Correlated colour temperature of morning light influences alertness and body temperature.

Physiol Behav

Department of Human Biology & Movement Sciences, NUTRIM, Maastricht University, Maastricht, The Netherlands.

Published: March 2018

Though several studies have reported human alertness to be affected by the intensity and spectral composition of ambient light, the mechanism behind this effect is still largely unclear, especially for daytime exposure. Alerting effects of nocturnal light exposure are correlated with melatonin suppression, but melatonin levels are generally low during the day. The aim of this study was to explore the alerting effect of light in the morning for different correlated colour temperature (CCT) values, as well as its interaction with ambient temperature. Body temperature and perceived comfort were included in the study as possible mediating factors. In a randomized crossover design, 16 healthy females participated in two sessions, once under 2700K and once under 6500K light (both 55lx). Each session consisted of a baseline, a cool, a neutral and a warm thermal environment. Alertness as measured in a reaction time task was lower for the 6500K exposure, while subjective sleepiness was not affected by CCT. Also, core body temperature was higher under 6500K. Skin temperature parameters and perceived comfort were positively correlated with subjective sleepiness. Reaction time correlated with heat loss, but this association did not explain why the reaction time was improved for 2700K.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.physbeh.2017.12.004DOI Listing

Publication Analysis

Top Keywords

body temperature
12
reaction time
12
correlated colour
8
colour temperature
8
perceived comfort
8
subjective sleepiness
8
temperature
7
correlated
5
light
5
temperature morning
4

Similar Publications

The ground states of two-species condensates with spin-1 atoms have been studied analytically and numerically. All the results from the analytical approach are checked by the latter. The [Formula: see text] channel has been neglected, where λ is the coupled spin of two different atoms.

View Article and Find Full Text PDF

3D-printed ultra-sensitive strain sensors using biogels prepared from fish gelatin and gellan gum.

Carbohydr Polym

March 2025

Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition (Ministry of Education), Fujian Agriculture and Forestry University, Fuzhou 350002, China; College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; China-Ireland International Cooperation Centre for Food Material Science and Structural Design, Fuzhou 350002, China. Electronic address:

The long-term sustainable development of flexible electronic devices is limited by a reliance on synthetic polymers that pose dangers for humans and potentially severe ecological problems, as well as a reliance on conventional processing methods. This work aims to exploit 3D printing to develop natural biogels composed of fish gelatin and high acyl gellan gum for use as flexible sensors. The electrical conductivity and mechanical strength were remarkably enhanced through the environmentally friendly enzyme (transglutaminase) cross-linking and non-toxic ethanol modification treatment, which allows the development of 3D printed sensors for temperature, strain, and stress sensors.

View Article and Find Full Text PDF

Identification of hypothermia-inducing neurons in the preoptic area and activation of them by isoflurane anesthesia and central injection of adenosine.

J Physiol Sci

January 2025

Department of Physiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Sakuragaoka 8-35-1, 890-8544, Kagoshima, Japan. Electronic address:

Hibernation and torpor are not passive responses caused by external temperature drops and fasting but are active brain functions that lower body temperature. A population of neurons in the preoptic area was recently identified as such active torpor-regulating neurons. We hypothesized that the other hypothermia-inducing maneuvers would also activate these neurons.

View Article and Find Full Text PDF

Nail growth arrest under low body temperature during hibernation.

J Physiol Sci

January 2025

Hibernation Metabolism, Physiology and Development Group, Institute of Low Temperature Science, Hokkaido University, Sapporo, Hokkaido, Japan; Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan; Inamori Research Institute for Science Fellowship (InaRIS), Kyoto, Japan. Electronic address:

Growth and differentiation are reduced or stopped during hibernation, an energy conserving strategy in harsh seasons by lowered metabolism and body temperature. However, few studies evaluated this in a same individual using a non-invasive method. In this study, we applied a non-invasive tracking method of the nail growth throughout the hibernation period in the same hibernating animals, the Syrian hamster (Mesocricetus auratus).

View Article and Find Full Text PDF

Evaluation of newly developed wearable ear canal thermometer, mimicking the application to activities on sports and labor fields.

J Physiol Sci

January 2025

Sustainable Energy and Environmental Society Open Innovation Research Organization, Waseda University, Nishiwaseda 1-6-1, Shinjuku-ku, 169-8050, Tokyo, Japan; Body Temperature and Fluid Laboratory, Graduate School of Human Sciences, Faculty of Human Sciences, Waseda University, Mikajima 2-579-15, 359-1192, Tokorozawa, Saitama, Japan. Electronic address:

We evaluated the reliability of a newly developed wearable ear canal thermometer based on three different experiments, in which ear canal and rectal temperature (T and T, respectively) were simultaneously monitored. In Experiment 1, participants sat at 28°C and 50% relative humidity (RH), during which fanning or 41°C lower legs water immersion was conducted. In Experiment 2, participants conducted a 70-min treadmill exercise (4 km/h, 0.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!