Higher Responsiveness of Pattern Generation Circuitry to Sensory Stimulation in Healthy Humans Is Associated with a Larger Hoffmann Reflex

Simple Summary Individual differences in the sensorimotor circuitry play an important role for understanding the nature of behavioral variability and developing personalized therapies. While the spinal network likely requires relatively rigid organization, it becomes increasingly evident that adaptability and inter-individual variability in the functioning of the neuronal circuitry is present not only in the brain but also in the spinal cord. In this study we investigated the relationship between the excitability of pattern generation circuitry and segmental reflexes in healthy humans. We found that the high individual responsiveness of pattern generation circuitries to tonic sensory input in both the upper and lower limbs was related to larger H-reflexes. The results provide further evidence for the importance of physiologically relevant assessments of spinal cord neuromodulation and the individual physiological state of reflex pathways. The state and excitability of pattern generators are attracting the increasing interest of neurophysiologists and clinicians for understanding the mechanisms of the rhythmogenesis and neuromodulation of the human spinal cord. It has been previously shown that tonic sensory stimulation can elicit non-voluntary stepping-like movements in non-injured subjects when their limbs were placed in a gravity-neutral unloading apparatus. However, large individual differences in responsiveness to such stimuli were observed, so that the effects of sensory neuromodulation manifest only in some of the subjects. Given that spinal reflexes are an integral part of the neuronal circuitry, here we investigated the extent to which spinal pattern generation excitability in response to the vibrostimulation of muscle proprioceptors can be related to the H-reflex magnitude, in both the lower and upper limbs. For the H-reflex measurements, three conditions were used: stationary limbs, voluntary limb movement and passive limb movement. The results showed that the H-reflex was considerably higher in the group of participants who demonstrated non-voluntary rhythmic responses than it was in the participants who did not demonstrate them. Our findings are consistent with the idea that spinal reflex measurements play important roles in assessing the rhythmogenesis of the spinal cord

Tapping into rhythm generation circuitry in humans during simulated weightlessness conditions

An ability to produce rhythmic activity is ubiquitous for locomotor pattern generation and modulation. The role that the rhythmogenesis capacity of the spinal cord plays in injured populations has become an area of interest and systematic investigation among researchers in recent years, despite its importance being long recognized by neurophysiologists and clinicians. Given that each individual interneuron, as a rule, receives a broad convergence of various supraspinal and sensory inputs and may contribute to a vast repertoire of motor actions, the importance of assessing the functional state of the spinal locomotor circuits becomes increasingly evident. Air-stepping can be used as a unique and important model for investigating human rhythmogenesis since its manifestation is largely facilitated by a reduction of external resistance. This article aims to provide a review on current issues related to the ‘locomotor’ state and interactions between spinal and supraspinal influences on the central pattern generator circuitry in humans, which may be important for developing gait rehabilitation strategies in individuals with spinal cord and brain injuries

Mental and Pedagogical Techniques in Teaching Children with Special Educational Needs: Neuropedagogical Aspect

The relevance of the topic is in characterizing the neuropedagogical aspect of mental and pedagogical techniques in teaching children with special educational needs. The article contains the theoretical analysis of the elaborations on this topic, the definition of the concept «inclusive education», the chief principles of teaching students with limited capabilities; the neuropedagogical aspect of mental and pedagogical techniques in teaching children with special educational needs. The understanding of the concept of inclusive education has been studied, the literary sources on this topic have been summarized. On the basis of the findings it has been concluded that it is essential to critically review traditional approaches in the neuropedagogical aspect of mental and pedagogical techniques in teaching children with special educational needs. The author of the article remarks that in the context of vocational training for teachers' educational activity there might be efficient the techniques of teaching children with special educational needs, contributing to the better integration of children with special educational needs into the educational process. The system forming foundation of the inclusion is the postulate of acknowledging the capabilities of each student. Consequently, educational process must be arranged so that fully reveal the educational needs of each child.</p

Complexity of modular neuromuscular control increases and variability decreases during human locomotor development

When does modular control of locomotion emerge during human development? One view is that modularity is not innate, being learnt over several months of experience. Alternatively, the basic motor modules are present at birth, but are subsequently reconfigured due to changing brain-body-environment interactions. One problem in identifying modular structures in stepping infants is the presence of noise. Here, using both simulated and experimental muscle activity data from stepping neonates, infants, preschoolers, and adults, we dissect the influence of noise, and identify modular structures in all individuals, including neonates. Complexity of modularity increases from the neonatal stage to adulthood at multiple levels of the motor infrastructure, from the intrinsic rhythmicity measured at the level of individual muscles activities, to the level of muscle synergies and of bilateral intermuscular network connectivity. Low complexity and high variability of neuromuscular signals attest neonatal immaturity, but they also involve potential benefits for learning locomotor tasks

Rethinking First Language–Second Language Similarities and Differences in English Proficiency: Insights From the ENglish Reading Online (ENRO) Project

This article presents the ENglish Reading Online (ENRO) project that offers data on English reading and listening comprehension from 7,338 university-level advanced learners and native speakers of English representing 19 countries. The database also includes estimates of reading rate and seven component skills of English, including vocabulary, spelling, and grammar, as well as rich demographic and language background data. We first demonstrate high reliability for ENRO tests and their convergent validity with existing meta-analyses.We then provide a bird’s-eye view of first (L1) and second (L2) language comparisons and examine the relative role of various predictors of reading and listening comprehension and reading speed. Across analyses, we found substantially more overlap than differences between L1 and L2 speakers, suggesting that English reading proficiency is best considered across a continuum of skill, ability, and experiences spanning L1 and L2 speakers alike. We end by providing pointers for how researchers can mine ENRO data for future studies

Canards Oscillations, Noise-Induced Splitting of Cycles and Transition to Chaos in Thermochemical Kinetics

We study how noise generates complex oscillatory regimes in the nonlinear thermochemical kinetics. In this study, the basic mathematical Zeldovich–Semenov model is used as a deterministic skeleton. We investigate the stochastic version of this model that takes into account multiplicative random fluctuations of temperature. In our study, we use direct numerical simulation of stochastic solutions with the subsequent statistical analysis of probability densities and Lyapunov exponents. In the parametric zone of Canard cycles, qualitative effects caused by random noise are identified and investigated. Stochastic P-bifurcations corresponding to noise-induced splitting of Canard oscillations are parametrically described. It is shown that such P-bifurcations are associated with splitting of both amplitudes and frequencies. Studying stochastic D-bifurcations, we localized the rather narrow parameter zone where transitions from order to chaos occur

Muscle Activity during Passive and Active Movements in Preterm and Full-Term Infants

Manifestation of muscle reactions at an early developmental stage may reflect the processes underlying the generation of appropriate muscle tone, which is also an integral part of all movements. In preterm infants, some aspects of muscular development may occur differently than in infants born at term. Here we evaluated early manifestations of muscle tone by measuring muscle responses to passive stretching (StR) and shortening (ShR) in both upper and lower limbs in preterm infants (at the corrected age from 0 weeks to 12 months), and compared them to those reported in our previous study on full-term infants. In a subgroup of participants, we also assessed spontaneous muscle activity during episodes of relatively large limb movements. The results showed very frequent StR and ShR, and also responses in muscles not being primarily stretched/shortened, in both preterm and full-term infants. A reduction of sensorimotor responses to muscle lengthening and shortening with age suggests a reduction in excitability and/or the acquisition of functionally appropriate muscle tone during the first year of life. The alterations of responses during passive and active movements in preterm infants were primarily seen in the early months, perhaps reflecting temporal changes in the excitability of the sensorimotor networks

Интерактивные технологии внедрения олимпийского образования в учебный процесс студентов

Shift of priorities and social values in today's society leads to the need for constant improvement of educational process in higher education institutions. The experts note (Bystrova Yu.V., 2015; Gladush V.A. & Lysenko G.I., 2014; Naul R., Binder D., Ivanenko G., 2019) that the outdated practices prevail in today’s practical activity of higher educational specialized institutions, the ideas of democratization are not sufficiently implemented. The main problems in the development of higher education institutions are student low motivation to acquire knowledge and drop in attendance. This situation necessitates rethinking of the principles, functions and technologies of managing specialist training in Physical Culture and Sports and, thereupon, develops new approaches to the organization of the pedagogical process in a higher education institution. The analysis of special scientific and methodological literature indicates that today the ways of integration of the Olympic education into the school educational process have been extensively revealed (Armor K, Dagkas S., 2012), the educational potential of the Olympic movement has been elucidated (Bulatov M. & Platonov V., 2018), the importance of integrating Olympic education into the specialist training in Physical Culture and Sports (Radchenko LO, 2016), the activity peculiarities of the Olympic Studies Centers operating as part of the specialized higher education institutions of Ukraine (Zagitova & Radchenko, 2019) have been disclosed, whereas the problem of improving the educational process by integrating Olympic education into the educational process of higher education institutions remains a pressing scientific matter. Today’s educational requirements include the training of highly qualified specialists who are able to integrate the theoretical knowledge and practical skills acquired at a higher educational institution into an integral system effectively used in their professional activities. In order to successfully realize personal educational potential of future specialists in Physical Culture and Sports, the development conditions of the qualities such as criticism and non-standard thinking, the ability to produce new ideas and work in a team, etc., must be created. Such tasks are facilitated by the use of interactive learning technologies in the educational process. The working hypothesis is that the use of interactive learning technologies in the study of Olympic education related issues will improve the efficiency of student educational process in higher education institutions preparing future specialists in Physical Culture and Sports

Tonic and Rhythmic Spinal Activity Underlying Locomotion

Ivanenko YP, Gurfinkel VS, Selionov V, et al. Tonic and Rhythmic Spinal Activity Underlying Locomotion. Current Pharmaceutical Design. 2017;23(12):1753-1763

The Structure and Properties of Fe(II) 1,10-Phenanthroline-Thiobarbiturate

Методом РСА определена структура (cif-file CCDC № 1831367) моноядерного комплекса [Fe(Bipy)(H2O)2(Htba)2]∙6H2O (I), где Bipy = 2,2’-дипиридил и Н2tba = 2-тиобарбитуровая кислота. Кристаллы I ромбические: a = 17.4697(7), b = 11.7738(4), c = 13.4314(5) Å, V = 2762.6(2), пр. гр. Pnma, Z = 4. В экваториальной плоскости октаэдрического комплекса расположены два атома азота молекулы Bipy и две молекулы воды, а два S-координированных иона Htba− занимают аксиальные позиции. Структура стабилизирована многочисленными водородными связями N−H∙∙∙O, O−H∙∙∙O, С−H∙∙∙O, C−H∙∙∙S и π–π-взаимодействием между молекулами Bipy и ионами Нtba−. Соединение охарактеризовано методами порошковой рентгенографии, термического анализа и ИК-спектроскопииThe structure of the mononuclear complex [Fe(Bipy)(H2O)2(Htba)2]∙6H2O (I), where Bipy – 2,2’-dipyridine, H2tba – 2-thiobarbituric acid (C4H4N2O2S), was determined by single crystal X-ray diffraction technique (cif-file CCDC No. 1831367). Crystals I are rhombic: a = 17.4697 (7), b = 11.7738 (4), c = 13.4314 (5) Å, V = 2762.6(2) Å3, space group Pnma, Z = 4. Two nitrogen atoms of the Bipy molecule and two water molecules are located in the equatorial plane of the octahedral complex, and two S-coordinated Htba− ions the axial positions are occupied. The structure is stabilized by N−H∙∙∙O, O−H∙∙∙O, С−H∙∙∙O, C−H∙∙∙S intermolecular hydrogen bonds and π–π interaction between Bipy and Htba−. The compound is characterized by the methods of powder X-ray diffraction, thermal analysis, and IR spectroscop