Browsing by Subject "Chronobiology"
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- PublicationEmbargoActivity-rest circadian pattern and academic achievement, executive function, and intelligence in children with obesity(Wiley, 2020-10-23) Migueles, Jairo H.; Martínez Nicolás, Antonio; Cadenas Sánchez, Cristina; Esteban Cornejo, Irene; Muntaner Mas, Adrià; Mora González, José; Rodríguez Ayllón, María; Madrid, Juan Antonio; Rol de Lama, María de los Ángeles; Hillman, Charles H.; Catena, Andrés; Ortega, Francisco B.; FisiologíaThis study aimed to analyze the associations of activity-rest pattern indicators with academic achievement, executive function, and intelligence and to explore whether these associations are mediated by the total gray matter volume among children with overweight/obesity. Ninety-five children (10 ± 1 year, 37 girls) with overweight/obesity (based on the World Obesity Federation body mass index cutoff points) were included in this cross-sectional study. Hip- and wrist-worn ActiGraph GT3X + accelerometers were used to assess the activity-rest pattern. Interdaily stability (IS), intradaily variability (IV), the mean value of the lowest 5 hours (L5), and the mean value of the maximum 10 hours (M10) of activity and their respective timing (TL5, TM10) were used as indicators of the activity-rest pattern throughout the day. Chronotype and social jetlag were used as indicators of circadian preference. Academic achievement, executive function, and intelligence were assessed with standardized tests. Gray matter volume was acquired by magnetic resonance imaging (MRI). IS was positively associated with executive function (β = 0.244, P = .014). IV was negatively associated with mathematics and academic applications (β: −0.211 to −0.238, P’s ≤ .026). Later TM10 in the day was related to lower writing, academic skills, and intelligence (β: −0.229 to −0.271, P’s ≤ .025). None of the associations found were mediated by gray matter volume. A non-fragmented and stable activity-rest pattern and earlier physical activity in the day were associated with better academic achievement, executive function, and intelligence in children with overweight/obesity. Further studies are required to corroborate or contrast our findings.
- PublicationOpen AccessCorrelated color temperature and light intensity: complementary features in non-visual light field(Public Library of Science (PLoS), 2021-07-12) Arguelles Prieto, Raquel; Madrid, Juan Antonio; Rol de Lama, María de los Ángeles; Bonmatí Carrión, María de los Ángeles; FisiologíaAn appropriate exposure to the light-dark cycle, with high irradiances during the day and darkness during the night is essential to keep our physiology on time. However, considering the increasing exposure to artificial light at night and its potential harmful effects on health (i.e. chronodisruption and associated health conditions), it is essential to understand the non-visual effects of light in humans. Melatonin suppression is considered the gold standard for nocturnal light effects, and the activation of intrinsically photosensitive retinal ganglion cells (ipRGCs) through the assessment of pupillary light reflex (PLR) has been recently gaining attention. Also, some theoretical models for melatonin suppression and retinal photoreceptors activation have been proposed. Our aim in this study was to determine the influence of correlated color temperature (CCT) on melatonin suppression and PLR, considering two commercial light sources, as well as to explore the possible correlation between both processes. Also, the contribution of irradiance (associated to CCT) was explored through mathematical modelling on a wider range of light sources. For that, melatonin suppression and PLR were experimentally assessed on 16 healthy and young volunteers under two light conditions (warmer, CCT 3000 K; and cooler, CCT 5700 K, at ~5·1018 photons/cm2/sec). Our experimental results yielded greater post-stimulus constriction under the cooler (5700 K, 13.3 ± 1.9%) than under the warmer light (3000 K, 8.7 ± 1.2%) (p < 0.01), although no significant differences were found between both conditions in terms of melatonin suppression. Interestingly, we failed to demonstrate correlation between PLR and melatonin suppression. Although methodological limitations cannot be discarded, this could be due to the existence of different subpopulations of Type 1 ipRGCs differentially contributing to PLR and melatonin suppression, which opens the way for further research on ipRGCs projection in humans. The application of theoretical modelling suggested that CCT should not be considered separately from irradiance when designing nocturnal/diurnal illumination systems. Further experimental studies on wider ranges of CCTs and light intensities are needed to confirm these conclusions.
- PublicationEmbargoIntegral Analysis of Circadian Rhythms(Yolanda Larriba, 2023-08-10) Vicente-Martinez, J; Almaida Pagán, Pedro Francisco; Martinez-Nicolas, A; Madrid, Juan A; Rol, M A; Bonmatí Carrión, María de los Ángeles; Fisiología; Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable, Instituto de Salud Carlos III, Madrid, SpainOur biological processes do not present a static and steady picture. Instead, most of these processes oscillate throughout the 24-h day. The system that controls this circadian rhythmicity is composed of a central pacemaker and peripheral oscillators that rely on inputs and produce outputs that can be measured through appropriate techniques. The correct measurement and analysis of the func-tioning of each part of the circadian system are becoming essential in many fields of biomedicine. In this chapter, we will cover the entire process, from the acquisition of circadian data to their analyses through parametric and non-parametric methods, including the dynamic modeling of different circadian processes.
- PublicationOpen AccessRelationship between human pupillary light reflex and circadian system status(Public Library of Science, 2016-09-16) Hild, Konstanze; Isherwood, Cheryl; Sweeney, Stephen J.; Revell, Victoria L.; Skene, Debra J.; Rol, Maria Ángeles; Madrid, Juan Antonio; Bonmatí Carrión, María de los Ángeles; Anatomía Humana y PsicobiologíaIntrinsically photosensitive retinal ganglion cells (ipRGCs), whose photopigment melanopsin has a peak of sensitivity in the short wavelength range of the spectrum, constitute a common light input pathway to the olivary pretectal nucleus (OPN), the pupillary light reflex (PLR) regulatory centre, and to the suprachiasmatic nuclei (SCN), the major pacemaker of the circadian system. Thus, evaluating PLR under short wavelength light (λmax 500 nm) and creating an integrated PLR parameter, as a possible tool to indirectly assess the status of the circadian system, becomes of interest. Nine monochromatic, photon-matched light stimuli (300 s), in 10 nm increments from λmax 420 to 500 nm were administered to 15 healthy young participants (8 females), analyzing: i) the PLR; ii) wrist temperature (WT) and motor activity rhythms (WA), iii) light exposure (L) pattern and iv) diurnal preference (HorneÖstberg), sleep quality (Pittsburgh) and daytime sleepiness (Epworth). Linear correlations between the different PLR parameters and circadian status index obtained from WT, WA and L recordings and scores from questionnaires were calculated. In summary, we found markers of robust circadian rhythms, namely high stability, reduced fragmentation, high amplitude, phase advance and low internal desynchronization, were correlated with a reduced PLR to 460–490 nm wavelengths. Integrated circadian (CSI) and PLR (cp-PLR) parameters are proposed, that also showed an inverse correlation. These results demonstrate, for the first time, the existence of a close relationship between the circadian system robustness and the pupillary reflex response, two non-visual functions primarily under melanopsin-ipRGC input.