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Abrams Geoffrey D - - 2011
The tennis serve has the potential for musculoskeletal injury as it is an overhead motion and is performed repetitively during play. Early studies evaluating the biomechanics and injury potential of the tennis serve utilized skin-based marker technologies; however, markerless motion measurement systems have recently become available and have obviated some ...
Torres Elizabeth B EB Psychology Department (Busch Campus), Rutgers University, 152 Frelinghuysen Rd, Piscataway, NJ 08854, USA. - - 2011
This work investigated whether fundamental differences emerged between segments of complex movement sequences performed at different instructed speeds. To this end, we tested 5 novices and 1 karate expert as they performed beginner's martial arts routines. We found that if one blindly took these segments and separated them according to ...
Adam Robert R a Institute of Cognitive Neuroscience, University College London , London , - - 2012
Impulsivity is often characterized by rapid decisions under risk, but most current tests of decision-making do not impose time pressures on participants' choices. Here we introduce a new traffic lights test which requires people to choose whether to program a risky, early eye movement before a traffic light turns green ...
Kayaert Greet - - 2011
In recent studies, researchers have discovered a larger neural activation for stimuli that are more extreme exemplars of their stimulus class, compared with stimuli that are more prototypical. This has been shown for faces as well as for familiar and novel shape classes. We used a visual search task to ...
Estis Julie M - - 2011
Speech intelligibility performance with an in-the-ear microphone embedded in a custom-molded deep-insertion earplug was compared with results obtained using a free-field microphone. Intelligibility differences between microphones were further analyzed to assess whether reduced intelligibility was specific to certain sound classes. 36 participants completed the Modified Rhyme Test using recordings made ...
Ren Yu K - - 2011
Electrorotation (ER) experiments of gold-coated micrometer-sized spheres suspended in an electrolyte are presented for three different ionic conductivities over the frequency range of 100 Hz to 40 MHz. The direction of rotation was observed to be counter-field (opposite to the rotating field vector) with a single rotation peak. The maximum ...
Mather George - - 2012
When creating an artwork, the artist makes a decision regarding the orientation at which the work is to be hung based on their aesthetic judgement and the message conveyed by the piece. Is the impact or aesthetic appeal of a work diminished when it is hung at an incorrect orientation? ...
Vaziri-Pashkam Maryam - - 2011
When a brief flash is presented at the same location as a moving object, the flash is perceived to lag behind the moving object to an extent that increases with the speed of the object. Previous studies showed that moving objects appear faster at low luminance as a result of ...
Hydén Lars-Christer - - 2011
In later stages of Alzheimer's disease many people will engage in noise-making (screaming and other kinds of sounds), often experienced as interruptive by others. A problem with the noise-making is the difficulty in understanding the meaning of the noise. This study addresses two questions: to what extent is noise-making responsive ...
Logvinenko Alexander D - - 2011
It is widely believed that color can be decomposed into a small number of component colors. Particularly, each hue can be described as a combination of a restricted set of component hues. Methods, such as color naming and hue scaling, aim at describing color in terms of the relative amount ...
Burgess Jonathan G - - 2010
Local field potential (LFP) and Electromyographic (EMG) signals were recorded from 12 Parkinsonian patients with tremor-dominant symptoms as they performed passive and voluntary movements. The LFP signals were categorised into episodes of tremorous and atremorous activity (identified through EMG power spectra), then divided into delta (2-4 Hz), theta (4-8 Hz), ...
Gil E - - 2010
In this paper we assessed the possibility of using the pulse rate variability (PRV) extracted from the photoplethysmography signal as an alternative measurement of the HRV signal in non-stationary conditions. The study is based on analysis of the changes observed during a tilt table test in the heart rate modulation ...
Javed Faizan - - 2010
This study investigates the peripheral circulatory and autonomic response to volume withdrawal in haemodialysis based on spectral analysis of photoplethysmographic waveform variability (PPGV). Frequency spectrum analysis was performed on the baseline and pulse amplitude variabilities of the finger infrared photoplethysmographic (PPG) waveform and on heart rate variability extracted from the ...
Ide Satoshi - - 2010
Deep tremor in subduction zones is thought to be caused by small repeating shear slip events on the plate interface with significant slow components. It occurs at a depth of about 30 kilometres and provides valuable information on deep plate motion and shallow stress accumulation on the fault plane of ...
Mizuno Masaki - - 2010
We estimated the transfer function of autonomic heart rate (HR) control by using random binary sympathetic or vagal nerve stimulation in anaesthetized rats. The transfer function from sympathetic stimulation to HR response approximated a second-order, low-pass filter with a lag time (gain, 4.29 +/- 1.55 beats min(1) Hz(1); natural frequency, ...
Antelmi Ivana - - 2010
BACKGROUND: The relation between left ventricular filing velocities determined by Doppler echocardiography and autonomic nervous system function assessed by heart rate variability (HRV) is unclear. The aim of this study was to evaluate the influence of the autonomic nervous system assessed by the time and frequency domain indices of HRV ...
Larsen P D - - 2010
Respiratory sinus arrhythmia (RSA) is the beat-to-beat fluctuation in heart rate at the frequency of the respiratory cycle. While it is common to study RSA under conditions of controlled breathing, where respiratory frequency, and sometimes tidal volume and inspiratory:expiratory ratio are controlled, the effect of controlled breathing on RSA is ...
Legros A - - 2010
Human physiological tremor is a complex phenomenon that is modulated by numerous mechanical, neurophysiological, and environmental conditions. Researchers investigating tremor have suggested that acute hypoxia increases tremor amplitude. Based on the results of prior studies, we hypothesized that human participants exposed to a simulated altitude of 4,500 m would display ...
Orini Michele - - 2010
Interest in therapeutic applications of music has recently increased, as well as the effort to understand the relationship between music features and physiological patterns. In this study, we present a methodology for characterizing music-induced effects on the dynamics of the heart rate modulation. It consists of three steps: (i) the ...
Weippert Matthias - - 2010
The first aim of this study was to compare an ambulatory five-lead ECG system with the commercially available breast belt measuring devices; Polar S810i and Suunto t6, in terms of R-R interval measures and heart rate variability (HRV) indices. The second aim was to compare different HRV spectral analysis methods. ...
Maeda Kazuo - - 2010
AIMS: To determine the loss of fetal heart rate (FHR) baseline variability by frequency analysis. METHODS: The FHR tracings of 12 normal fetuses and others with various conditions, as well as flat FHR tracings of a late deceleration (LD) and anencephaly recorded with Doppler fetal monitors, were scanned and processed ...
Cennini Giovanni - - 2010
In this paper, we present a novel photoplethysmographic device that operates remotely, i.e. not in contact with the skin. The device allows for real time measurements of heart rate with motion artifact reduction from a distance of a few centimeters up to several meters. High mobility of users is achieved ...
Daneault Jean-Fran?ois - - 2010
OBJECTIVE: Verify whether a unilateral physiological tremor modulation attempt has a bilateral effect on central oscillators responsible for physiological tremor. METHODS: Bilateral finger physiological tremor was recorded in 35 right-handed participants with laser displacement sensors in: (A) control condition, (B) modulation attempt of physiological tremor of the right index finger, ...
La Fountaine M F - - 2010
Heart rate variability (HRV) from the frequency domain and three calculations of entropy (En), approximate (ApEn), sample (SampEn) and Lempel-Ziv (LZEn), were assessed for intra- and inter-visit reproducibility from short-term recordings in persons with tetraplegia and neurologically intact controls. The intraclass correlation coefficient (ICC) was calculated for multiple comparisons to ...
Duman L - - 2010
AIM: Evaluations of sacs and cremaster muscles associated with undescended testis (UT) have revealed a decrease in sympathetic, but an increase in parasympathetic tonuses. Since the low frequency/high frequency power ratio obtained through spectral analysis of heart rate variability (HRV) determines the sympatho-parasympathetic balance, the sympatho-parasympathetic balance as defined by ...
Rocon E E Bioengineering Group, CSIC, Madrid, Spain. - - 2010
Tremor constitutes the most common movement disorder; in fact 14.5% of population between 50 to 89 years old suffers from it. Moreover, 65% of patients with upper limb tremor report disability when performing their activities of daily living (ADL). Unfortunately, 25% of patients do not respond to drugs or neurosurgery. ...
Lee Ming-Yuan MY Department of Electrical Engineering, National Chung Cheng University, Taiwan. - - 2010
Heart Rate variability (HRV) is important in characterizing heart functions. However, artifacts and trends are regularly observed to contaminate the HRV sequences. This study proposes a simple and effective preprocessor for the removal of artifacts and trend in the HRV sequences. A thresholding filter is applied to remove artifacts to ...
Lee Qim Y QY Biomedical Systems Laboratory, School of Electrical Engineering and Telecommunications, the University of New South Wales, Sydney, 2052, - - 2010
Low systemic vascular resistance (SVR) can be a useful indicator for early diagnosis of critical pathophysiological conditions such as sepsis, and the ability to identify low SVR from simple and noninvasive physiological signals is of immense clinical value. In this study, an SVR classification system is presented to recognize the ...
Chang Chi-Sen - - 2010
Electrical stimulation of St. 36 (Zusanli) has been shown to enhance the regularity of gastric myoelectrical activity in healthy subjects. However, the underlying mechanism by which acupuncture alters gastric myoelectrical activity is still not clear. To elucidate the possible role of the autonomic nervous system in mediating the effect of ...
Lu Hanzhang H Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, 75390, USA. - - 2010
The power of fMRI in assessing neural activities is hampered by inter-subject variations in basal physiologic parameters, which may not be related to neural activation but has a modulatory effect on fMRI signals. Therefore, normalization of fMRI signals with these parameters is useful in reducing variations and improving sensitivity of ...
Nigro Gerardo - - 2010
INTRODUCTION: Our study was designed to analyze dynamic changes in autonomic tone before the onset of typical sustained atrioventricular nodal reentry tachycardia (AVNRT) in a large group of patients without structural heart disease. MATERIALS AND METHODS: Twenty-four-hour Holter tapes from 42 consecutive patients (27 men and 15 women; aged 30 ...
Shah R - - 2010
Heart rate variability is a common feature of the vertebrate cardiovascular system and is a consequence of variable input from the sympathetic and parasympathetic branches of the autonomic nervous system. The aim of this study was to examine the role of the autonomic nervous system in regulating heart rate and ...
Gil Eduardo E Communications Technology Group, Aragóln Institute of Engineering Research, University of Zaragoza, Spain. - - 2010
In this work we assessed the possibility of using the pulse rate variability (PRV) extracted from photoplethysmography signal as an alternative measurement of the HRV signal in non-stationary conditions. The study is based on the analysis of the changes observed during tilt table test in the heart rate modulation of ...
Li Cheng C Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, - - 2010
We propose a new band-phase-randomized surrogate data method to evaluate the chaotic dynamics in the high (HF) and low frequency (LF) bands of heart rate variability (HRV) in healthy subjects. The chaotic strength of normal HRV as assessed by a noise titration assay completely vanished when its power spectrum was ...
H?roux M E - - 2010
OBJECTIVES: Quantify the effect of increasing contraction intensity on the amplitude of force fluctuations and neuromuscular and force tremor spectral power. METHODS: Twenty-one subjects with essential tremor (ET) and 22 healthy controls applied isometric wrist extension contractions. Various sub-maximal contraction intensities were evaluated (5%-, 10%-, 20%- and 30%-MVC). Force fluctuations ...
Carignan Benoit B Département de Kinanthropologie, Université du Québec à Montréal, 1205, rue St-Denis, Montreal, QC H3C 3P8, - - 2010
The objective of this study was to determine the importance of every frequency component on total physiological tremor (PT) amplitude. We suspect that since high frequencies of PT are of lower amplitude in displacement, removing them will have little to no impact on PT amplitude. PT of the index finger ...
van Laar J O E H - - 2010
OBJECTIVE: Spectral analysis of heart-rate variability is used to monitor autonomic nervous system fluctuations. The low-frequency component is associated with sympathetic and parasympathetic modulation and the high-frequency component is associated with parasympathetic modulation. The objective was to study whether changes in low-frequency or high-frequency power of heart-rate variability occur in ...
Butz M - - 2010
AIM: Manifest hepatic encephalopathy (HE) goes along with motor symptoms such as ataxia, mini-asterixis, and asterixis. The relevance of motor impairments in cirrhotics without and with minimal HE (mHE) is still a matter of debate. PATIENTS AND METHODS: We tested three different groups of patients with liver cirrhosis: no signs ...
Mainardi Luca - - 2009
Atrial fibrillation (AF) is a common arrhythmia characterized by irregular ventricular response. During AF, beat-to-beat variability of arterial pressure (AP) is increased because of continuous changes in filling time, stroke volume and contractility. Only a few studies have analyzed short-term AP variability during AF but they were mainly focused on ...
Latt Win Tun - - 2009
Active physiological tremor compensation instruments have been under research and development recently. The sensing unit of the instruments provides information on three degrees-of-freedom (DOF) motion of the instrument tip using accelerations provided by accelerometers placed inside the instruments. A complete vector of angular acceleration of the instrument needs to be ...
Buchner Anna M - - 2010
Adenoma detection rates might be improved through use of high-definition colonoscopy, which can detect subtle mucosal changes. We investigated whether the use of high-definition white-light (HDWL) colonoscopy resulted in a higher rate of adenoma detection than standard-definition white-light (SDWL) colonoscopy in a clinical practice setting. This retrospective study included 2430 ...
McNamee David A - - 2010
PURPOSE: Previously published literature has suggested an effect of extremely low-frequency (ELF) magnetic fields (MF) on human heart rate (HR) and heart rate variability (HRV). The combined response of the microcirculation and macrocirculation to ELF MF exposure has not previously been studied in humans. This study investigated the effects of ...
Cervantes Bl?squez Julio C?sar - - 2009
The aim of this study was to test the utility of heart-rate variability (HRV) analyses as a noninvasive means of quantifying cardiac autonomic regulation during precompetitive anxiety situations in swimmers. Psychophysiological state evaluation of 10 volunteer <<master>> swimmers (6 women and 4 men) was obtained by comparing baseline training condition ...
Costa Gabriel Brizuela - - 2009
This study, with a top T-52 class athlete, determines the relationship between stroke frequency (SF) and push time (PT) and wheelchair velocity (Wv) using different handrim diameters (HD) and the effect of different HDs on the athlete's heart rate (HR) and blood lactate (LACT) at competition speeds. Wv shows a ...
Shao Jun J Shanghai Eye, Ear, Nose and Throat Hospital of Fudan University, Shanghai, - - 2010
Acoustic analysis may provide a useful means to quantitatively characterize the tremulous voice. Signals were obtained from 25 subjects with diagnoses of either Parkinson's disease or vocal polyps exhibiting vocal tremor. These were compared to signals from 24 subjects with normal voices. Signals were analyzed via correlation dimension and several ...
Raethjen Jan - - 2009
OBJECTIVE: It has been hypothesized that the basic and first harmonic frequency of Parkinsonian tremor are somewhat independent oscillations the biological basis of which remains unclear. METHODS: We recorded 64-channel EEG in parallel with EMG of the forearm muscles most affected by rest tremor in 21 PD patients. EMG power ...
Lu Guohua - - 2009
Measuring heart rate variability (HRV) is widely used to assess autonomic nervous system function. It requires accurate measurement of the interval between successive heartbeats. This can be achieved from recording the electrocardiogram (ECG), which is non-invasive and widely available. However, methodological problems inherent in recording and analyzing ECG traces have ...
Christakos C N - - 2009
Muscle tremors reflect rhythmical motor unit (MU) activities. Therefore, the MU firing patterns and synchrony determine the properties of the parkinsonian force tremor (FT) and the neurogenic components of associated limb tremors. They may also be indicative of the neural mechanisms of tremor genesis which to date remain uncertain. We ...
Balconi Michela - - 2009
The present study explored the effect of the subjective evaluation and the individual differences related to BIS and BAS (Behavioural Inhibition and Activation System) on autonomic measures and brain oscillations, in response to appetitive and aversive emotional stimuli. Multiple measures were recorded, such as psychophysiological (skin conductance response, heart rate, ...
Peressutti Caroline - - 2010
The dynamic interactions among physiological rhythms imbedded in the heart rate signal can give valuable insights into autonomic modulation in conditions of reduced outward attention. Therefore, in this study we analyzed the heart rate variability (HRV) in different levels of practice in Zen meditation (Zazen). Nineteen subjects with variable experience ...
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