomberg’s group’s study (1) our findings give promise that myoclonic twitching can be used to evaluate sensorimotor development in the future. Further studies are needed in order to form a universal database regarding myoclonic twitching and its relation to typical and atypical sensorimotor development.