Tapping Rate Research Articles

How do visual, auditory and motor dual-tasking each affect swallowing and chewing function?

It can be challenging to perform a second task at the same time as swallowing. The study aimed to investigate the effect of visual, auditory and motor dual-tasking on swallowing and chewing function in healthy young adults. Right-handed healthy adults without any psychological and cognitive problems were included in the study. Swallowing was evaluated based on the dysphagia limit in different liquid textures such as water and nectar consistencies, and chewing was evaluated by the Test of Masticating and Swallowing Solids. For the second task, visual and auditory performance was assessed using reaction time, and the motor performance was assessed using a bilateral tapping task. Assessments were performed in two steps: baseline and dual-task. For baseline, all evaluation methods were applied individually. After completing the baseline assessment, dual-task assessment were carried out the following day. For dual-task assessment, the swallowing and chewing tasks were performed simultaneously with visual, auditory and motor tasks. Results showed a significant decrease in dysphagia limit in the nectar consistency, and significant increase in chewing time, visual reaction time and tapping rate (right-left) when compared to baseline and dual-task conditions (χ2(3) = 9.61, p = .02; χ2(3) = 9.02, p = .02; χ2(3) = 28.09, p < .001; χ2(3) = 28.97, p < .001; χ2(3) = 21.56, p < .001, respectively). However, there were no differences in dysphagia limit in the water and auditory reaction time compared to baseline and dual-task conditions (χ2(3) = 3.18, p = .36; χ2(3) = 2.56, p = .50, respectively). Results shedding light on how simultaneous dual tasks can influence swallowing and chewing. Dual-tasking cause a decrease in both swallowing/chewing and the visual/motor performances. These results may provide valuable information for designing interventions or strategies aimed at improving or maintaining optimal swallowing and chewing during in various populations during daily life.

Physical property comparison of polymeric KCl sludge composition and polyamine at different temperatures

Drilling mud is a fluid used to assist the drilling process. The composition and physical properties of the mud greatly influence a drilling operation. Drilling operations that penetrate formations with shale content have the potential to experience drilling problems related to shale hydration. To get a good ability to prevent shale hydration, mud is added with polymeric and polyamine KCl additives (shale inhibitors) with the aim of stabilizing shale in contact with drilling fluid, as well as preventing drill cuttings from forming colloids. The results obtained in the KCl polymer mud composition at temperatures of 80°F, 250°F, and 300°F for mud weight were 9.3 ppg, 9.1 ppg, and 9 ppg, respectively. Funnel viscosity was 40 sec/qt, 36 sec/qt, and 34 sec/qt. Tap rates were 4.8 cc, 6 cc, and 6.6 cc. Mud cake remained at 1 mm and pH also remained at 9. While the results obtained on polyamine mud composition at temperatures of 80°F, 250°F, and 300°F for mud weight were 9.2 ppg, 8.9 ppg, and 8.8 ppg, respectively. Funnel viscosity was 26 sec/qt, 20 sec/qt, and 17 sec/qt. Tap rate of 10 cc, 13.8 cc, and 15 cc. Mud cake of 1 mm, 2 mm, and 2 mm. pH remains at 9. The data obtained shows that the results of the physical properties of polymeric KCl mud are better than polyamine mud.

Tap dancing frogs: Posterior toe tapping and feeding in Dendrobates tinctorius

AbstractAnimals have myriad adaptations to help them hunt and feed in the most efficient and effective manner. One mysterious behavior related to hunting and feeding is the posterior toe tapping behavior of some frogs. Biologists and hobbyists alike have long noticed this behavior, but there is little empirical data to explain its causes and consequences. To test the hypothesis that tapping is related to feeding and modulated by environmental context, we conducted a series of related experiments in the Dyeing poison frog, Dendrobates tinctorius. We first confirmed that tap rate was higher during feeding as has been observed in other species. Interestingly, this effect was heightened in the presence of a conspecific. We next asked whether frogs tapped less under conditions when prey were visible, but inaccessible. Finally, we asked whether D. tinctorius adjusted tap rate based on substrate characteristics and whether prey capture success was higher when tapping. In addition to confirming an association between tapping and feeding, our work demonstrates modulation of toe tapping based on social context, prey accessibility, and substrate characteristics. Based on our findings, we suggest that tapping could act to induce prey movement and thereby facilitate prey detection and capture by frogs.

Cardiac Dynamics in Auditory-Motor Synchronization: Roles of Short-Term Training and Rhythm Complexity

ABSTRACT Previous findings suggest that long-term musical training and rhythm complexity may affect performers’ auditory-motor synchrony and their cardiac rhythms. We investigated the effects of short-term training and rhythm complexity on auditory-motor synchronization and cardiac activity as individuals synchronized with auditory rhythms. Forty-two adult participants synchronized their taps with sounded rhythms to form a 2:3 duration ratio (stimulus duration:tap duration) or a 3:2 duration ratio (tap rate held constant across rhythms). Participants received short training with one rhythm and received longer training with the other rhythm. Then, participants completed five experimental trials in which they synchronized their sounded taps with the stimulus rhythm. Cardiac activity was recorded during synchronization. Tapping synchronization was less accurate and more variable for the 3:2 rhythm than the 2:3 rhythm. Linear measures of cardiac activity showed less high-frequency variability during the 3:2 rhythm than the 2:3 rhythm. Behavioral-cardiac correspondences emerged with training: Poorer synchronization was associated with more variable cardiac activity after long training, but not after short training. Finally, there were consistent individual differences in cardiac recurrence and predictability across training conditions. These findings demonstrate both short-term learning effects and rhythm complexity effects on cardiac dynamics during auditory-motor synchronization.

Ultrafast Synthesis of Large‐Sized and Conductive Na3V2(PO4)2F3 Simultaneously Approaches High Tap Density, Rate and Cycling Capability

AbstractThe Na3V2(PO4)2F3 (NVPF) cathode material is usually nano‐sized particles exhibiting low tap density, high specific surface area, correspondingly low volume energy density, and cycle stability of the sodium‐ion batteries (SIBs). Herein, a high‐temperature shock (HTS) strategy is proposed to synthesize NVPF (HTS‐NVPF) with uniform conducting network and high tap density. During a typical HTS process (heating rate of 1100 °C s−1 for 10 s), the precursors rapidly crystallize and form large‐sized and dense particles. The tight connection between particles not only enhances their contact with carbon layers, but also reduces the specific surface area that inhibits side reactions between the interfaces and the electrolyte. Besides, ultrafast synthesis of NVPF reduces the F loss and amount of Na3V2(PO4)3 impurities, which improve cycling capability. The HTS‐NVPF demonstrates a high energy density of 413.4 Wh kg−1 and an ultra‐high specific capacity of 103.4 mAh g−1 at 10 C as well as 84.2% capacity retention after 1000 cycles. In addition, the excellent temperature adaptability of HTS‐NVPF (−45–55 °C) and remarkable electrochemical properties of NVPF||HC full cell demonstrate extreme competitiveness in commercial SIBs. Therefore, the HTS technique is considered to be a high‐efficiency strategy to synthetize NVPF and is expected to prepare other cathode materials.

A common timing mechanism across different millisecond domains: evidence from perceptual and motor tasks

Temporal information processing (TIP) constitutes a complex construct that underlies many cognitive functions and operates in a few hierarchically ordered time domains. This study aimed to verify the relationship between the tens of milliseconds and hundreds of milliseconds domains, referring to perceptual and motor timing, respectively. Sixty four young healthy individuals participated in this study. They underwent two auditory temporal order judgement tasks to assess their performance in the tens of milliseconds domain; on this basis, groups of high-level performers (HLP) and low-level performers (LLP) were identified. Then, a maximum tapping task was used to evaluate performance in the hundreds of milliseconds domain. The most remarkable result was that HLP achieved a faster tapping rate and synchronised quicker with their “internal clock” during the tapping task than did LLP. This result shows that there is a relationship between accuracy in judging temporally asynchronous stimuli and ability to achieve and maintain the pace of a movement adequate to one’s internal pacemaker. This could indicate the strong contribution of a common timing mechanism, responsible for temporal organisation and coordination of behaviours across different millisecond domains.

A study on the correlations between acoustic speech variables and bradykinesia in advanced Parkinson's disease.

Very few studies have assessed the presence of a possible correlation between speech variables and limb bradykinesia in patients with Parkinson's disease (PD). The objective of this study was to find correlations between different speech variables and upper extremity bradykinesia under different medication conditions in advanced PD patients. Retrospective data were collected from a cohort of advanced PD patients before and after an acute levodopa challenge. Each patient was assessed with a perceptual-acoustic analysis of speech, which included several quantitative parameters [i.e., maximum phonation time (MPT) and intensity (dB)]; the Unified Parkinson's Disease Rating Scale (UPDRS) (total scores, subscores, and items); and a timed test (a tapping test for 20 s) to quantify upper extremity bradykinesia. Pearson's correlation coefficient was applied to find correlations between the different speech variables and the tapping rate. A total of 53 PD patients [men: 34; disease duration: 10.66 (SD 4.37) years; age at PD onset: 49.81 years (SD 6.12)] were included. Levodopa intake increased the MPT of sustained phonation (p < 0.01), but it reduced the speech rate (p = 0.05). In the defined-OFF condition, MPT of sustained phonation positively correlated with both bilateral mean (p = 0.044, r-value:0.299) and left (p = 0.033, r-value:0.314) tapping. In the defined-ON condition, the MPT correlated positively with bilateral mean tapping (p = 0.003), left tapping (p = 0.003), and right tapping (p = 0.008). This study confirms the presence of correlations between speech acoustic variables and upper extremity bradykinesia in advanced PD patients. These findings suggest common pathophysiological mechanisms.

Gating at cortical level contributes to auditory-motor synchronization during repetitive finger tapping.

Sensory integration contributes to temporal coordination of the movement with external rhythms. How the information flowing of sensory inputs is regulated with increasing tapping rates and its function remains unknown. Here, somatosensory evoked potentials to ulnar nerve stimulation were recorded during auditory-cued repetitive right-index finger tapping at 0.5, 1, 2, 3, and 4Hz in 13 healthy subjects. We found that sensory inputs were suppressed at subcortical level (represented by P14) and primary somatosensory cortex (S1, represented by N20/P25) during repetitive tapping. This suppression was decreased in S1 but not in subcortical level during fast repetitive tapping (2, 3, and 4Hz) compared with slow repetitive tapping (0.5 and 1Hz). Furthermore, we assessed the ability to analyze temporal information in S1 by measuring the somatosensory temporal discrimination threshold (STDT). STDT increased during fast repetitive tapping compared with slow repetitive tapping, which was negatively correlated with the task performance of phase shift and positively correlated with the peak-to-peak amplitude (% of resting) in S1 but not in subcortical level. These novel findings indicate that the increased sensory input (lower sensory gating) in S1 may lead to greater temporal uncertainty for sensorimotor integration dereasing the performance of repetitive movement during increasing tapping rates.

Reliable estimation of internal oscillator properties from a novel, fast-paced tapping paradigm

Rhythmic structure in speech, music, and other auditory signals helps us track, anticipate, and understand the sounds in our environment. The dynamic attending framework proposes that biological systems possess internal rhythms, generated via oscillatory mechanisms, that synchronize with (entrain to) rhythms in the external world. Here, we focused on two properties of internal oscillators: preferred rate, the default rate of an oscillator in the absence of any input, and flexibility, the oscillator’s ability to adapt to changes in external rhythmic context. We aimed to develop methods that can reliably estimate preferred rate and flexibility on an individual basis. The experiment was a synchronization—continuation finger tapping paradigm with a unique design: the stimulus rates were finely sampled over a wide range of rates and were presented only once. Individuals tapped their finger to 5-event isochronous stimulus sequences and continued the rhythm at the same pace. Preferred rate was estimated by assessing the best-performance conditions where the difference between the stimulus rate and continuation tapping rate (tempo-matching error) was minimum. The results revealed harmonically related, multiple preferred rates for each individual. We maximized the differences in stimulus rate between consecutive trials to challenge individuals’ flexibility, which was then estimated by how much tempo-matching errors in synchronization tapping increase with this manipulation. Both measures showed test–retest reliability. The findings demonstrate the influence of properties of the auditory context on rhythmic entrainment, and have implications for development of methods that can improve attentional synchronization and hearing.

Effect of Early Upward Tapping on Rubber Productivity of Clone PB 260 of the High Metabolic Activity Class

In order to evaluate the effect of early upward tapping on rubber productivity of rubber trees and to determine its proportion relative to downward tapping, a study was conducted at SAPH Divo on the PB 260 clone of the fast metabolic activity class. The experimental set-up was a Fisher block with seven treatments and three replications. Tapping was carried out in d3 with 6 stimulations. Three upward tapping times at 6, 7 and 8 years, each coupled with two concentrations of the stimulating paste 2.5 and 5% of Ethephon and a downwardly tapped control stimulated with 5% of Ethephon were tested. The data collected were for rubber production, isodiametric growth, tapping panel dryness susceptibility and tree physiological profile. The results showed that the different treatments tapped in upward at 6, 7 and 8 years of age significantly improved the productivity of the PB 260 clone relative to the control by downward for nine years. All treatments combined, rubber productivity (4723 kg.ha-1.yr-1) and radial vegetative growth (3.8 cm.yr-1) were good. The gain in rubber productivity of the early upward tapping compared to the downward tapping was 42%. The tapping panel dryness rate was low at 2.6% and the physiological profile of the trees was well balanced. Our results suggest that PB 260, and therefore metabolically active clones, can be tapped in early upward tapping, especially at 6 years of age.

Changes in thumb tapping rates and central motor conduction times are associated in persons with multiple sclerosis

IntroductionIn persons with multiple sclerosis, nerve conductivity can be reduced. The assessment is generally performed via motor evoked potentials (MEP). So far, a strongly associated motor performance surrogate for changes in the extracted central motor conduction time (CMCT) is missing.MethodsCMCT and performance in the nine-hole peg test and maximum thumb tapping frequencies over 10 s of 12 persons with multiple sclerosis were measured prior to and after training over 5 consecutive days. Each training consisted of 10,000 thumb taps at maximum effort with the dominant upper limb.ResultsThe dominant upper limb improved in maximum tapping frequency over 10 s (d = 0.79) and 10,000 taps (d = 1.04), the nine-hole peg test (d = 0.60), and CMCT (d = 0.52). The nondominant upper limb only improved in the nine-hole peg test (d = 0.38). Models of multiple linear regression predicted 0.78 (model 1, tapping performance as factors) and 0.87 (model 2, patient baseline characteristics as factors) of the variance in CMCT changes.DiscussionChanges in CMCT were well predictable, although the assessment of those surrogates is either not economic (model 1) or rather describing a potential of change (model 2). However, we were able to show moderate changes in CMCT within 5 days.

Rhythm as an independent determinant of developmental dyslexia.

Temporal accounts of Developmental Dyslexia (DD) postulate that a timing impairment plays an important role in this learning disorder. However, DD has been associated with timing disorders as well as other motor and cognitive dysfunctions. It is still unclear whether nonverbal timing skills per se may be considered as independent determinants of DD. In this study, we investigated the independent contribution of predictive timing to DD above and beyond the motor and cognitive dysfunctions typically associated with this disorder. Twenty-one children with DD (aged 8-12, nine females) and 27 controls (14 females) were evaluated on perceptual timing, finger tapping, fine motor control, as well as attention and executive tasks. Participants were native French speakers from various socioeconomic backgrounds. The performance of children with DD was poorer than that of controls in most of the tasks. Predictors of DD, as identified by logistic regression modeling, were beat perception and precision in tapping to the beat, which are both predictive timing variables, children's tapping rate, and cognitive flexibility. These data support temporal accounts of DD in which predictive timing impairments partially explain the core phonological deficit, independent from general motor and cognitive functioning, making predictive timing a valuable tool for early diagnosis and remediation of DD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Experiments and simulations on a cold-flow blast furnace hearth model

The blast furnace hearth plays an important role in the operational stability and lifetime of the reactor. The quasi-stagnant bed of coke particles termed the deadman undergoes complex interaction with the flowing hot metal, and remains largely ill-understood. In this work, a cold model blast furnace hearth is presented, and studied using both numerical and experimental techniques. Magnetic Particle Tracking (MPT) is used to investigate the individual particle behaviour within the cylindrical, opaque bed. At high liquid holdup, the particle bed was found to alternate between floating and sitting states, following the liquid level during the tapping and filling cycle. This bed motion was found to induce a migration of particles, thereby slowly renewing the deadman. The rate of horizontal migration increases with the vertical bed amplitude, and the renewal of particles is concentrated around the opening of the tap hole. No direct influence of the coke-free space on the tapping rate was found in these experiments. Instead, the disturbance of the packing in front of the tap hole was observed to lead to a higher tapping rate. Additionally, a coupled numerical framework is presented, in which Computational Fluid Dynamics (CFD), the Volume of Fluid (VOF) method and the Discrete Element Method (DEM) are combined. A simulation set-up is presented which closely replicates the experimental conditions. The position and movement of the floating bed are found to be well-predicted by the VOF/CFD-DEM model. Particle trajectories are presented, and migration of particles within the deadman is observed. Alongside the particle motion, the liquid flow pattern during draining of the vessel is visualised. It is concluded that a coke-free space underneath the deadman significantly impacts the shape of the liquid flow pattern, which affects the erosion processes within the blast furnace hearth.

Latex Harvesting Technologies Adapted to Hevea brasiliensis Muell Clones GT 1; RRIC 100 and BPM 24 Arg. (Euphorbiaceae) belonging to the Moderate Metabolism Class in the Socio-economic Context of Côte d'Ivoire

Improving the productivity of rubber trees has always been a major concern for rubber farmers. The majority of growers opt for overexploitation of the trees. This disturbs the physiological balance of the rubber trees, which leads to the recrudescence of tapping panel dryness and rather to a drop in production. To solve this problem, the present study proposes to define a latex harvesting technology (or technologies) for the moderate metabolism clone class that will allow the improvement of plantation yield and the increase of the economic life of the trees. To achieve this, the GT 1, RRIC 100 and BPM 24 clones of the moderate metabolism class were used as plant material. The results showed that the reduction in tapping frequency had no negative effect on the vegetative state of the trees. This reduction was compensated by a high number of annual stimulations, which resulted in high dry rubber production. Analysis of dry rubber production, radial rubber growth and tapping panel dryness rate indicates that the moderate metabolic class clones performed better with the latex harvesting technologies S/2 d3 6d/7 ET2.5% Pa1(1) 6/y; S/2 d4 6d/7 ET2.5% Pa1(1) 6/y and S/2 d5 6d/7 ET2.5% Pa1(1) 1.

P 40. β-γ phase-amplitude coupling during movements in Parkinson's disease

Question. Enhanced phase amplitude coupling (PAC) between β (13–30 Hz) and broadband γ (50–150 Hz) activities has been found in surface EEG recordings from Parkinson patients at rest [1]. However, the dynamics of PAC during voluntary movement and its relationship with motor impairment of Parkinson“s disease (PD) remain unclear. Methods. Experimental design : We recorded 64-channel EEG signals from 19 PD patients and 20 sex- and age-matched healthy controls at rest, during a repetitive pressing task and during repetitive index finger tapping performed at the patients“ own pace and at their fastest pace. Source analysis : We obtained source signals by projecting EEG sensor signals to the individual cortical surfaces. Independent component analysis (ICA) was applied for separating temporally independent subnetworks of each task in each of the 4 brain regions: premotor cortex, primary motor cortex, primary somatosensory cortex and primary somatosensory complex. PAC analysis: Pairwise transient PAC values were calculated among ICA components of each region by zscore-normalized mean vector length [2] in 300ms windows shifted with 50ms time steps in 3s epochs which included an interval of 1s before, and 2s after the onset of the movement. Statistics : We applied a non-parametric three-way ANOVA [3] to test the effects of the disease state, tasks and different brain regions on PAC. For post-hoc testing, a two tailed Wilcoxon ranksum test was used between groups and Wilcoxon signrank test within groups. Results. As expected, maximum tapping rate was lower, and fastest movements were executed more irregularly in patients compared to controls. ANOVA performed on the β-γ PAC values averaged over the entire 3s-epoch revealed an interaction of disease state and tasks ( p < 0.001). Post-hoc testing showed enhanced PAC in patients compared with controls in the resting state ( p = 0.018), in agreement with previous findings, but not in any of the tapping tasks. However, PAC during the pressing task remained elevated in the patients compared to controls ( p = 0.020). Analysis of the temporal dynamics revealed reduction of PAC after the onset of the movement (0–0.25 s) compared with that of the pre-onset period (−0.5 to −0.25 s). The reduction of PAC relative to pre-onset period correlated with the desynchronization in the β power. However, the PAC reduction relative to the resting state was not correlated with the β power reduction. Discussion. Persistence of PAC differences during the pressing task on one hand, and disappearance of PAC differences during the tapping tasks on the other hand, suggest that exaggerated β-broadband γ PAC, as detected in the resting EEG, is not necessarily directly related to impaired motor behavior in PD patients. As our previous findings [1] have shown that abnormal PAC at rest is unrelated to the β band power, partial renormalization of PAC by movement-related β band desynchronization may suggest that mechanisms modulating β activity during movement may selectively affect β activity involved in abnormal coupling.

Relationship between the Intensity of Latex Harvesting and the Tapping Panel Dryness Expression of Clone GT 1 of Hevea brasiliensis Muell Arg in South-East Côte d'Ivoire

Tapping panel dryness is an important limiting factor in rubber productivity of Hevea brasiliensis. In order to assess the sensitivity to this syndrome, the effect of two intensive latex harvesting technologies on moderately metabolized GT1 clone, has been studied in the South-Eastern region of Côte d'Ivoire. The rubber trees were planted according to the experimental mono-tree device, "One tree one plot design" a tree constituting a repetition, and 31 trees per treatment, selected on circumference and health status criteria. The parameters measured were rubber production, circumference increase, physiological profile and tapping panel dryness sensitivity. The results showed that induction of tapping panel dryness in latex harvesting system, S/2 d/3 6d/7 ET 10 % Pa 1 (1) 1/ w) was significantly low (0.18 ± 0,22 %) than that of the control (S d/1 6d/7 unstimulated, 1.43 ± 1.45 %). Productivity of this particular system was also good (62 ± 16.32 g.a-1.s-1) and it especially has less stress that can cause physiological fatigue, or even the notch dry. Otherwise, Rubber production, radial vegetative growth, physiological parameters of the latex and the tapping panel dryness rate were influenced by the two treatments applied to GT 1. In addition, the medium and high sucrose contents (16.5 ± 3.01%) and thiol group (0.51 ± 0.13 mmol.l-1) of the latex in the treatment (S/2 d/3 6d/7 ET 10% Pa 1 (1) 1 / w), were instrumental in the response to this stimulation. The sensitivity to the tapping panel dryness is in very close linear relation with the harvest intensity of the latex to which the GT 1 clone has been subjected. These results corroborate and confirm the moderate sensitivity to the tapping panel dryness of GT 1 clone.

Spontaneous Production Rates in Music and Speech.

Individuals typically produce auditory sequences, such as speech or music, at a consistent spontaneous rate or tempo. We addressed whether spontaneous rates would show patterns of convergence across the domains of music and language production when the same participants spoke sentences and performed melodic phrases on a piano. Although timing plays a critical role in both domains, different communicative and motor constraints apply in each case and so it is not clear whether music and speech would display similar timing mechanisms. We report the results of two experiments in which adult participants produced sequences from memory at a comfortable spontaneous (uncued) rate. In Experiment 1, monolingual pianists in Buffalo, New York engaged in three production tasks: speaking sentences from memory, performing short melodies from memory, and tapping isochronously. In Experiment 2, English-French bilingual pianists in Montréal, Canada produced melodies on a piano as in Experiment 1, and spoke short rhythmically-structured phrases repeatedly. Both experiments led to the same pattern of results. Participants exhibited consistent spontaneous rates within each task. People who produced one spoken phrase rapidly were likely to produce another spoken phrase rapidly. This consistency across stimuli was also found for performance of different musical melodies. In general, spontaneous rates across speech and music tasks were not correlated, whereas rates of tapping and music were correlated. Speech rates (for syllables) were faster than music rates (for tones) and speech showed a smaller range of spontaneous rates across individuals than did music or tapping rates. Taken together, these results suggest that spontaneous rate reflects cumulative influences of endogenous rhythms (in consistent self-generated rates within domain), peripheral motor constraints (in finger movements across tapping and music), and communicative goals based on the cultural transmission of auditory information (slower rates for to-be-synchronized music than for speech).

Tapping into linguistic rhythm

Rhythmic properties of speech and language have been a matter of long-standing debates, with both traditional production and perception studies delivering controversial findings. The present study examines the possibility of investigating linguistic rhythm using movement-based paradigms. Informed by the theory and methods of sensorimotor synchronization, we developed two finger-tapping tasks (synchronization and reproduction), and tested them with English participants. The synchronization task required participants to tap along with the beat of a looped sentence while the reproduction task asked them to tap out the perceived beat patterns after listening to a sentence loop. The results showed that both tasks engaged participants in period tracking of a beat-like structure in the linguistic stimuli, though synchronization did so to a greater extent. Patterns obtained in the reproduction task tended to converge toward participants’ spontaneous tapping rates and showed a degree of regularization. Data collected in the synchronization task displayed a consistent anchoring of taps with the vowel onsets. Overall, synchronization performance with language resembled many well-established findings of sensorimotor synchronization with metronome and music. We conclude that our setting of the sensorimotor synchronization paradigm—finger tapping along with looped spoken phrases—is a valid experimentation tool for studying rhythm perception in language.

GEORGE®: A Pilot Study of a Smartphone Application for Huntington's Disease.

Current Huntington's disease (HD) measures are limited to subjective, episodic assessments conducted in clinic. Smartphones can enable the collection of objective, real-world data but their use has not been extensively evaluated in HD. Develop and evaluate a smartphone application to assess feasibility of use and key features of HD in clinic and at home. We developed GEORGE®, an Android smartphone application for HD which assesses voice, chorea, balance, gait, and finger tapping speed. We then conducted an observational pilot study of individuals with manifest HD, prodromal HD, and without a movement disorder. In clinic, participants performed standard clinical assessments and a battery of active tasks in GEORGE. At home, participants were instructed to complete the activities thrice daily for one month. Sensor data were used to measure chorea, tap rate, and step count. Audio data was not analyzed. Twenty-three participants (8 manifest HD, 5 prodromal HD, 10 controls) enrolled, and all but one completed the study. On average, participants used the application 2.1 times daily. We observed a significant difference in chorea score (HD: 19.5; prodromal HD: 4.5, p = 0.007; controls: 4.3, p = 0.001) and tap rate (HD: 2.5 taps/s; prodromal HD: 8.9 taps/s, p = 0.001; controls: 8.1 taps/s, p = 0.001) between individuals with and without manifest HD. Tap rate correlated strongly with the traditional UHDRS finger tapping score (left hand: r = -0.82, p = 0.022; right hand: r = -0.79, p = 0.03). GEORGE is an acceptable and effective tool to differentiate individuals with and without manifest HD and measure key disease features. Refinement of the application's interface and activities will improve its usability and sensitivity and, ideally, make it useful for clinical care and research.

Effects of Daily Hand Activities on Age-Related Declines of Dynamic Motor Function in Individual Fingers

The present study examined the effects of daily activities of the hands on finger motor function in older adults. Maximum tapping frequency with each finger during single-finger tapping and alternate movements of index-middle, middle-ring, and ring-little finger pairs during double-finger tapping were compared between older adults who used their hands actively in their daily lives and those who did not. The active participants had significantly faster tapping rates for the ring finger in the single-finger tapping and the middle-ring finger pair in the double-finger tapping than did the inactive participants. Thus, daily activity of the hands in older adults could be effective at preventing the loss of dynamic motor function in individual fingers, especially with greater difficulty in movement, resulting from the degeneration with age.