François Testu

Role of school schedule, age, and parental socioeconomic status on sleep duration and sleepiness of Parisian children.

The aim of the study was to assess the duration and quality of sleep of prepubertal (Tanner Scale level 1) physically and mentally healthy children as a function of school schedule (4 versus 4.5 days per week), age and grade (median age of 9.5 years for 4th grade versus median age of 10.5 years for 5th grade), school district (wealthy versus nonwealthy) in Paris, France, and parental socioeconomic status (high, medium, or low). We studied 51 girl and 44 boy volunteer pupils with written parental consent. The study lasted 2 weeks during the month of March. During the first study week, the children attended school 4.5 days, and during the second week, they attended school only 4 days without difference in the length of the school day. A sleep log was used to ascertain time of lights off for sleep and lights on at awakening, nighttime sleep duration, and self-rated sleep quality. A visual analog scale (VAS) was also used by pupils to self-rate the level of perceived sleepiness at four specific times of the school day. Conventional statistical methods (e.g., t and χ2tests) were used to examine differences in mean values. Sleep duration, self-rated sleepiness, and subjective sleep quality were comparable (P >. 05) by gender, school schedule, school district, and parental socioeconomic status. Overall, the sleep of this sample of Parisian children around 10 years of age was rather stable in its duration and timing, suggesting flexibility to adjust to the different school schedules. (Chronobiology International, 18 (6), 1005–1017, 2001)

Age‐Related Differences in Daily Attention Patterns in Preschool, Kindergarten, First‐Grade, and Fifth‐Grade Pupils

The purpose of this study was to examine age‐related differences in the daily attention patterns of preschool, kindergarten, first‐grade, and fifth‐grade pupils by means of a cross‐sectional sample of 4–11‐year‐old French students. The importance of this study comes from the need to understand attention and apply the information it provides in educational settings. The first study conducted in a school setting with three age groups (4–5‐, 6–7‐, and 10–11‐year‐olds) demonstrated a rapid rhythmicity (60 minute period) for preschoolers (4–5 years old), with higher performance at the beginning of a teaching session. This pattern evolved until the fifth grade (10–11‐year‐olds), after which the temporal variation in attention was comparable to that of working adults, with fluctuations occurring on a half‐day basis. The childrens scores on crossing‐out tests rose during the morning, declined in the early afternoon, and then rose again later during the afternoon. The second study enhanced our understanding of the change of the rhythm in attention of 4–7‐year‐old pupils. The rapid daily rhythmicity, linked to a session effect, seems to gradually disappear as children move from preschool 2 to kindergarten (4–5‐ to 5–6‐year‐olds) and then on to first grade (6–7‐year‐olds), where the daily attention patterns are closer to the standard pattern found by chronopsychology studies. The evolving patterns obtained from group means were confirmed by analysis of individual patterns. Exploratory statistical analysis of the data provided greater detail on the observed interindividual patterns, indicating that within each school grade, the attention patterns of some children are similar to the standard pattern while the attention patterns of others are more atypical. Deviations were mainly found in the 5–6‐year‐old age range (kindergarteners). The greatest ‘mixture’ of patterns was observed in the kindergartners (5–6‐year‐olds). Age plays a role not only in modifying daily changes but also in the distribution of interindividual differences in daily fluctuations, which occur most when children are of kindergarten age (5–6 years of age).

Time-of-day and day-of-week effects on mnemonic performance.

The present study attempts to determine whether diurnal variations in memory performance like the ones observed by Folkard et al. (1977) are independent of the testing day (Monday or Thursday) and the type of material (story or word list). In the experiment, 103 pupils aged 10 and 11 had to listen to a story and learn a list of 14 nouns at 09:00 or 15:00 on Monday or Thursday. Immediately after presentation of the information and then again 1 week later the pupils had to answer questions about the story and recall the list of nouns. The results showed that the type of task had no effect on memory performance, but immediate and delayed recall scores were dependent on both the time and the day the information was presented. Moreover, memory performance was also affected by the time at which the delayed recall test took place. On Monday and especially on Thursday, better performance was obtained at 09:00. This data only partially confirms the findings of Folkard et al.

Diurnal variation in mental activities of French pupils and influence of test protocol.

The aim of the study was to determine the influence of the test protocol (individual vs. group) on the diurnal variations in mental activity of 18 11-year-old pupils. Number cancellation, a spatial orientation test, and mathematical problems were tested four times on three successive Fridays at 08:45, 11:15, 13:45 and 16:45 h. On the first and third Fridays the tests were performed on the group of subjects, whereas individual subjects were tested on the second Friday. Results indicated a possible influence of the test protocol (individual vs. group) on intellectual rhythmicity. Only in the group protocol did we find the psychological profile which is normally observed, namely, a performance increase during the morning, a postlunch fall, and then an increase in the afternoon. We suggest the existence of some group effect in these performance tests.

Effects of Alcohol on Psycho-Technical Tests and Social Communication in a Festive Situation: A Chronopsychological Approach

The aim of this study was to determine the effect of consuming alcoholic vs. nonalcoholic beverages on performance of psycho-technical tasks (attentional and general nonverbal intelligence tasks) and social behavior at different times of day. Both alcoholic and nonalcoholic consumption took place in a largely festive situation. The experiment was conducted on 184 degree-level and postgraduate students (94 female and 90 male) divided into eight independent groups for study at different times: 8:00 to 11:00, 11:00 to 14:00, 14:00 to 17:00, 17:00 to 20:00 h. The main result obtained, by analysis of variance (ANOVA), showed that time of day had no effect on the performance of psycho-technical tasks nor on social communication, except for the retest situation in the attentional task. Alcohol (equal to ˜0.5 g/L of blood) facilitated communication, but basically it had no effect on any of the psycho-technical performance tests. For the latter, an interaction was observed between when the test was done and type of beverage consumed. Alcohol appears to alter the expected change in performance in the retest situation. The results suggest that the bodys sensitivity to a measured quantity of alcohol differs according to the cognitive processes involved.