The dynamics of the direct current potentials of the brain during sustained attention in 10-11-year-old children

The dynamics of direct current potentials of the brain was studied in 10-11-year-old children during sustained attention to successive presentation of series of Shulte tables. Children were examined twice: before and after the series of training to fast reading. A gradual increase in the level of direct current potentials during sustained attention was observed. The increase was more pronounced in children with excessive than in children with moderate reactions to the loading. After the series of training to fast reading, the increase in the level of direct current potentials was reduced in both groups. This aftertraining neurophysiological phenomenon was combined with a transformation of psychophysiological characteristics: a decrease in the time of viewing of Shulte tables and increase in the speed of reading. It is suggested that the shifts of direct current potentials reflects the dynamics of intensity of the cerebral energy metabolism.     

The ontogeny of the neurophysiological mechanisms of stereognosis: An EEG study

Age-related characteristics of the systemic organization of intra- and interhemispheric interactions during a stereognostic task (tactile shape recognition with the right or left hand) were studied in adults and children aged five to six, seven to eight, and nine to ten years. A combined pattern of cortical interactions was found in adults. It was expressed in a considerable enhancement of relationships between cortical bioelectric potentials compared to the baseline accompanied by a substantial increase in the intensity of the systemic interactions between anterior and posterior cortical areas. This pattern was revealed by both coherence and cross-correlation analyses of the electroencephalogram (EEG). In the EEGs of children, the enhancement of interhemispheric relationships was observed at an age as early as five to six years and was the highest in seven- to eight-year-old children, whereas the increase in the cross-correlation of cortical bioelectric potentials in the frontal—occipital direction developed gradually, approaching the definitive level typical of adults by the age of nine to ten years. The results suggest that the central mechanisms of stereognosis, a function important for manual and occupational activities, gradually develop during postnatal ontogeny. Heterochronic involvement of intra- and interhemispheric interactions in the performance of stereognostic task may be related to gradual, heterochronic myelination of commissural and associative pathways.     

Formation of the functional organization of the cerebral cortex at rest in young schoolchildren varying in the maturity of cerebral regulatory systems: I. Analysis of EEG spectral characteristics in the state of rest

Spectral correlation analysis of the EEG was used to study the organization of the rhythmic electrical activity (EA) of the cerebral cortex in normal children aged seven to eight and nine to ten years and children with the two types of functional immaturity of cerebral regulatory systems most common at this age, namely, fronto-thalamic regulatory system immaturity (IFTS) and brainstem nonspecific activation system immaturity (deficiency) (DNA). Statistical comparison (ANOVA) of these groups of children with respect to the absolute and relative α-and ?-band spectral powers of the background EEGs of 12 cortical areas showed the specific features of the effects of functional immaturity of regulatory systems at different levels on the cortical rhythmic EA pattern at rest. DNA led to a significant increase in the absolute spectral power of α and ? waves recorded in all derivations in both age groups, which indicated a generalized decrease in cortex activation in these children. IFTS caused a significant decrease in the relative strength of α waves and an increase in the strength of ? waves. Taking into account the results of ontogenetic studies, this may be regarded as evidence for a relative underdevelopment of cortical rhythm-generating networks. The absolute spectral powers of both α and ? waves were decreased in all groups of children by nine to ten years of age, which indicated that nonspecific activation was enhanced in the age interval studied. Significant changes were observed in children with functional immaturity of regulatory systems. In children with DNA, the age-related increase in cortex activation was expressed as a significant increase in the α-rhythm peak frequency. In children with IFTS, by nine to ten years of age, both the absolute and relative strengths of ? waves were decreased in most cortical areas studied, which may be regarded as the progressive formation of cortical rhythm-generating mechanisms.     

Psychophysiological indices in six-to eight-year-old children under information load depending on anxiety as a stable individual characteristic

The study of psychophysiological indices in children aged six to eight years under information loads of various complexity showed that anxious subjects were characterized by a high level of nonspecific activation at rest and a shift of the autonomic balance towards a relative domination of the tone of the sympathetic division of the autonomic nervous system (ANS). The information load in the “auto-rate” mode caused in children aged six to eight years an increase in the level of nonspecific activation and the activity of sympathetic regulation and an inhibition of parasympathetic regulation. An information load in the “maximum rate of work” mode caused a decrease in the quantitative and qualitative indices of mental activity in comparison with that under comfortable conditions and a subsequent increase in autonomic shifts and the level of situational anxiety. The decrease in the efficiency of intellectual work performed at a maximum rate against the background of a high level of nonspecific activation and an increase in situational anxiety in both groups apparently reflected an increase in the activity of the modulating cerebral system due to the domination of the nonproductive activation system related to defensive behavior. At the same time, in children with a high personal anxiety, autonomic manifestations of activation and situational anxiety in both modes of work were more distinct and the efficiency of work lower than in subjects with a low anxiety. This indicates that, in anxious children, due to the excess activation of the sympathetic division of the ANS, the information load has a higher physiological cost. Thus, children with a high level of personal anxiety under intense information loads are characterized by a larger increase in the activity of the sympathetic division of the ANS and the attenuation of the effect of the parasympathetic division; a considerable increase in situational anxiety; low efficiency of activity; and, hence, its high physiological cost.     

Analysis of visuospatial activity in preschool children with attention deficit disorder

Parameters of visuospatial components of mental activity were studied in Mexican children aged 5–6 years with attention deficit disorder. The control group (norm) consisted of preschool children of the same age who attended municipal kindergartens. Neuropsychological methods specially developed and adapted for Mexican children were used. The results testified to prominent impairments of the parameters of spatial analysis and synthesis and of the formation level of object imagery, suggesting functional weakness of the posterior associative (TPO) cortical areas of both hemispheres. The results elucidate specific difficulties in cognitive activity and other impairments in children with attention deficit disorder.     

Functional maturation of the brain and formation of the neurophysiological mechanisms of selective voluntary attention in young schoolchildren

A particular role was demonstrated for functional maturation of the frontothalamic system (FTS) of the brain in forming the cerebral organization of selective voluntary attention in ontogeny. Analysis of the coherence of the rhythmic components of the EEG α range in adults and seven-to eight-and nine-to ten-year-old children showed that, if the functional state of the control structures corresponds to the age, the formation of the neurophysiological mechanisms selectively modulating cortical activity and supporting selective tuning of the cerebral structures to the cognitive task is completed by the age of seven or eight years. Unlike adults, children demonstrated no interhemispheric features of the intercenter integration of cortical zones in the prestimulus period of voluntary attention. Children with a functionally immature FTS lacked selective specific integration of cortical zones in the pretuning period. The deficit of selective modulation of cortical activity in children with a functionally immature FTS is considered as the neurophysiological factor that delays the formation of voluntary attention and voluntary control of activity and, finally, leads to learning difficulties.     

Fetal alcohol spectrum disorders among children in a Brazilian orphanage

Background: The objective was to investigate the frequency of fetal alcohol spectrum disorders (FASD) and ophthalmologic anomalies in orphanage children in Brazil. Methods: A prospective study was performed on 94 children living in an orphanage in Brazil. The children were examined by a multidisciplinary team consisting of specialists in pediatrics, neurology, psychology, neuropsychiatry, and ophthalmology. Results: The main reasons for living in the orphanage, in 61% of the children, were negligence, child abuse, and abandonment. Of all the children studied, 50% had mothers with known alcohol abuse and 47% had one or more diagnoses of neurodevelopmental/behavioral and/or cognitive deficits. General developmental delay was found in 18%, intellectual disability in 3%, cognitive impairment in 27%, attention‐deficit/hyperactivity disorder in 14%, and autism in 3%. Altogether 17% had FASD, comprising three children with fetal alcohol syndrome (FAS), six with partial FAS, and seven with alcohol‐related neurodevelopmental disorder. 16% had ophthalmological findings such as poor vision, strabismus, and dysmorphology of the optic nerves. Twenty‐eight children (30%) were adopted from the orphanage; of these, six had FASD (two FAS, three partial FAS, one alcohol‐related neurodevelopmental disorder), five had attention‐deficit/hyperactivity disorder, and eight had developmental delay. Conclusion: Nearly half of the children living in the orphanage had neurodevelopmental disorders and a considerable number showed signs of damage from prenatal alcohol exposure. A broader look at the problem of FASD in Brazil and other South American countries is desirable to document the burden of disease and provide data for targeting prevention efforts. Birth Defects Research (Part A) 103:178–185, 2015. © 2014 Wiley Periodicals, Inc.     

The elusive diploic veins: anthropological and anatomical perspective

Diploic veins (Canales diploicae), which were identified in dogs by Dupuytren more than 200 years ago (Hecker [1845] Die anatomische Verhaltnisse und Krankheiten der Venae diploicae und Vasa emissaria. Erfahrungen und Abhandlungen im Gebiete der Chirurgie und Augenheilkunde. Erlangen), have remained inadequately understood and scantily referenced in the anatomical and anthropological literature. The tunnels formed by diploic veins are among the few known skeletal markers of soft tissue alteration. Protected by two bony laminae, diploic vein tunnels often resist postdepositional destruction and may provide a new way to assess living and extinct hominid populations. This basic research was carried out to enable future utilization of the diploic venous channels in anthropologic research. In the present study, diploic venous channels were observed radiographically in 108 human adults aged 19 years and above, 18 infants and children aged 1-18 years (Hamann-Todd Osteological Collection), eight fetuses aged 7-9 months (the Johns Hopkins Collection), and seven nonhuman primates (Hamann-Todd Osteological Collection). In addition, seven documented cases of parents and children were radiographed for genetic evaluation (Osteological Collection of The Hungarian Natural History Museum). Five distinct diploic distribution patterns were identified and described in this study. This was at variance with the impressions reported in dissection-based studies. Independence of diploic vein pattern from demographic (gender and age) and size factors and their tendency to be symmetrical make them amenable and reliable traits for skeletal population study. Diploic vein patterns appeared to be more complicated in humans than in nonhuman primates, raising the possibility of future phylogenetic applications.     

Different Visual Preference Patterns in Response to Simple and Complex Dynamic Social Stimuli in Preschool-Aged Children with Autism Spectrum Disorders

Eye-tracking studies in young children with autism spectrum disorder (ASD) have shown a visual attention preference for geometric patterns when viewing paired dynamic social images (DSIs) and dynamic geometric images (DGIs). In the present study, eye-tracking of two different paired presentations of DSIs and DGIs was monitored in a group of 13 children aged 4 to 6 years with ASD and 20 chronologically age-matched typically developing children (TDC). The results indicated that compared with the control group, children with ASD attended significantly less to DSIs showing two or more children playing than to similar DSIs showing a single child. Visual attention preference in 4- to 6-year-old children with ASDs, therefore, appears to be modulated by the type of visual stimuli.     

青海省2006年14岁以下儿童百日咳白喉破伤风抗体水平监测

调查青海省0~14岁健康儿童百日咳、白喉、破伤风抗体水平,抽样评价预防接种质量。在全省六州一地一市各选择1个县,对0~14岁健康儿童进行抗体检测。结果显示,百日咳、白喉、破伤风抗体阳性率分别为93.42%、94.96%和92.93%。不同地区0~14岁健康儿童百日咳、白喉和破伤风抗体阳性率虽有差别,但都达到较高的抗体水平;个别地区抗体水平低,说明青海省儿童计划免疫工作存在薄弱环节。     

Anxiety and methylphenidate in attention deficit hyperactivity disorder: a double-blind placebo-drug trial

To examine the relationship between attention and anxiety and the response to methylphenidate in children with attention deficit hyperactivity disorder (ADHD), a total of 57 boys, between the ages of 7-12?years, were assessed for their attention and level of anxiety. Methylphenidate was administered for a week in a randomized double-blind drug/placebo-drug cross-over design. The levels of anxiety were evenly distributed between the inattentive and hyperactive/impulsive types. Anxiety was significantly correlated with the attention as reported by both teachers and parents. The response to methylphenidate was inversely correlated with the reported anxiety level only in boys with the hyperactive/impulsive and combined types. The higher the level of anxiety, the lower level of response to methylphenidate was observed. In the assessment and treatment of children with ADHD, the level of anxiety should be evaluated and taken into account while planning and monitoring treatment regiment.     

Sex specificity of the spatiotemporal organization of brain bioelectric potentials in adults and five- to six-year-old children in a state of quiet wakefulness

Correlation and coherence analyses of EEG recordings from 26 children aged five to seven years (12 boys and 14 girls) as compared to 33 adult subjects (18 women and 15 men) has been carried out to study the topical features of the spatial structure of EEG distant interactions. A higher level of EEG intrahemispheric interactions in the posttemporal and frontal areas of the left hemisphere has been found in men as compared to women in whom the prevalence of interhemispheric interactions due to the expressed EEG interactions in the bilaterally symmetric areas of both hemispheres has been found. A different type of sex-related differences in the systemic organization of interregional interactions of cortical potentials, as compared to adults, has been found in preschool children. In particular, a higher prevalence of EEG distant interactions has been found in those areas of the left hemisphere, the EEG interactions of which were higher in adult men. The data show that a distinct sexual dimorphism of interregional interactions of cortex potentials in adult subjects and children is formed due to the topology of the different EEG distant interactions differing in men and women. Investigations of the sex specificity of the spatiotemporal organization of brain bioelectric potentials in children can promote understanding of the sexual identity role in development of human brain systemic activity.     

Clinical and immunological effect of vaccination against Haemophilus influenzae, type B, in children with disorders of the nervous system

Observations on 277 children aged 3 months to 4 years with lesions of the nervous system, immunized with vaccine Act-HIB (Aventis Pasteur, France), were carried out in groups of children. The significant decrease of the level of Hib nasopharyngeal carrier state in 3.3 times and the decrease of total morbidity in acute infections of respiratory and ENT organs in 2.7 times occurred after immunization was revealed. The immunological effect of immunization on the level of protective titers against H. influenzae, type b, in children with organic CNS lesions in children was shown.     

Formation of the functional organization of the cerebral cortex at rest in young schoolchildren varying in the maturity of cerebral regulatory systems: II. Analysis of EEG α-rhythm coherence

Coherence (COH) of rhythmic components of the EEG α rhythm at rest was analyzed to demonstrate that the maturation of deep regulatory systems (RSs) of the brain at different levels substantially affected the functional organization of the cerebral cortex and the time course of the formation of intercentral connections in young schoolchildren. The specific effect of fronto-thalamic regulatory system immaturity (FRSI) was a decrease in the α-rhythm COH predominantly in neighboring left-hemispheric derivations of foci in the anterior temporal area. A deficit of nonspecific activation had the strongest effect on the α-rhythm integration of right-hemispheric areas, although this effect was less distinct than that of FRSI and remained only as a tendency by the age of nine to ten years. Children with normal and functionally immature cerebral RSs differed from each other with respect to age-related changes in the corticocortical connections, especially in the left hemisphere. In the norm, intense growth of functional connections in the left hemisphere ceased in the period between seven to eight and nine to ten years of age; in contrast, children with RS immaturity exhibited a trend towards an increasingly greater amount of these connections in both hemispheres, which, apparently, corresponded to an earlier stage of ontogeny.     

Age-Related Features of Morphological and Functional Development of Myocardium in Children of Five to Nine Years

Age-related features of the morphological and functional development of the myocardium were studied by echo- (EchoCG) and electrocardiography (ECG) in 200 children five to nine years of age. The most intensive anatomical development of myocardium was observed at the age of five to seven years, and a significant increase in cardiac output was observed at the age of eight to nine years both in boys and girls. The ECG amplitude and time parameters significantly changed from of five to nine years of age and were most pronounced at the age of seven to eight years. Different changes in cardiac rhythm and excitation conduction as well as repolarization and metabolic disturbances in the myocardium were often observed at this age. Static physical exercise caused marked changes in bioelectric activity of the myocardium. Two types of central circulatory responses to static exercise were found: an increase and a decrease in cardiac output. The mechanisms of cardiac rhythm regulation, which caused an increase in the stroke volume as a response to exercise, were different in children from five to nine years old. At the age of five to six years the homeometric mechanism was a crucial factor in the increase in stroke volume as a response to exercise, and at the age of seven to nine years both homeo- and heterometric mechanisms of cardiac rhythm regulation were very important.     

Structural and functional organization of a developing brain and formation of cognitive functions in child ontogeny

Results of multidisciplinary studies, including neuromorphological, neurophysiological, neuropsychological, and psychphysiological studies, are reviewed. They allow the brain mechanisms of cognition formation and development during maturation to be identified. The role of regulatory (modulatory) brain systems in forming the cognitive function in the child is demonstrated. Data on considerable changes in the brain systems responsible for the development of cognitive functions in children between the ages of five to six and seven to eight years are presented. At this age, the morphological and functional maturations of the frontal cortical areas and their descending connections with other cerebral structures increase the efficiencies of arbitrary selective attention, learning the activity program, inhibition of spontaneous responses, and regulation and organization of activity, i.e., the functions that are important for successful schooling.     

Bioelectric brain activity during visual perception of verbalized and nonverbalized stimuli in seven-to eight-year-old schoolchildren

Neurophysiological mechanisms of visual perception of verbalized and nonverbalized stimuli have been studied in girls (n = 89) and boys (n = 109) aged seven to eight years. It has been shown that, in children of this age, neurophysiological mechanisms of the visual perception system during the selection of verbalized and nonverbalized stimuli have similar organizations of functional rearrangements and are characterized by the general involvement of cortical areas and by the lack of clear specialization of the cerebral hemispheres. However, the choice of nonverbalized visual stimuli is characterized by a more pronounced generalization of the functional interaction between cortical areas and by the increased spectral power of the EEG’s high-frequency components in anterior associative areas. The increased spatial synchronization in the EEG θ- and β bands in the frontal areas emphasizes the contribution of these structures to the analysis and processing of visual stimuli at this stage of development. Differences in the neurophysiological mechanisms of visual perception in boys and girls have been detected. Spatial and temporal organizations of bioelectric activity (BEA) of the brain in girls performing visual tasks is characterized by a stronger and more varied ipsi- and contralateral statistical relationships in the fronto-occipital direction and displacement of interaction centers to the left hemisphere. In boys perceiving verbalized and nonverbalized visual stimuli, a greater contribution of posterocentral cortical areas has been observed. The detected differences are considered to reflect a greater maturity of identification mechanisms in girls aged seven to eight years as compared to boys.     

Age-related specificity of the frontal and temporoparietal cortex activation levels in three-to seven-year-old children

The results of studies on the specificity of formation of the frontal and temporoparietal cortex activation levels in children aged three, four to five, and six to seven years with a normal development of higher mental functions and speech are summarized. The parameters of the stable millivolt-range potential recorded from the head surface were used for this purpose. The results obtained are compared with published data on the specificity of the morphological and functional organization of the brain and the level of development of the slow information control system estimated on the basis of EEG parameters at the same ages. The estimation of the contribution of the brain superslow information control system by one of the basic parameters of state makes it possible to determine, in quantitative terms, (1) the characteristics of the formation of activation levels of cerebral systems involved in the regulation of the resting state, higher mental functions, and speech at different stages of ontogeny; (2) (on the basis of the stable-potential variance) the degrees of freedom of the activation levels of the cerebral systems studied, which determine their regulatory capacity at different ages; and (3) the degree of development of the system-forming mechanisms combining all these systems into an integrated whole at a certain stage of ontogeny (from six to seven years of age).     

Hyponatraemia and death or permanent brain damage in healthy children.

OBJECTIVE--To determine if hyponatraemia causes permanent brain damage in healthy children and, if so, if the disorder is primarily limited to females, as occurs in adults. DESIGN--Prospective clinical case study of 16 affected children and a review of 24,412 consecutive surgical admissions at one medical centre. PATIENTS--16 children (nine male, seven female; age 7 (SD 5) years) with generally minor illness were electively hospitalised for primary care. Consultation was obtained for the combination of respiratory arrest with symptomatic hyponatraemia (serum sodium concentration less than or equal to 128 mmol/l). MAIN OUTCOME MEASURES--Presence, gender distribution, and classification of permanent brain damage in children with symptomatic hyponatraemia in both prospective and retrospective studies. RESULTS--By retrospective evaluation the incidence of postoperative hyponatraemia among 24,412 patients was 0.34% (83 cases) and mortality of those afflicted was 8.4% (seven deaths). In the prospective population the serum sodium concentration on admission was 138 (SD 2) mmol/l. From three to 120 inpatient hours after hypotonic fluid administration patients developed progressive lethargy, headache, nausea, and emesis with an explosive onset of respiratory arrest. At the time serum sodium concentration was 115 (7) mmol/l and arterial oxygen tension 6 (1.5) kPa. The hyponatraemia was primarily caused by extrarenal loss of electrolytes with replacement by hypotonic fluids. All 16 patients had cerebral oedema detected at either radiological or postmortem examination. All 15 patients not treated for their hyponatraemia in a timely manner either died or were permanently incapacitated by brain damage. The only patient treated in a timely manner was alive but mentally retarded. CONCLUSIONS--Symptomatic hyponatraemia can result in high morbidity in children of both genders, which is due in large part to inadequate brain adaptation and lack of timely treatment.     

Age-related,interindividual, and right/left differences in anterior-posterior foot pressure ratio in preschool children

Background

This study aimed to examine age-related, interindividual, and right/left differences in anterior-posterior foot pressure ratio in 764 preschool children (364 boys and 400 girls) aged 3.5-6.5 years.

Methods

Subjects maintained an upright standing posture for 10 seconds on the Footview Clinic, an instrument designed to calculate the anterior-posterior foot pressure ratio. The ratio of anterior foot pressure in each subject’s right and left feet was selected as a variable, and the mean of a 10 s measurement was used for analysis.

Results

The ratio of anterior foot pressure was significantly larger in the right foot than in the left foot. With regard to age, the ratio of anterior foot pressure was significantly larger in children aged over 4.5 years than in children aged 3.5 years. It was also larger in children aged 6 and 6.5 years than in children aged 4 years. Interindividual differences in variables were large, and coefficients of variance were highest in children aged 3.5 years and lowest in children aged 6.5 years.

Conclusions

In conclusion, anterior foot pressure increases with age in preschool children. Interindividual differences in anterior foot pressure are large and tend to decrease with age. Furthermore, the anterior foot pressure is slightly higher in the right foot than in the left foot. These results will be useful for various studies, such as examining relationships between the anterior-posterior foot pressure ratio and factors, such as untouched toes, physical fitness, and level of exercise.