Human CSF Movement Influenced by Vascular Low Frequency Oscillations and Respiration

Background: Cerebrospinal fluid movement (CSF) through the pathways within the central nervous system is of high significance for maintaining normal brain health and function. Low frequency hemodynamics and respiration have both been shown to independently drive CSF in humans. Here, we hypothesize that CSF movement may be driven simultaneously (and in synchrony) by both mechanisms and we study their independent and interactive effects on CSF movement using novel neck fMRI scans.Methods: Caudad CSF movement at the fourth ventricle and hemodynamics of the major neck blood vessels (internal carotid arteries and internal jugular veins) were captured from 11 young healthy volunteers using novel neck fMRI scans with simultaneous measurement of respiration. Two distinct models of CSF movement (1. Low-frequency hemodynamics and 2. Respiration) were independently investigated in corresponding frequency ranges. Possible interactions between these mechanisms were also studied using cross-frequency coupling.Results: The results from this study validated that the caudad CSF movement may be driven by both low frequency hemodynamics (0.01 Hz – 0.1 Hz) and respiration (0.2 Hz - 0.4 Hz), through different mechanisms. We show that the dynamics of brain fluids can be assessed from the neck, by studying the interrelationships between major neck blood vessels and the CSF movement at the fourth ventricle. We also demonstrate that there exists a cross-frequency interaction between two separable mechanisms.Conclusions: The human CSF system is capable of responding to multiple interacting physiological forces at the same time. This information may help inform the pathological mechanisms behind CSF movement-related disorders and facilitate new approaches to therapeutic interventions.

Lexical frequency and sentence context influence the brain’s response to single words

Typical adults read remarkably quickly. Such fast reading is facilitated by brain processes that are sensitive to both word frequency and contextual constraints. It is debated as to whether these attributes have additive or interactive effects on language processing in the brain. We investigated this issue by analysing existing magnetoencephalography data from 99 participants reading intact and scrambled sentences. Using a cross-validated model comparison scheme, we found that lexical frequency predicted the word-by-word elicited MEG signal in a widespread cortical network, irrespective of sentential context. In contrast, index (ordinal word position) was more strongly encoded in sentence words, in left front-temporal areas. This confirms that frequency influences word processing independently of predictability, and that contextual constraints affect word-byword brain responses. With a conservative multiple comparisons correction, only the interaction between lexical frequency and surprisal survived, in anterior temporal and frontal cortex, and not between lexical frequency and entropy, nor between lexical frequency and index. However, interestingly, the uncorrected index*frequency interaction revealed an effect in left frontal and temporal cortex that reversed in time and space for intact compared to scrambled sentences. Finally, we provide evidence to suggest that, in sentences, lexical frequency and predictability may independently influence early (<150ms) and late stages of word processing, but also interact during late stages of word processing (>150-250ms), thus helping to converge previous contradictory eye-tracking and electrophysiological literature. Current neuro-cognitive models of reading would benefit from accounting for these differing effects of lexical frequency and predictability on different stages of word processing.

A descriptive and exploratory study of factors contributing to augmented feedback duration in professional Australian football practice

Augmented feedback supplements or replaces task-intrinsic feedback and is common in team sports, however, no studies have reported on augmented feedback provision in professional Australian Football (AF) practice. This study investigated the effects of practice characteristics (feedback intervention frequency, practice time, practice type, season phase, practice activity form and competitive match result) on the duration of feedback provided by professional AF coaches. Two linear mixed-effects models were constructed. The first examined the collective associations between these practice characteristics and feedback durations while the second model investigated the associations between the same practice characteristics and previous match result. Results showed the feedback intervention frequency, practice time and a practice time*feedback intervention frequency interaction explained 65% of feedback duration whenever feedback was provided. Additionally, practice time, feedback intervention frequency, a practice time*match result interaction and a match result*feedback intervention frequency interaction explained 99% of feedback duration in-season. Important factors that were hypothesised to affect feedback durations in AF such as practice type, practice activity form or season phase did not contribute any explanatory power. This study provides information on how professional AF coaches provide augmented feedback in-situ and provides opportunities for skill acquisition specialists to aid coaches when delivering augmented feedback.

Analysis of the Frequency Interaction of the Turbine Block in the Stand for the Magnitude of the Error in Measuring the Turbine’s Power

An algorithm for constructing a dynamic analysis during the formation of a wave field of stand for testing turbines and the effect of the frequency interaction of the stand’s elements on the measurement of its magnitude is described. The research algorithm involves the use of theoretical solutions of nonlinear wave processes using linear oscillations, refined by experiments. The diagnostic model can determine the technical condition of the stand’s elements and also determine the causes of the discrepancies between the calculated and measured turbine power values. To clarify the stiffness coefficients between the stand’s elements, a modal analysis was used to obtain the range of their changes depending on the external dynamic load, which made it possible to assess the impact of changes in the frequency interaction conditions on the turbine power measurement at different test modes. The conditions for amplifying the amplitude of oscillations at their eigenfrequencies are obtained, and the value of the possible deviation of the expected power value at its measurement for specific modes of the turbine is calculated. The algorithm allows to estimate the dynamic state of the stand-in different research modes of turbines and give recommendations for reducing the level of frequency interaction.

Associations among physical activity tracking, physical activity motivation and level of physical activity in young adults

Whether physical activity (PA) tracking devices are associated with PA motivation in young adults is largely unknown. We compared total PA minutes per week, total minutes walking/week, meeting moderate-to vigorous PA guidelines, and past-year activity tracking across motivation cluster profiles among 799 young adults. Participants with “self-determined” profiles reported the highest total PA minutes/week followed by participants with “low intrinsic,” “controlled self-determined,” and “high external” profiles. A behavior regulation profile X activity tracking frequency interaction was not significant. Behavior regulation profiles may need to be considered in PA interventions using activity trackers.

The Application Status and Development Trend of Digital Art Sensory Interaction

with the continuous development of digital media, the high-frequency interaction between people and personal digital devices continues to promote the development of digital entertainment products. At present, digital art has its own development in the interaction of vision, hearing, touch, taste and smell. This article summarizes the application status of sensory interaction, analyzes the future development trend of digital art, and finds out that digital art will develop in the fields of artificial intelligence, sensory equipment and sensor technology iteration in the future through data analysis, literature study and case analysis In this paper, the author come up with some feasible reference for practitioners and researchers in related fields.

Lexical frequency and sentence context influence the brain’s response to single words

Remarkably fast reading is facilitated by brain processes that are sensitive to both word frequency and contextual constraints. It is debated as to whether these attributes have additive or interactive effects on language processing in the brain. We investigated this issue by analysing existing magnetoencephalography data from 99 participants reading sentences and word-lists. Using a cross-validated model comparison scheme, we found that lexical frequency predicted the word-by-word elicited MEG signal in a widespread cortical network, irrespective of sentential context. In contrast, index (ordinal word position) was more strongly encoded in sentence words, in left front-temporal areas. This suggests that frequency influences word processing independently of predictability, and that contextual constraints affect word-by-word brain responses. Interestingly, an exploration of the index*frequency interaction revealed an effect (in left frontal and temporal cortex) that reversed in time and space for sentences compared to word-lists. These findings may improve future neuro-cognitive models of reading.

Subthalamic beta-targeted neurofeedback speeds up movement initiation but increases tremor in Parkinsonian patients

Previous studies have explored neurofeedback training for Parkinsonian patients to suppress beta oscillations in the subthalamic nucleus (STN). However, its impacts on movements and Parkinsonian tremor are unclear. We developed a neurofeedback paradigm targeting STN beta bursts and investigated whether neurofeedback training could improve motor initiation in Parkinson’s disease compared to passive observation. Our task additionally allowed us to test which endogenous changes in oscillatory STN activities are associated with trial-to-trial motor performance. Neurofeedback training reduced beta synchrony and increased gamma activity within the STN, and reduced beta band coupling between the STN and motor cortex. These changes were accompanied by reduced reaction times in subsequently cued movements. However, in Parkinsonian patients with pre-existing symptoms of tremor, successful volitional beta suppression was associated with an amplification of tremor which correlated with theta band activity in STN local field potentials, suggesting an additional cross-frequency interaction between STN beta and theta activities.