Evidence for Multiple Rhythmic Skills

Rhythms, or patterns in time, play a vital role in both speech and music. Proficiency in a number of rhythm skills has been linked to language ability, suggesting that certain rhythmic processes in music and language rely on overlapping resources. However, a lack of understanding about how rhythm skills relate to each other has impeded progress in understanding how language relies on rhythm processing. In particular, it is unknown whether all rhythm skills are linked together, forming a single broad rhythmic competence, or whether there are multiple dissociable rhythm skills. We hypothesized that beat tapping and rhythm memory/sequencing form two separate clusters of rhythm skills. This hypothesis was tested with a battery of two beat tapping and two rhythm memory tests. Here we show that tapping to a metronome and the ability to adjust to a changing tempo while tapping to a metronome are related skills. The ability to remember rhythms and to drum along to repeating rhythmic sequences are also related. However, we found no relationship between beat tapping skills and rhythm memory skills. Thus, beat tapping and rhythm memory are dissociable rhythmic aptitudes. This discovery may inform future research disambiguating how distinct rhythm competencies track with specific language functions.     

Spontaneous rhythm discrimination in a mammalian vocal learner

Rhythm and vocal production learning are building blocks of human music and speech. Vocal learning has been hypothesized as a prerequisite for rhythmic capacities. Yet, no mammalian vocal learner but humans have shown the capacity to flexibly and spontaneously discriminate rhythmic patterns. Here we tested untrained rhythm discrimination in a mammalian vocal learning species, the harbour seal (Phoca vitulina). Twenty wild-born seals were exposed to music-like playbacks of conspecific call sequences varying in basic rhythmic properties. These properties were called length, sequence regularity, and overall tempo. All three features significantly influenced seals'' reaction (number of looks and their duration), demonstrating spontaneous rhythm discrimination in a vocal learning mammal. This finding supports the rhythm–vocal learning hypothesis and showcases pinnipeds as promising models for comparative research on rhythmic phylogenies.     

Peculiarities of EEG in hard-of-hearing children of primary school age

Electroencephalographic examination of 7-to 9-year-old children with sensorineural deafness of degrees II and III included EEG recording in the resting state, in the course of reaction of activation (at opening of the eyes), under conditions of rhythmic photostimulation with frequencies of 4, 6, 9, and 12 sec⁻¹ and under those of the hyperventilation test. The results allow us to conclude that systems responsible for generation of EEG in hard-of-hearing children demonstrate some functionally immaturity. The following facts confirm the above conclusion. As compared with the norm, greater normalized spectral powers (SPs) of the delta and theta rhythms, a higher intensity of electrogenesis (integral power of oscillations) within all frequency ranges, and a smaller mean frequency of the dominant rhythm were typical of hard-of-hearing children. In these children, the reaction of activation in the majority of cases looked like incomplete suppression of the alpha rhythm. Upon rhythmic photostimulation, hard-of-hearing boys and girls demonstrated following of the rhythm at frequencies of 4 and 6 sec⁻¹ while children with normal hearing demonstrated that at 9 and 12 sec⁻¹ frequencies. The characteristics of EEG reactions under the conditions of the hyperventilation test reflected the immaturity of the fronto-thalamic controlling system, as well as certain dysfunction of lower brainstem regions in children with disorders of hearing. Neirofiziologiya/Neurophysiology, Vol. 40, No. 2, pp. 137–146, March–April, 2008.     

THE LANGUAGE-HANDICAPPED CHILD—Coordinated Evaluation by Physicians and Educators

Seventy children were studied during 1959 in a special school program because of major language problems. A team of medical and educational personnel studied each child during a ten-day school enrollment. The results of the medical and educational studies were of great value in establishing the correct diagnosis and devising a suitable educational program for the children.     

High-resolution measurements of face-to-face contact patterns in a primary school

Background

Little quantitative information is available on the mixing patterns of children in school environments. Describing and understanding contacts between children at school would help quantify the transmission opportunities of respiratory infections and identify situations within schools where the risk of transmission is higher. We report on measurements carried out in a French school (6–12 years children), where we collected data on the time-resolved face-to-face proximity of children and teachers using a proximity-sensing infrastructure based on radio frequency identification devices.

Methods and Findings

Data on face-to-face interactions were collected on Thursday, October 1^st and Friday, October 2^nd 2009. We recorded 77,602 contact events between 242 individuals (232 children and 10 teachers). In this setting, each child has on average 323 contacts per day with 47 other children, leading to an average daily interaction time of 176 minutes. Most contacts are brief, but long contacts are also observed. Contacts occur mostly within each class, and each child spends on average three times more time in contact with classmates than with children of other classes. We describe the temporal evolution of the contact network and the trajectories followed by the children in the school, which constrain the contact patterns. We determine an exposure matrix aimed at informing mathematical models. This matrix exhibits a class and age structure which is very different from the homogeneous mixing hypothesis.

Conclusions

We report on important properties of the contact patterns between school children that are relevant for modeling the propagation of diseases and for evaluating control measures. We discuss public health implications related to the management of schools in case of epidemics and pandemics. Our results can help define a prioritization of control measures based on preventive measures, case isolation, classes and school closures, that could reduce the disruption to education during epidemics.     

High incidence of profound deafness in an isolated community

In a Muslim Israeli Arab village, different types of hearing loss affect some 2% of the inhabitants. Most cases of profound deafness are due to recessive mutations in the Connexin-26 gene. Since in this community, marriages are by preference within the family (consanguineous), for many of the couples from the village the risk for an affected child is high. There are 30 families living in the village in which both parents have normal hearing and at least one child has a profound hearing defect. In these families, the birth of a child with profound deafness did not change family planning. The rate of marriage was similar for the siblings of deaf children as for other individuals in the village. The major problems were encountered by the deaf individuals themselves; in particular, most of the women were not married. Because of the distinctive nature of this particular problem, different types of screening programs were envisaged. However, all of them are problematic. Therefore, as a first step it was decided to begin a program including individual genetic counseling together with education of the entire population on practical aspects of human genetics.     

Variation of behavioral and physiological variables in children attending kindergarten and primary school

Twenty-one children aged 5-6 years (mean age: 71.2 months; S.D. = 2.7) were videotaped in 4 different kindergartens throughout the school day for a period of one week. Eighteen of these children were then followed up after the summer holidays and videotaped for one week while attending the first year of primary school. The behaviors measured for each child were yawning and general motor activity. It was found that: (1) The frequency of yawning appears to be 5 times higher in the first year of primary school than in the last year of kindergarten; (2) Throughout the school-day the percentage of yawning children is higher in the first year of primary school, with the exception of the 1400-1430 period; (3) In the first year of primary school, the percentage of yawning children and the frequency of yawning peak between 900 and 930 and 1430 and 1500; (4) In this school institution the percentage of children who get up from their chair and spontaneously move above increases from the beginning to the end of each school-day. Three cardio-vascular variables were investigated in 17 children of the sample population: heart rate, systolic and diastolic blood pressure. We found that: (1) The lowest values for heart rate in the first year of primary school are in agreement with the classical data of child development, as the children are 5-6 months older than in the last year of kindergarten. However, this is not the case at 1400 when the heart rate peaks at a higher level in the first year of primary school; (2) If the evolution in time of the blood pressure agrees in both institutions with the classical data of human chronobiology, i.e. the maximum values at 1400, the differences in mean level at all times during the school day between both institutions do not agree with what is commonly accepted, i.e. an increase in blood pressure with age; (3) The amplitude of the variations of the heart rate and blood pressure from one 30-min period to another throughout the school day is significantly higher in primary school. The comparison of the data obtained in both school institutions suggests that the observed differences are related to sharp modifications in school rhythms and constraints when the children go from the last year of kindergarten to the first year of primary school.     

Introduction

Twenty-one children aged 5-6 years (mean age: 71.2 months; S.D. = 2.7) were videotaped in 4 different kindergartens throughout the school day for a period of one week. Eighteen of these children were then followed up after the summer holidays and videotaped for one week while attending the first year of primary school. The behaviors measured for each child were yawning and general motor activity.

It was found that: (1) The frequency of yawning appears to be 5 times higher in the first year of primary school than in the last year of kindergarten; (2) Throughout the school-day the percentage of yawning children is higher in the first year of primary school, with the exception of the 1400-1430 period; (3) In the first year of primary school, the percentage of yawning children and the frequency of yawning peak between 900 and 930 and 1430 and 1500; (4) In this school institution the percentage of children who get up from their chair and spontaneously move above increases from the beginning to the end of each school-day.

Three cardio-vascular variables were investigated in 17 children of the sample population: heart rate, systolic and diastolic blood pressure.

We found that: (1) The lowest values for heart rate in the first year of primary school are in agreement with the classical data of child development, as the children are 5-6 months older than in the last year of kindergarten. However, this is not the case at 1400 when the heart rate peaks at a higher level in the first year of primary school; (2) If the evolution in time of the blood pressure agrees in both institutions with the classical data of human chronobiology, i.e. the maximum values at 1400, the differences in mean level at all times during the school day between both institutions do not agree with what is commonly accepted, i.e. an increase in blood pressure with age; (3) The amplitude of the variations of the heart rate and blood pressure from one 30-min period to another throughout the school day is significantly higher in primary school.

The comparison of the data obtained in both school institutions suggests that the observed differences are related to sharp modifications in school rhythms and constraints when the children go from the last year of kindergarten to the first year of primary school.     

Clusters structure of psychomotor and coordination sphere of primary school children

The main objective of our research is characterization of various motor profiles among primary school age children. We examined 89 Moscow schoolchildren of 8-10 years old, not involved in sports. We analyzed 25 indices from psychomotor, psychophysiologic, posturography and locomotor testing during our research. Children were divided in 4 groups according to its motor coordination character similarity by applying cluster analysis (k-means method). Thereby we obtained 4 clusters which, as we suppose, can be identified as different types of motor coordination or "individual motor profiles" of 8-10 years old children. The results of our research shows that there are no significant differences in age, gender, body composition within clusters, thus it can be used during sport-selection process. The most typical features of 1st cluster representatives are: the ability to anticipate and a high wrist speed; the 2nd cluster representatives are more successful in rapid, rhythmic, automatic actions, based on a mechanism of intrinsic programming. Representatives of the 3rd cluster are notable for a low level of postural control, smooth, accurate and rhythmic arm actions based on a visual feedback, and advanced sense of tempo and space sense. Representatives of the 4th cluster shows highest level of development of coordination ability, which are significant for them in reaching results in various hard-coordination sports and labor activities.     

Effect of putative neuromodulators on rhythmic buccal motor output in Lymnaea stagnalis

The effects of a variety of neuromodulator substances on rhythmic motor output and activity in neurons in the feeding circuitry of Lymnaea stagnalis were examined. Each neuromodulator produced a unique combination of effects at different levels in the network: i.e., pattern-generating interneurons (N1, N2, and N3), an identified higher-order interneuron (cerebral giant cell, CGC), and buccal motoneurons. 5-Hydroxytryptamine, acetylcholine, and FMRFamide all inhibited rhythmic motor activity. However, this was achieved in different ways. Dopamine changed the nature of rhythmic activity from one in which N2 interneuronal activity was predominant ("N2 rhythm") to a feeding rhythm. Dopamine was the only substance capable of activating the feeding rhythm. Activity in the CGC was increased by 5-hydroxytryptamine, dopamine, and acetylcholine and reduced by FMRFamide. Differential responses in buccal motoneurons were also observed. The results are discussed in relation to previous work on other species and also in terms of the selection of different patterns of motor output by neuromodulators.     

Mobile hearing program in central rural Manitoba.

A mobile hearing program was developed to detect and alleviate deafness and rehabilitate deaf individuals in rural Manitoba. The first project was established in central Manitoba in December 1973 for children, whose school performance can be affected by minimal hearing loss. Volunteers from the community, trained by an audiologist, conduct screening procedures, and children with possible hearing impairment receive audiologic and otolaryngologic assessment. Close clinical liaison between audiologist and otologist is important.     

内源性一氧化碳参与呼吸节律调节

本文旨在探讨内源性一氧化碳（carbon monoxide,CO）对呼吸节律的调节作用。采用新生Sprague—Dawley大鼠,制备离体延髓脑片标本,分别灌流CO、血红素氧合酶（heme oxygenase,HO）底物高铁血红素（hemin）和HO抑制剂ZnPP-9,观察舌下神经根呼吸样传出放电节律的变化。实验分为5组：单纯人工脑脊液（artificial cerebrospinal fluid,ACSF）对照组、ZnPP-9组、外源性CO组、Hemin组和ZnPP-9＋Hemin组。结果如下：在ZnPP-9组,舌下神经根节律性放电频率（discharge frequency,DF）增快（P〈0．05）;在外源性CO组,舌下神经根节律性DF减慢（P〈0.05）;在Hemin组和ZnPP-9＋Hemin组,舌下神经根节律性DF增快（P〈0．05）。结果表明,内源性CO对呼吸节律可能具有调节作用。     

Ultradian, Circadian and Circannual Rhythms of Blood Glucose and Injected Insulins Documented in Six Self-Controlled Adult Diabetics

The aim of the study was to document during one to two years individual rhythmic patterns in blood glucose and injected insulin in self-controlled insulin dependent (C-peptide negative) diabetics with home blood glucose monitoring. Two females and four males with diurnal activity from 0700 to 2300 self-determined their blood glucose three to six times a day over a period of 12-27 months. Circadian and ultradian rhythms were analysed for each subject on a monthly basis to document annual rhythms. Blood glucose (BG) estimated circadian acrophases were located between 2200 and 0300 for all patients and months with few exceptions. A correlation was found between circadian mesors and amplitudes of BG in four subjects. Annual changes in BG were validated for each subject with large interindividual differences in peak times. The individual mean of injected insulin (II) varied from 40 to 80 iU with annual changes validated for each subject. A group pattern was observed with a peak time either in the autumn (four patients) or in the summer (two patients). A circadian rhythm of II was detected in almost all monthly means and for all patients. Locations of computed peak time φ of II exhibited a great stability for a given individual but large interindividual differences. Thus the rather constant φ location of BG for all subjects contrasted with interindividual differences in φ locations of II. These results suggest that rhythmic changes in BG and II should be recognized when forming a realistic strategy for timing and dosing time(s) of insulin.     

Regulation of the Photosynthesis Rhythm in Euglena gracilis: I. Carbonic Anhydrase and Glyceraldehyde-3-Phosphate Dehydrogenase Do Not Regulate the Photosynthesis Rhythm

A circadian rhythm of O₂ evolution has been found in Euglena gracilis, Klebs strain Z. The rhythm persists for at least 5 days in constant dim light and temperature, but damps out in constant bright light. The phase of this rhythm can be shifted by a pulse of bright light and the period length is not changed over a 10 C span of growth temperature.

The O₂ evolution rhythm is found in both logarithmic and stationary phase cultures, but CO₂ uptake is clearly rhythmic only in stationary phase cultures.

The activity of glyceraldehyde-3-phosphate dehydrogenase was not rhythmic as previously reported (Walther and Edmunds [1973] Plant Physiol. 51: 250-258). Carbonic anhydrase activity was rhythmic when the cultures were maintained under a light-dark cycle with the highest enzyme activity coinciding with the fastest rate of O₂ evolution. However, the rhythm in carbonic anhydrase activity disappeared under constant conditions. Changes in the activities of these two enzymes are therefore not responsible for the rhythmic changes in photosynthetic capacity.

     

Investigation of a circannual rhythm in nasopharyngeal airway patency in children

We have studied nasopharyngeal adenoids on standardized cephalometric radiograms of 25 children in each season. While individual subjects showed changes ranging from 1-17% throughout the year, a synchronized circannual rhythm could be described for the girls only. Similar changes were observed in boys, although a synchronized group rhythm could not be ascertained. No clear explanation for this apparent sexual dimorphism is known at this time, but different hormonal influences are likely. Evaluation of the nasopharyngeal airway (NPA) patency is thus affected by the season in which a cephalogram is taken. It should be noted that due to the described circannual rhythmicity, a single determination of the adenoid masses may be an insufficient and misleading indicator of the NPA obstruction. Etiology and clinical significance of these rhythmic changes need to be explored further.     

Disturbance of Circadian Rhythms in Analgosedated Intensive Care Unit Patients with and without Craniocerebral Injury

Melatonin, cortisol, heart rate, blood pressure, spontaneous motor activity, and body temperature follow stable circadian rhythms in healthy individuals. These circadian rhythms may be influenced or impaired by the loss of external zeitgebers during analgosedation, critical illness, continuous therapeutic intervention in the intensive care unit (ICU), and cerebral injury. This prospective, observational, clinical study examined 24 critically ill analgo‐sedated patients, 13 patients following surgery, trauma, or acute respiratory distress (ICU), and 11 patients with acute severe brain injury following trauma or cerebral hemorrhage (CCI). Blood samples for the determination of melatonin and cortisol were obtained from each patient at 2 h intervals for 24 h beginning at 18:00 h on day 1 and ending 16:00 h on day 2. Blood pressure, heart rate, body temperature, and spontaneous motor activity were monitored continuously. Level of sedation was assessed using the Ramsey Sedation Scale. The severity of illness was assessed using the APACHE‐II‐score. The time series data were analyzed by rhythm analysis with the Chronos‐Fit program, using partial Fourier series with up to six harmonics. The 24 h profiles of all parameters from both groups of patients were greatly disturbed/abolished compared to the well‐known rhythmic 24 h patterns in healthy controls. These rhythm disturbances were more pronounced in patients with brain injury. The results of this study provide evidence for a pronounced disturbance of the physiological temporal organization in ICU patients. The relative contribution of analgosedation and/or brain injury, however, is a point of future investigation.     

Disturbance of circadian rhythms in analgosedated intensive care unit patients with and without craniocerebral injury

Melatonin, cortisol, heart rate, blood pressure, spontaneous motor activity, and body temperature follow stable circadian rhythms in healthy individuals. These circadian rhythms may be influenced or impaired by the loss of external zeitgebers during analgosedation, critical illness, continuous therapeutic intervention in the intensive care unit (ICU), and cerebral injury. This prospective, observational, clinical study examined 24 critically ill analgo-sedated patients, 13 patients following surgery, trauma, or acute respiratory distress (ICU), and 11 patients with acute severe brain injury following trauma or cerebral hemorrhage (CCI). Blood samples for the determination of melatonin and cortisol were obtained from each patient at 2 h intervals for 24 h beginning at 18:00 h on day 1 and ending 16:00 h on day 2. Blood pressure, heart rate, body temperature, and spontaneous motor activity were monitored continuously. Level of sedation was assessed using the Ramsey Sedation Scale. The severity of illness was assessed using the APACHE-II-score. The time series data were analyzed by rhythm analysis with the Chronos-Fit program, using partial Fourier series with up to six harmonics. The 24 h profiles of all parameters from both groups of patients were greatly disturbed/abolished compared to the well-known rhythmic 24 h patterns in healthy controls. These rhythm disturbances were more pronounced in patients with brain injury. The results of this study provide evidence for a pronounced disturbance of the physiological temporal organization in ICU patients. The relative contribution of analgosedation and/or brain injury, however, is a point of future investigation.     

Health surveillance of preschool children: four years' experience.

OBJECTIVES--To monitor the implementation of a programme of health surveillance for preschool children and measure its effect on child health. DESIGN--Regular reporting to primary care teams of their own performance, and determining the overall effect of the programme on children in the district. SETTING--All practices in Northumberland health district. SUBJECTS--All children of preschool age in Northumberland (3600 births each year). MAIN OUTCOME MEASURES--Proportion of eligible children immunised and screened for abnormalities. Age at diagnosis of congenital deafness, cerebral palsy, and special educational needs. RESULTS--Over 90% of eligible children were covered by the health surveillance scheme. Child health improved over the four years after the scheme was implemented. Uptake of immunisation against measles rose from 68% to 93% of eligible children, and the average age at which congenital deafness was diagnosed fell to 9 months. CONCLUSIONS--Maintaining the effectiveness of a surveillance programme and reporting this back to primary health care teams are processes which themselves improve health.     

Congenital Perceptive Deafness: Role of Intrauterine Rubella

Rubella antibody was detected in 85 (61%) of 139 children aged from 6 months to 7 years with congenital perceptive deafness. Of the 112 children who were aged under 4 years 61 (54%) had rubella antibody (seropositive) compared with 7·1% in randomly selected children of the same age. A close correlation was found between the presence of antibody in children with perceptive deafness and (1) a maternal history of rash or contact in early pregnancy, and (2) with the presence of other rubella-type defects. Intrauterine rubella was thought to be the cause of the deafness in 82 (59%) of the 139 children, in 60 of whom deafness was the only rubella defect detected. Thus intrauterine rubella should be considered a likely cause of congenital perceptive deafness in a child under 4 years in whom rubella antibody is present.     

Immediate and Prolonged Effects of Drugs on Rhythm's Characteristics: Relevance to Chronochemotherapy

Four groups of mice were injected with vincristine, each at a different time, for ten successive days. Mortality and daily pattern of peripheral white blood cells (WBC) count were monitored immediately and at various times after the last injection. The results demonstrated that (1) drug administration time dependency was observed in rate of death, recorded for 80 days following the injections; (2) the time of drug administration affected the parameters of WBC count rhythm, and (3) there were differences between immediate effects upon the rhythm parameters (monitored one day after the last injection) to those measured at succeeding times (on days 8 and 15 after injections cessation). The results emphasize the need to consider continuous post administration rhythm changes, especially when scheduling repeated chronotherapeutics, where variables which serve for toxicity-diagnosis are rhythmic in nature.