Effects of heat exposure on the thermoregulatory responses of young children.

The purpose of this study was to determine whether young children's thermoregulation during heat exposure varies with age and body size. A total of 34 young children (aged 6 months-8 years)-18 boys and 16 girls-participated in the study. They were divided into five groups according to age (<1 year, 1 year, 2-3 years, 4-5 years, and 8 years).

Can a short nap and bright light function as implicit learning and visual search enhancers?

The present study examined effects of a short nap (20 min) and/or bright light (2000 lux) on visual search and implicit learning in a contextual cueing task. Fifteen participants performed a contextual cueing task twice a day (1200-1330 h and 1430-1600 h) and scored subjective sleepiness before and after a short afternoon nap or a break period. Participants served a total of four experimental conditions (control, short nap, bright light and short nap with bright light).

The relationship between flow, sleepiness and cognitive performance: the effects of short afternoon nap and bright light exposure.

"Flow" is a positive emotional state which typically occurs when a person perceives a balance between the challenges associated with a situation and his or her capabilities to accomplish these demands. While flow often occurs along with positive feelings and high introspective performance, only a few studies have investigated how it is associated with cognitive performance (i.e.

Effects of season on sleep and skin temperature in the elderly.

The effects of season on sleep and skin temperature (Tsk) in 19 healthy, elderly volunteers were investigated. Measurements were obtained in summer, winter, and fall, and activity levels were monitored using a wrist actigraph system for five consecutive days. The temperature and humidity of the bedrooms of the subjects' homes were measured continuously for five days.

Effects of low ambient temperature on heart rate variability during sleep in humans.

The effects of cold exposure on heart rate variability (HRV) during sleep were examined. Eight male subjects slept under three different conditions: 3 degrees C, 50-80% relative humidity (RH) [3]; 10 degrees C, 50% RH [10]; and 17 degrees C 50% RH [17]. No significant differences were observed in HRV during rapid eye movement sleep (REM) and wakefulness.

Comparison of thermal responses between young children (1- to 3-year-old) and mothers during cold exposure.

To investigate thermal responses of children during cold exposure, children and their mothers were exposed to identical environmental conditions in climatic chambers. Subjects comprised 14 mothers (age, 29-40 years) and 15 children (age, 15 months-3 years; 9 boys, 6 girls). Each mother and child wore a t-shirt and short pants over underwear.

Effects of airflow on body temperatures and sleep stages in a warm humid climate.

Airflow is an effective way to increase heat loss-an ongoing process during sleep and wakefulness in daily life. However, it is unclear whether airflow stimulates cutaneous sensation and disturbs sleep or reduces the heat load and facilitates sleep. In this study, 17 male subjects wearing short pyjamas slept on a bed with a cotton blanket under two of the following conditions: (1) air temperature (Ta) 26 degrees C, relative humidity (RH) 50%, and air velocity (V) 0.

Effects of an electric blanket on sleep stages and body temperature in young men.

The aim of this study was to investigate any effects of electric blanket on sleep stages and body temperature. Nine male subjects slept under two conditions: using the electric blanket (HB); and not using the electric blanket (C). The ambient condition was controlled at 3 degrees C relative humidity 50-80%.

Effects of partial humid heat exposure during different segments of sleep on human sleep stages and body temperature.

The effects of partial humid heat exposure applied at different segments of sleep on sleep stages and body temperature were examined. In the first experiment, eight male subjects slept under 26 degrees C 50% (26) and 26 degrees C for the first 3 h and 45 min followed by a 30-min transition to the conditions of 32 degrees C 80%, which was maintained for the final 3 h and 45 min (26-32). Wakefulness increased significantly over the last 4 h under 26-32 compared to 26.

Effects of humid heat exposure in later sleep segments on sleep stages and body temperature in humans.

This study sought to investigate the effects of humid heat exposure in later sleep segments on sleep stages and body temperature in humans. The subjects were eight healthy males, from whom informed consent had been obtained. The experiments were carried out under three different sets of conditions: a control climate [air temperature (Ta)=26 degrees C, relative humidity (RH)=50%] (C); a humid heat climate (Ta=32 degrees C, RH=80%) (H); and a humid heat exposure in later sleep segments (C for the first 3 h 45 min, followed by a 30-min transition to H, which was then maintained for the last 3 h 45 min) (C-H).

Effects of head cooling on human sleep stages and body temperature.

The purpose of this study was to confirm the effect of head cooling on human sleep stages and body temperature. Nine healthy male volunteers with a mean age of 25 +/- 3.77 years served as subjects.