The crucial aspect of this demonstration is the discovery of renewal events, hidden in the computed dynamics of a multifractal metronome, which enables the replacement of the phenomenon of strong ...anticipation with a time delayed cross-correlation between the driven and the driving metronome. We establish that the phenomenon of complexity matching, which is the theme of an increasing number of research groups, has two distinct measures. One measure is the sensitivity of a complex system to environmental multifractality; another is the level of information transfer, between two complex networks at criticality. The cross-correlation function is evaluated in the ergodic long-time limit, but its delayed maximal value is the signature of information transfer occurring in the non ergodic short-time regime. It is shown that a more complex system transfers its multifractality to a less complex system while the reverse case is not possible.
In swimming propelling efficiency is partly determined by intra-cyclic velocity fluctuations. The higher these fluctuations are at a given average swimming velocity, the less efficient is the ...propulsion. This study explored whether the leg-arm coordination (i.e. phase relation ϕ) within the breaststroke cycle can be influenced with acoustic pacing, and whether the so induced changes are accompanied by changes in intra-cyclic velocity fluctuations. Twenty-six participants were asked to couple their propulsive leg and arm movements to a double-tone metronome beat and to keep their average swimming velocity constant over trials. The metronome imposed five different phase relations ϕi (90, 135, 180, 225 and 270°) of leg-arm coordination. Swimmers adjusted their technique under the influence of the metronome, but failed to comply to the velocity requirement for ϕ = 90 and 135°. For imposed ϕ = 180, 225 and 270°, the intra-cyclic velocity fluctuations increased with increasing ϕ, while average swimming velocity did not differ. This suggests that acoustic pacing may be used to adjust ϕ and thereby performance of breaststroke swimming given the dependence of propelling efficiency on ϕ.
Highlights • Skill training and strength training are associated with the same neuroplastic changes in the central nervous system. • Strength training externally paced increases corticospinal ...excitability compared to self-paced strength training. • These findings have theoretical implications for rehabilitation when prescribing motor skill training.
Abstract. Purpose The purpose of this study was to present the effects of Interactive metronome (IM) on timing for children with Attention-Deficit Hyperactivity Disorder (ADHD). Subjects and Methods ...The subjects of the present study were 2 children diagnosed with ADHD. Pre- and post-intervention tests were completed by the researcher using Long Form Assessment (LFA) test of IM and K-WPPSI-IV. The subjects were provided with IM for 40 minutes at a time, 2 times per week, for a total of 8 weeks. Results The timing decreased after IM intervention. The subjects showed improvement in attention span after IM intervention. Working memory index as well as processing speed index were increased after intervention, as shown by the Korean-Wechsler Preschool and Primary Scale of Intelligence-IV (K-WPPSI-IV). Conclusion IM was effective in improving timing, attention, working memory and processing speed in children with ADHD.
Current treatment of retinoblastoma involves using the maximum dose of chemotherapy that induces tumor control and is tolerated by patients. The impact of dose and schedule on the cytotoxicity of ...chemotherapy has not been studied. Our aim was to gain insight into the cytotoxic and antiangiogenic effect of the treatment scheme of chemotherapy used in retinoblastoma by means of different in vitro models and to evaluate potential effects on multi-drug resistance proteins. Two commercial and two patient-derived retinoblastoma cell types and two human vascular endothelial cell types were exposed to increasing concentrations of melphalan or topotecan in a conventional (single exposure) or metronomic (7-day continuous exposure) treatment scheme. The concentration of chemotherapy causing a 50% decrease in cell proliferation (IC50) was determined by MTT and induction of apoptosis was evaluated by flow cytometry. Expression of ABCB1, ABCG2 and ABCC1 after conventional or metronomic treatments was assessed by RT-qPCR. We also evaluated the in vivo response to conventional (0.6 mg/kg once a week for 2 weeks) and metronomic (5 days a week for 2 weeks) topotecan in a retinoblastoma xenograft model. Melphalan and topotecan were cytotoxic to both retinoblastoma and endothelial cells after conventional and metronomic treatments. A significant decrease in the IC50 (median, 13-fold; range: 3-23) was observed following metronomic chemotherapy treatment in retinoblastoma and endothelial cell types compared to conventional treatment (p<0.05). Metronomic topotecan or melphalan significantly inhibited in vitro tube formation in HUVEC and EPC compared to vehicle-treated cells (p<0.05). Both treatment schemes induced apoptosis and/or necrosis in all cell models. No significant difference was observed in the expression of ABCB1, ABCC1 or ABCG2 when comparing cells treated with melphalan or topotecan between treatment schedules at the IC50 or with control cells (p>0.05). In mice, continuous topotecan lead to significantly lower tumor volumes compared to conventional treatment after 14 days of treatment (p<0.05). Continuous exposure to melphalan or topotecan increased the chemosensitivity of retinoblastoma and endothelial cells to both chemotherapy agents with lower IC50 values compared to short-term treatment. These findings were validated in an in vivo model. None of the dosing modalities induced multidrug resistance mechanisms while apoptosis was the mechanism of cell death after both treatment schedules. Metronomic chemotherapy may be a valid option for retinoblastoma treatment allowing reductions of the daily dose.
The need to upgrade infrastructure for cycling has never been greater, yet urban development in North America continues to privilege car usage. Cities are responding by encouraging alternate modes of ...transportation through bike-friendly design and planning, but the politics of approving such initiatives remain contentious, even though evidence reveals bikeable cities are beneficial in a variety of ways. The purpose of this study was to explore cyclists' experiences within a car-centric city. To this end, this study engaged with local cyclists directly to understand how their experiences were influenced by their surroundings. This qualitative analysis is organized around three themes: (1) identity as a cyclist, (2) riding in a car-centric city, and (3) lived experience with "bicycle-friendly" infrastructure. Cyclists' experiences offer direction for further research on the topic of cycling in leisure studies.
Sensorimotor synchronization (SMS), the coordination of body movements with external stimuli (e.g., dancing, clapping along with music, sport activities), increases throughout childhood when assessed ...by finger-tapping (FT) tasks following rhythmic auditory cues using metronomes. However, metronomes may support less rhythmic entrainment than naturalistic auditory cues like music, so they may be less effective in showing developmental improvement. This study investigated the effects of age and sex on SMS comparing metronome versus music stimuli in four auditory FT tasks with regular fast (inter-stimulus interval ISI = 333 ms) and slow tempi (ISI = 1,000 ms). Participants were 305 typically developing children aged 6 to 11 years. We found improvement (lower variability) in performance with increasing age irrespective of the metronome or music FT and sex, particularly between 6 and 9 years, after which performance stabilized. Nonetheless, mostly irrespective of age, performance for music and metronome stimuli showed differences in synchronization accuracy and variability, indicating that the type of rhythmic stimuli affects performance. A developmental effect was also found in inter-tap variability (but not inter-tap accuracy). Overall, developmental effects were more robust in FT variability (motor implementation) although responses to music and metronome stimuli differed in ways that may be relevant to SMS deficits in clinical populations.
The aim of this study was to compare the effects of two 10‐week non‐laboratory‐based running retraining programs on foot kinematics and spatiotemporal parameters in recreational runners. One hundred ...and three recreational runners (30 ± 7.2 years old, 39% females) were randomly assigned to either: a barefoot retraining group (BAR) with 3 sessions/week over 10 weeks, a cadence retraining group (CAD) who increased cadence by 10% again with 3 sessions/week over 10 weeks and a control group (CON) who did not perform any retraining. The footstrike pattern, footstrike angle (FSA), and spatial‐temporal variables at comfortable and high speeds were measured using 2D/3D photogrammetry and a floor‐based photocell system. A 3 × 2 ANOVA was used to compare between the groups and 2 time points. The FSA significantly reduced at the comfortable speed by 5.81° for BAR (p < 0.001; Cohen's d = 0.749) and 4.81° for CAD (p = 0.002; Cohen's d = 0.638), and at high speed by 6.54° for BAR (p < 0.001; Cohen's d = 0.753) and by 4.71° for CAD (p = 0.001; Cohen's d = 0.623). The cadence significantly increased by 2% in the CAD group (p = 0.015; Cohen's d = 0.344) at comfortable speed and the BAR group showed a 1.7% increase at high speed. BAR and CAD retraining programs showed a moderate effect for reducing FSA and rearfoot prevalence, and a small effect for increasing cadence. Both offer low‐cost and feasible tools for gait modification within recreational runners in clinical scenarios.
Mind wandering is a pervasive feature of human cognition often associated with the withdrawal of task-related executive control processes. Here, we explore the possibility that, in tasks requiring ...executive control to sustain consistent responding, moments of mind wandering could be associated with moments of increased behavioral variability. To test this possibility, we developed and administered a novel task (the metronome response task) in which participants were instructed to respond synchronously (via button presses) with the continuous rhythmic presentation of tones. We provide evidence (replicated across 2 independent samples) that response variability during the 5 trials preceding probe-caught reports of mind wandering (tuned-out and zoned-out mind wandering) is significantly greater than during the 5 trials preceding reports of on-task performance. These results suggest that, at least in some tasks, behavioral variability is an online marker of mind wandering.
•Persons with Multiple Sclerosis show worse rhythmic interlimb coordination.•The most stable interlimb antiphase coordination mode is performed at 1.00 Hz.•Walking capacity and interlimb coordination ...are associated in Multiple Sclerosis.•Cognitive function and interlimb coordination are associated in Multiple Sclerosis.•Associations are strongest in the deviant higher and lower metronome rhythms.
Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system with heterogeneous symptoms. Persons with MS (PwMS) show reduced walking capacity with changes in their gait pattern. It is unknown to which extent coordination deficits are present in PwMS, which can be measured by seated lower leg interlimb coordination tasks, and to which extent they are related to motor and cognitive function.
How is the control of interlimb coordination of the lower limbs characterized in PwMS compared to healthy controls (HC) during a seated rhythmical coordination task and what is the relationship between interlimb coordination, motor or cognitive function?
Rhythmical interlimb coordination was assessed during a single session in 38 PwMS and 13 HC, using a seated rhythmical coordination task, comprising of antiphase flexion-extension of the lower limbs, to metronomes at 0.75 Hz, 1.00 Hz, 1.50 Hz. Outcomes were phase coordination index (PCI), movement amplitude and movement frequency. Correlations between interlimb coordination, motor, and cognitive function were examined.
PwMS showed impaired walking capacity but preserved cognitive function. Mixed model analysis revealed a significant effect of group and metronome frequency for PCI, attenuated by the variability in generating knee (antiphase flexion-extension) movements. Movement amplitude was highest at metronome frequency 1.00 Hz. In PwMS significant correlations were found between PCI and cognitive function when performing the task at metronome frequencies 0.75 Hz and 1.50 Hz, as well as motor function at 1.50 Hz.
PwMS had a higher variability in interlimb coordination compared to HC. The most stable interlimb antiphase coordination mode was performed at 1.00 Hz. Significant correlations support the existence of a relationship between information processing speed, as well as walking impairment, with interlimb coordination. While cognitive and motor control are always needed for interlimb coordination movements, associations are strongest in the deviant higher and lower metronome rhythms.
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