Motion detection
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One of the most widely investigated functions of the brain is vision. Whereas special attention is often paid to motion detection and its modulation by attention, comparatively still little is known about the structural background of this function. We therefore, examined the white matter microstructural background of coherent motion detection. A random-dot kinematogram paradigm was used to measure the sensitivity of healthy individuals׳ to movement coherence. The potential correlation was investigated between the motion detection threshold and the white matter microstructure as measured by high angular resolution diffusion MRI. The Track Based Spatial Statistics method was used to address this correlation and probabilistic tractography to reveal the connection between identified regions. A significant positive correlation was found between the behavioural data and the local fractional anisotropy in the posterior part of the right superior frontal gyrus, the right juxta-cortical superior parietal lobule, the left parietal white matter, the left superior temporal gyrus and the left optic radiation. Probabilistic tractography identified pathways that are highly similar to the segregated attention networks, which have a crucial role in the paradigm. This study draws attention to the structural determinant of a behavioural function.
- MeSH
- anizotropie MeSH
- bílá hmota anatomie a histologie fyziologie MeSH
- diferenční práh fyziologie MeSH
- difuzní magnetická rezonance MeSH
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mozek anatomie a histologie fyziologie MeSH
- nervové dráhy anatomie a histologie fyziologie MeSH
- psychofyzika MeSH
- světelná stimulace MeSH
- teorie detekce signálu fyziologie MeSH
- vnímání pohybu fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Vzhledem k intermitentní a acyklické povaze sportovního výkonu hráčů sportovních her je nezbytné kombinovat analýzy vnějšího a vnitřního zatížení pro dobrou deskripci kondičních nároků utkání na hráče. Cílem studie bylo ověření reliability měření překonané vzdálenosti hráčů během utkání v házené pomocí systému Video Manual Motion Tracker 1.0 (VMMT 1.0). Videozáznam utkání pro následné posuzování překonané vzdálenosti hráček házené byl pořízen na utkání nejvyšší české soutěže dívek (n=14) v házené v kategorii U18. Čtyřicet zaškolených posuzovatelů vyhodnocovalo třikrát opakovaně překonanou vzdálenost hráček během utkání pro posouzení relativní a absolutní reliability a 2 posuzovatelé zaznamenávali překonanou vzdálenost padesáti odlišných úseků herního děje sledovaných hráček pro posouzení objektivity. Pro výpočet systematické chyby jsme použili jednofaktorovou analýzu rozptylu, dále vnitrotřídní koeficient korelace pro hodnocení intra-subjektové reliability, Pearsonův koeficient korelace pro posouzení objektivity měření a hodnoty absolutní reliability (standardní chyba měření a Bland-Altmanovy 95% limity shody). Studie prokázala srovnatelně vysokou reliabilitu měření s ostatními využívanými systémy
Due to intermittent character of performance in games it is important to combine more methods to describe the load of the players. Former research showed the combination of time-motion analysis and heart rate is appropriate. The goal of this study was to evaluate the reliability of the distance covered measurement by Video Manual Motion Tracker 1.0 during handball match. One warm up handball match (14 players) was recorded to time-motion analysis. Forty instructed observers rated the distance covered repeatedly (three times) to relative and absolute reliability assessment. Then two instructed observers rated the distance covered of fifty match sequences to objectivity assessments. One-way ANOVA was used to detect systematic bias. ICC was calculated to determine intra-rater reliability whereas a coefficient of Pearson product moment correlation was used to express objectivity. The magnitude of absolute reliability was expressed by standard error of measurement (SEM) and by Bland and Altman’s 95% limits of agreement of the two repeated measures. The results of the study showed high reliability of measurement in comparison with other systems.
- Klíčová slova
- analýza herního výkonu, zatížení, utkání, házená,
- MeSH
- lidé MeSH
- mladiství MeSH
- software * MeSH
- sporty fyziologie MeSH
- výkonnost * klasifikace MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- ženské pohlaví MeSH
In this analysis, we present results from measurements performed to determine the stability of a hand tracking system and the accuracy of the detected palm and finger's position. Measurements were performed for the evaluation of the sensor for an application in an industrial robot-assisted assembly scenario. Human-robot interaction is a relevant topic in collaborative robotics. Intuitive and straightforward control tools for robot navigation and program flow control are essential for effective utilisation in production scenarios without unnecessary slowdowns caused by the operator. For the hand tracking and gesture-based control, it is necessary to know the sensor's accuracy. For gesture recognition with a moving target, the sensor must provide stable tracking results. This paper evaluates the sensor's real-world performance by measuring the localisation deviations of the hand being tracked as it moves in the workspace.
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
Nestr.
Pokročilé metody kvantitativní analýzy obrazových dat umožňují neinvazivní objektivizaci pohybových poruch. Námi vyvinuté metodiky obrazové analýzy BradykAn a TremAn chceme rozšířit a validovat pro sledování pohybů horní končetiny a pro měření amplitudy a frekvence klidového a akčního třesu. Metody budou použity k detailní analýze pohybových vzorců a k výzkumu mechanismů bradykineze a třesu u Parkinsonovy nemoci (PN) a dalších neurodegenerativních onemocnění. Zároveň chceme prokázat funkční změny mozkové kůry v obraze metody NIRS, založené na detekci změn zpětné emise infračerveného světla, ke kterým dochází podle aktuální koncentrace oxygenovaného a deoxygenovaného hemoglobinu v závislosti na neuronální aktivitě kortexu. Cílem bude prokázat změny aktivace motorického kortexu související s kinematickými parametry pohybu zaznamenanými systémy BradykAn a TremAn.; Advanced methods for image analysis may allow noninvasive objectification of movement disorders. We want to expand and validate the methods of image analysis BradykAn and TremAn that we developed for monitoring movements of the upper limbs and for measuring the amplitude and frequency of resting and action tremor. The methods will be used for detailed analysis of movement patterns and to study the mechanisms of bradykinesia and tremor in Parkinson's disease (PD) and other neurodegenerations. We also want to demonstrate functional changes in the cerebral cortex using the NIRS method, based on detection of changes in infrared light emissions, which occur due to the actual concentrations of oxygenated and deoxygenated hemoglobin reflecting neuronal activity in the cortex. The aim will be to demonstrate changes in the activation of the motor cortex related to kinematic parameters recorded using BradykAn and TremAn.
- MeSH
- blízká infračervená spektroskopie MeSH
- horní končetina MeSH
- hypokineze diagnóza MeSH
- lidé MeSH
- nemoci bazálních ganglií MeSH
- pohybové poruchy diagnóza MeSH
- snímání pohybu MeSH
- tremor diagnóza MeSH
- Check Tag
- lidé MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- neurologie
- NLK Publikační typ
- závěrečné zprávy o řešení grantu AZV MZ ČR
BACKGROUND: In adults, motion-onset visual evoked potentials (M-VEPs) with a dominant N2 peak represent a useful diagnostic tool. However, it is difficult to use this type of VEP in children because of the long maturation (up to 18 years) of M-VEPs, which is characterised by a gradual decrease in N2 peak latency and shape development. Moreover, in some children, M-VEPs are difficult to identify with standard stimuli. METHODS: We tested features of M-VEPs in 30 children (7-12 years) with the following set of standard stimuli used in our lab for examining adults ( https://web.lfhk.cuni.cz/elf ): low-contrast translation motion (TM) and expansion/contraction motion (ExCoM) in full field and in periphery (with central 20° masked). In 16 children, a high-contrast TM was also tested. RESULTS: With standard (low-contrast) stimuli, a common M-VEP to TM and to ExCoM was detected in 77 and 83 % of children, respectively. The M-VEPs to ExCoM in the periphery were detected in only 43 % of children. An abnormal dominant P1 peak was found in 9 % of VEPs to TM, 12 % of VEPs to full-field ExCoM and 14 % of VEPs to peripheral ExCoM. The M-VEPs to all low-contrast stimuli displayed large inter-individual latency variability (N2 peak latency differed for more than 100 ms). High contrast (more suitable for the non-mature magnocellular pathway) shortened M-VEP latencies and improved amplitudes. CONCLUSIONS: Our findings show that the maturation of motion perception in children is inter-individually variable, which limits the diagnostic use of M-VEPs.
- MeSH
- citlivost na kontrast fyziologie MeSH
- dítě MeSH
- lidé MeSH
- oči růst a vývoj MeSH
- senzorické prahy fyziologie MeSH
- vnímání pohybu fyziologie MeSH
- zrakové evokované potenciály fyziologie MeSH
- zrakové korové centrum fyziologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The purpose of the study is to show a proposal of an extension of a one-dimensional speckle correlation method, which is primarily intended for determination of one-dimensional object's translation, for detection of general in-plane object's translation. In that view, a numerical simulation of a displacement of the speckle field as a consequence of general in-plane object's translation is presented. The translation components a x and a y representing the projections of a vector a of the object's displacement onto both x- and y-axes in the object plane (x, y) are evaluated separately by means of the extended one-dimensional speckle correlation method. Moreover, one can perform a distinct optimization of the method by reduction of intensity values representing detected speckle patterns. The theoretical relations between the translation components a x and a y of the object and the displacement of the speckle pattern for selected geometrical arrangement are mentioned and used for the testifying of the proposed method's rightness.
- MeSH
- pohyb těles * MeSH
- teoretické modely * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Analysis of gait features provides important information during the treatment of neurological disorders, including Parkinson's disease. It is also used to observe the effects of medication and rehabilitation. The methodology presented in this paper enables the detection of selected gait attributes by Microsoft (MS) Kinect image and depth sensors to track movements in three-dimensional space. METHODS: The experimental part of the paper is devoted to the study of three sets of individuals: 18 patients with Parkinson's disease, 18 healthy aged-matched individuals, and 15 students. The methodological part of the paper includes the use of digital signal-processing methods for rejecting gross data-acquisition errors, segmenting video frames, and extracting gait features. The proposed algorithm describes methods for estimating the leg length, normalised average stride length (SL), and gait velocity (GV) of the individuals in the given sets using MS Kinect data. RESULTS: The main objective of this work involves the recognition of selected gait disorders in both the clinical and everyday settings. The results obtained include an evaluation of leg lengths, with a mean difference of 0.004 m in the complete set of 51 individuals studied, and of the gait features of patients with Parkinson's disease (SL: 0.38 m, GV: 0.61 m/s) and an age-matched reference set (SL: 0.54 m, GV: 0.81 m/s). Combining both features allowed for the use of neural networks to classify and evaluate the selectivity, specificity, and accuracy. The achieved accuracy was 97.2 %, which suggests the potential use of MS Kinect image and depth sensors for these applications. CONCLUSIONS: Discussion points include the possibility of using the MS Kinect sensors as inexpensive replacements for complex multi-camera systems and treadmill walking in gait-feature detection for the recognition of selected gait disorders.
- MeSH
- algoritmy MeSH
- chůze (způsob) * MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- nervová síť MeSH
- Parkinsonova nemoc patofyziologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- studie případů a kontrol MeSH
- zobrazování trojrozměrné metody MeSH
- zrychlení MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
