scholarly journals Circadian modulation of human sleep spindle frequency

2021 ◽  
Author(s):  
Robert Bodizs ◽  
Csenge G Horvath ◽  
Orsolya Szalardy ◽  
Peter P Ujma ◽  
Peter Simor ◽  
...  
Keyword(s):  
Age Groups ◽  
Frequency Resolution ◽  
Sleep Cycle ◽  
Sleep Spindles ◽  
Sleep Spindle ◽  
Sleep Regulation ◽  
Age Related ◽  
Sleep Homeostasis ◽  
Resolution Analysis ◽  
The Individual

Homeostatic and circadian processes play a pivotal role in determining sleep structure, timing and quality. In sharp contrast with the wide accessibility of the EEG index of sleep homeostasis, an electrophysiological measure of the circadian modulation of sleep is still non-available. As a consequence, the circadian component of sleep regulation is assumed, but not assessed in routine polysomnographic records. Available evidence suggests that sleep spindle frequencies are markers of the circadian modulation of sleep. In order to test the above assumption, the Budapest-Munich database of sleep records (N = 251), as well as an afternoon nap sleep record database (N = 112) were analysed by the Individual Adjustment Method of sleep spindle analysis. Slow and fast sleep spindle frequencies were characterized by U-shaped overnight dynamics, with highest values in the first and the fourth-to-fifth sleep cycle and the lowest values in the middle of the sleeping period (cycles 2-3). Age-related attenuation of sleep spindle deceleration was evident. Estimated phases of the nadirs in sleep spindle frequencies were advanced in children as compared to other age groups. Additionally, nap sleep spindles were faster than night sleep spindles (0.57 and 0.39 Hz difference for slow and fast types, respectively). Our findings suggest that the circadian modulation of sleep is measurable by a fine frequency resolution analysis of sleep spindles. Moreover, age-related attenuation of circadian sleep modulation can be measured by assessing the overnight dynamics in sleep spindle frequency. Phase of the minimal sleep spindle frequency is a putative biomarker of chronotype.

scholarly journals Evidence That Homeostatic Sleep Regulation Depends on Ambient Lighting Conditions during Wakefulness

2019 ◽  
Vol 1 (4) ◽  
pp. 517-531 ◽  
Author(s):  
Christian Cajochen ◽  
Carolin Reichert ◽  
Micheline Maire ◽  
Luc J. M. Schlangen ◽  
Christina Schmidt ◽  
...  
Keyword(s):  
Slow Wave ◽  
White Light ◽  
Slow Wave Sleep ◽  
Age Groups ◽  
Sleep Regulation ◽  
Older Volunteers ◽  
Lighting Conditions ◽  
Ambient Lighting ◽  
Sleep Homeostasis ◽  
Subjective Sleepiness

We examined whether ambient lighting conditions during extended wakefulness modulate the homeostatic response to sleep loss as indexed by. slow wave sleep (SWS) and electroencephalographic (EEG) slow-wave activity (SWA) in healthy young and older volunteers. Thirty-eight young and older participants underwent 40 hours of extended wakefulness [i.e., sleep deprivation (SD)] once under dim light (DL: 8 lux, 2800 K), and once under either white light (WL: 250 lux, 2800 K) or blue-enriched white light (BL: 250 lux, 9000 K) exposure. Subjective sleepiness was assessed hourly and polysomnography was quantified during the baseline night prior to the 40-h SD and during the subsequent recovery night. Both the young and older participants responded with a higher homeostatic sleep response to 40-h SD after WL and BL than after DL. This was indexed by a significantly faster intra-night accumulation of SWS and a significantly higher response in relative EEG SWA during the recovery night after WL and BL than after DL for both age groups. No significant differences were observed between the WL and BL condition for these two particular SWS and SWA measures. Subjective sleepiness ratings during the 40-h SD were significantly reduced under both WL and BL compared to DL, but were not significantly associated with markers of sleep homeostasis in both age groups. Our data indicate that not only the duration of prior wakefulness, but also the experienced illuminance during wakefulness affects homeostatic sleep regulation in humans. Thus, working extended hours under low illuminance may negatively impact subsequent sleep intensity in humans.

scholarly journals Evidence that Homeostatic Sleep Regulation Depends on Ambient Illuminance Levels

2019 ◽  
Author(s):  
Christian Cajochen ◽  
Carolin Reichert ◽  
Micheline Maire ◽  
Luc J M Schlangen ◽  
Christina Schmidt ◽  
...  
Keyword(s):  
Slow Wave ◽  
White Light ◽  
Slow Wave Sleep ◽  
Age Groups ◽  
Wave Activity ◽  
Sleep Regulation ◽  
Older Volunteers ◽  
Sleep Homeostasis ◽  
Subjective Sleepiness ◽  
Dim Light

We examined whether the ambient illuminance during extended wakefulness modulates the homeostatic increase in human deep sleep [i.e. slow wave sleep (SWS) and electroencephalographic (EEG) slow-wave activity (SWA)] in healthy young and older volunteers. Thirty-eight young and older participants underwent 40 hours of extended wakefulness [i.e. sleep deprivation (SD)] once under dim light (DL: 8 lux, 2800K), and once under either white light (WL: 250 lux, 2800K) or blue-enriched white light (BL: 250 lux, 9000K) exposure. Subjective sleepiness was assessed hourly and polysomnography was quantified during the baseline night prior to the 40-h SD and during the subsequent recovery night. Both the young and older participants responded with a higher homeostatic sleep response to 40-h SD after WL and BL than after DL. This was indexed by a significantly faster intra-night accumulation of SWS and a significantly higher response in relative EEG SWA during the recovery night after WL and BL than after DL for both age groups. No significant differences were observed between the WL and BL condition for these two particular SWS and SWA measures. Subjective sleepiness ratings during the 40-h SD were significantly reduced under both WL and BL compared to DL, but were not significantly associated with markers of sleep homeostasis in both age groups. Our data indicate that not only the duration of prior wakefulness, but also the experienced illuminance during wakefulness affects homeostatic sleep regulation in humans. Thus, working extended hours under low illuminance may negatively impact subsequent sleep intensity in humans.

Age-related reference values for urinary organic acids in a healthy Turkish pediatric population

1994 ◽  
Vol 40 (6) ◽  
pp. 862-868 ◽  
Author(s):  
F Guneral ◽  
C Bachmann
Keyword(s):  
Organic Acids ◽  
Reference Data ◽  
Pediatric Population ◽  
Age Groups ◽  
Caloric Intake ◽  
Urinary Organic Acids ◽  
Age Related ◽  
Data Correlations ◽  
The Individual ◽  
Urine Specimens

Abstract Organic acid concentrations were quantified by gas chromatography and the individual acids identified by mass spectrometry in urine specimens from a healthy Turkish pediatric population of ages 2 days to 16 years, subdivided into five age groups. We quantified 69 organic acids (32 major and 37 minor components) and report here the median values and percentiles for each compound, adjusted for creatinine content, for the five groups. Concentrations of most of the organic acids tend to decrease with age but display substantial differences between age groups. This emphasizes the importance of comparing patients' data with age-matched reference data. Correlations between the excretion of organic acids and protein or caloric intake were significant for several compounds.

scholarly journals The adolescent pattern of sleep spindle development revealed by HD-EEG polisomnography

2021 ◽  
Author(s):  
Gabor Bocskai ◽  
Adrian Potari ◽  
Ferenc Gombos ◽  
Robert Bodizs ◽  
Ilona Kovacs
Keyword(s):  
Adolescent Development ◽  
Age Groups ◽  
Sleep Spindles ◽  
Age Group ◽  
Sleep Spindle ◽  
Frequency Range ◽  
Equal Distribution ◽  
Functional Relevance ◽  
Spindle Development ◽  
Developmental Analysis

Sleep spindles are developmentally relevant cortical oscillatory patterns; however, they have mostly been studied by considering the entire spindle frequency range (11 to 15 Hz) without a distinction between the functionally and topographically different slow and fast spindles, using relatively few electrodes and analysing wide age-ranges. Here, we employ HD-EEG polysomnography in three age-groups between 12 to 20 years of age, with an equal distribution between the two genders, and analyse the adolescent developmental pattern of the four major parameters of slow and fast sleep spindles. Most of our findings corroborate those very few previous studies that also make a distinction between slow and fast spindles in their developmental analysis. We find spindle frequency increasing with age, although spindle density change is not obvious in our study. We confirm the declining tendencies for amplitude and duration, although within narrower, more specific age-windows than previously. Spindle frequency seems to be higher in females in the oldest age-group. Based on the pattern of our findings, we suggest that HD-EEG, specifically targeting slow and fast spindle ranges and relatively narrow age-ranges would advance the understanding of both adolescent development and the functional relevance of sleep spindles in general.

029 Median preoptic dual control over sleep regulation

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A13-A14
Author(s):  
Natalia Machado ◽  
William Todd ◽  
Clifford Saper
Keyword(s):  
Nrem Sleep ◽  
Underlying Mechanism ◽  
Brain Regions ◽  
Sleep Cycle ◽  
Sleep Regulation ◽  
Sleep Behavior ◽  
Sleep Homeostasis ◽  
Psychological Stressor ◽  
Sleep Control

Abstract Introduction Previous studies suggest that the median preoptic nucleus (MnPO) plays an important role in regulating the wake-sleep cycle and in particular homeostatic sleep drive. However, the precise cellular phenotypes, targets and central mechanisms by which the MnPO neurons regulate the wake-sleep cycle remain unknown. Both glutamatergic (Vglut2+) and GABAergic (Vgat+) MnPO neurons innervate brain regions implicated in sleep promotion and maintenance, suggesting that both cell types may participate on sleep control. Methods In this study, we used two genetically-targeted approaches associated with electroencephalographic (EEG) and electromyographic (EMG) recordings in Vgat-IRES-cre and Vglut2-IRES-cre mice to investigate the role of the MnPOVgat and MnPOVglut2 neurons in modulating wake-sleep behavior. Results First, using a chemogenetic approach, we found that activation of MnPOVgat neurons reduced the latency for the first NREM sleep episode, produced an increase in NREM sleep and reduced wakefulness. Then, to test the role of MnPOVgat and MnPOVglut2 neurons in regulating sleep homeostasis, we recorded EEG and EMG responses in mice that had the Vgat+ or Vglut2+ neurons deleted from the MnPO. After deletion of MnPOVgat neurons, mice showed a reduction of NREM sleep and an increase in wakefulness during the light phase. Deletion of MnPOVgat neurons also reduced sleep recovery after 4 hours of sleep deprivation (SD). On the other hand, deletion of the MnPOVglut2 neurons did not change the wake-sleep cycle during the 24h baseline condition, but prevented the sleep recovery immediately after SD. To understand the underlying mechanism in preventing sleep recovery in both MnPOVglut2- and MnPOVgat-deleted mice groups, we exposed these animals to a psychological stress protocol. In response to a psychological stressor, mice with deletion of glutamatergic, but not GABAergic MnPO neurons, had an exacerbation of the stress-induced insomnia. Conclusion Our results suggest that both neuron populations differentially participate in wake-sleep control, with MnPOVgat neurons being critically involved in sleep homeostasis, and MnPOVglut2 neurons promoting sleep during allostatic (stressful) challenges. Support (if any) NIH Grants NS085477, NS072337, HL095491 and Sleep Research Society Foundation (Award 026-JP-20).

Immigrant Youth in Germany

2013 ◽  
Vol 18 (3) ◽  
pp. 158-168 ◽  
Author(s):  
Emily Frankenberg ◽  
Katharina Kupper ◽  
Ruth Wagner ◽  
Stephan Bongard
Keyword(s):  
School System ◽  
Large Scale ◽  
Age Groups ◽  
Well Being ◽  
Ethnic Discrimination ◽  
Emotional And Behavioral Problems ◽  
Sociocultural Adaptation ◽  
Age Related ◽  
German School ◽  
Transcultural Adaptation

This paper reviews research on young migrants in Germany. Particular attention is given to the question of how Germany’s history of migration, immigration policies, and public attitude toward migrants influence the transcultural adaptation of children and adolescents from different ethnic backgrounds. We combine past research with the results of new empirical studies in order to shed light on migrants’ psychological and sociocultural adaptation. Studies comparing young migrants and their German peers in terms of psychological well-being, life satisfaction, and mental health outcome suggest higher rates of emotional and behavioral problems among migrants of most age groups. With regard to adolescent populations between the ages of 14 and 17 years, however, the existence of differences between migrants and natives appears to be less clear. Research has also yielded inconsistent findings regarding the time trajectory of transcultural adaptation among adolescents. The coincidence of acculturation and age-related change is discussed as a possible source of these inconsistencies. Further, we provide an overview of risk and protective factors such as conflicting role expectations and ethnic discrimination, which may cause heightened vulnerability to adverse adaptation outcomes in some groups. Large-scale studies have repeatedly shown migrants of all age groups to be less successful within the German school system, indicating poor sociocultural adaptation. Possible explanations, such as the idiosyncrasies of the German school system, are presented. Our own studies contribute to the understanding of young migrants’ adaptation process by showing that it is their orientation to German culture, rather than the acculturation strategy of integration, that leads to the most positive psychological and sociocultural outcomes. The paper concludes by discussing implications for future cross-cultural research on young migrants and by suggesting recommendations for multicultural policies.

The influence of osteopathic correction on the rate of various rhythms of the body

2019 ◽  
pp. 64-71 ◽  
Author(s):  
A. E. Chernikova ◽  
Yu. P. Potekhina
Keyword(s):  
Heart Rate ◽  
Respiratory Rate ◽  
Age Groups ◽  
Biomechanical Properties ◽  
Dispersion Analysis ◽  
The Body ◽  
Body Tissues ◽  
Age Related ◽  
Significant Difference ◽  
Before And After

Introduction. An osteopathic examination determines the rate, the amplitude and the strength of the main rhythms (cardiac, respiratory and cranial). However, there are relatively few studies in the available literature dedicated to the influence of osteopathic correction (OC) on the characteristics of these rhythms.Goal of research — to study the influence of OC on the rate characteristics of various rhythms of the human body.Materials and methods. 88 adult osteopathic patients aged from 18 to 81 years were examined, among them 30 men and 58 women. All patients received general osteopathic examination. The rate of the cranial rhythm (RCR), respiratory rate (RR) heart rate (HR), the mobility of the nervous processes (MNP) and the connective tissue mobility (CTM) were assessed before and after the OC session.Results. Since age varied greatly in the examined group, a correlation analysis of age-related changes of the assessed rhythms was carried out. Only the CTM correlated with age (r=–0,28; p<0,05) in a statistically significant way. The rank dispersion analysis of Kruskal–Wallis also showed statistically significant difference in this indicator in different age groups (p=0,043). With the increase of years, the CTM decreases gradually. After the OC, the CTM, increased in a statistically significant way (p<0,0001). The RCR varied from 5 to 12 cycles/min in the examined group, which corresponded to the norm. After the OC, the RCR has increased in a statistically significant way (p<0,0001), the MNP has also increased (p<0,0001). The initial heart rate in the subjects varied from 56 to 94 beats/min, and in 15 % it exceeded the norm. After the OC the heart rate corresponded to the norm in all patients. The heart rate and the respiratory rate significantly decreased after the OC (р<0,0001).Conclusion. The described biorhythm changes after the OC session may be indicative of the improvement of the nervous regulation, of the normalization of the autonomic balance, of the improvement of the biomechanical properties of body tissues and of the increase of their mobility. The assessed parameters can be measured quickly without any additional equipment and can be used in order to study the results of the OC.

Age related volume of cadaver-prostates in Bangladesh

1970 ◽  
Vol 4 (2) ◽  
pp. 74-77
Author(s):  
Rukshana Ahmed ◽  
Shamim Ara
Keyword(s):  
Prostate Gland ◽  
Age Groups ◽  
Clinical Settings ◽  
Cross Sectional ◽  
Medical College ◽  
Age Related ◽  
Group A ◽  
Key Words Prostate ◽  
The Mean ◽  
Group B

Pathological changes in the prostate gland occur commonly with advancing age including inflammation, atrophy, hyperplasia and carcinoma and a change in volume is also evident. Estimation of volume of prostate may be useful in a variety of clinical settings. A cross-sectional descriptive study was designed to see the changes in volume of the prostate with advancing age and done in the Department of Anatomy, Dhaka Medical College, Dhaka from August 2006 to June 2007. The study was performed on 70 post-mortem human prostates collected from the unclaimed dead bodies that were under examination in the Department of Forensic Medicine, Dhaka Medical College, Dhaka. The samples were divided into three age groups; group A (10-20 years), group B (21-40 years) and group C (41-70 years). Volume of the sample was measured by using the ellipsoid formula. The mean ± SD volume of prostate was 7.68 ± 3.64 cm3 in group A, 10.61 ± 3.99 cm3 in group B and 15.40 ± 6.31 cm3 in group C. Mean difference in volume between group A and group C, group B and group C were statistically significant (p<0.001). Statistically significant positive correlation was found between age and volume of prostate (r = + 0.579, p < 0.001). Key Words: Prostate; volume; Bangladeshi. DOI: 10.3329/imcj.v4i2.6501Ibrahim Med. Coll. J. 2010; 4(2): 74-77

Age development of cortical rhythmics in the EEG depending on the formation of the child’s personal psychical characteristics

2019 ◽  
Vol 1 (8) ◽  
pp. 42-50
Author(s):  
A. V. Budkevich ◽  
L. B. Ivanov ◽  
G. R. Novikova ◽  
G. M. Dzhanumova
Keyword(s):  
Alpha Rhythm ◽  
Age Groups ◽  
Healthy Children ◽  
Brain Organization ◽  
Age Related ◽  
Mathematical Processing ◽  
Functional Brain Organization ◽  
Child's Brain ◽  
Attention Function ◽  
Apparently Healthy

According to the authors, rationing the age-related EEG parameters in children should be based on personal psychical characteristics. A comparative analysis of personal psychical characteristics and electroencephalographic data was carried out in 300 apparently healthy children aged 3-15 years. According to this principle, two subgroups of conditionally healthy children in each age group were singled out: 1) with an immature attention function and 2) with an increased anxious background that do not reach the pathological level. Registration and analysis of EEG was performed by the Neurokariograf computer complex (MBN, Moscow) using mathematical processing methods.The EEG interpretation was based on the principle of assessing the functional state of a child's brain using a three-component model according to: 1) wakefulness level and its dissociation, 2) severity of signs of the EEG neurotic pattern, 3) directionality of formation of traits of the system-functional brain organization (severity of signs functional hypofrontality).lt was found the presence of EEG signs was indicative of a lower level of wakefulness in children with an immature function of attention in all age groups, compared with the indicators of the average population of group and children with an increased background of anxiety. Children with an increased background of anxiety have a tendency to prevalence and excessive spatial synchronization of the alpha rhythm. ln healthy children, the fact of a decrease in wakefulness and the presence of signs of anxiety in the clinic and in EEG patterns indicates individual personalities and should not be considered as pathology.

Information Practices of Baby Boomers as Caregivers

2013 ◽  
Author(s):  
Khuan Seow ◽  
Nadia Caidi
Keyword(s):  
Social Policy ◽  
Baby Boomers ◽  
Information Needs ◽  
Family Members ◽  
Age Groups ◽  
Maladie D’Alzheimer ◽  
Policy Makers ◽  
Age Related ◽  
The Family ◽  
Growing Age

Canada has an aging population with the fastest growing age groups (80 and 45-64 years old) vulnerable to age-related diseases such as Alzheimer’s disease. Caregiving responsibilities often fall to the family members of the afflicted without much attention and consideration being placed on the information needs of these caregivers. We call for a better understanding of these caregivers' information needs and uses by social policy makers as well as information providers.La population du Canada a tendance à vieillir considérablement, avec la hausse la plus rapide dans les groupes d’âge (80 et 45 à 64 ans). Les personnes âges sont très vulnérables à toute sorte de maladies, telles que la maladie d’Alzheimer. La responsabilité revient souvent aux membres de la famille qui doivent prendre soin des personnes atteintes de cette maladie. Or, nous ne connaissons que peu de chose sur les besoins en information des personnes qui prennent soin de ces malades de l’Alzheimer : qui sont-ils ? Quelles sont leurs sources... 

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