keyword
MENU ▼
Read by QxMD icon Read
search

Ocular movement

keyword
https://www.readbyqxmd.com/read/28340582/optimisation-of-an-exemplar-oculomotor-model-using-multi-objective-genetic-algorithms-executed-on-a-gpu-cpu-combination
#1
Eleftherios Avramidis, Ozgur E Akman
BACKGROUND: Parameter optimisation is a critical step in the construction of computational biology models. In eye movement research, computational models are increasingly important to understanding the mechanistic basis of normal and abnormal behaviour. In this study, we considered an existing neurobiological model of fast eye movements (saccades), capable of generating realistic simulations of: (i) normal horizontal saccades; and (ii) infantile nystagmus - pathological ocular oscillations that can be subdivided into different waveform classes...
March 24, 2017: BMC Systems Biology
https://www.readbyqxmd.com/read/28336357/assessment-of-vestibulo-ocular-function-without-measuring-eye-movements
#2
Kara H Beaton, Michael Schubert, Mark Shelhamer
BACKGROUND: The vestibulo-ocular reflex (VOR) maintains stable gaze during head motion. Deficiencies lead to apparent world motion due to incomplete stabilization of eyes in space. VOR measurement requires specialized apparatus, trained operators, and significant setup time. NEW METHOD: We present a system (VON: vestibulo-ocular nulling) for rapid vestibulo-ocular assessment without measuring eye movements per se. VON uses a head-mounted motion sensor, laptop computer with user input control, and laser target whose position is controlled by the computer...
March 20, 2017: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/28330041/retinal-tractography-influence-of-diffusion-acquisition-ocular-laterality-and-ocular-dominance-in-healthy-subjects
#3
Clément Jean, Arnaud Attyé, Sylvie Grand, Augustin Lecler, Christophe Chiquet, Florent Aptel, Laurent Lamalle, Alexandre Krainik
PURPOSE: Exploration of the human retina has never been described with MRI tractography, supposedly because of ocular movement-related artifacts and imaging distortions with EPI diffusion acquisition. In this work, we used track-weighting imaging to assess retinal fascicles. Diffusion acquisition parameters influence was studied and the relationship between variability and ocular laterality and ocular dominance was explored. MATERIALS AND METHODS: Twenty healthy subjects underwent MRI, with retinal tractography calculated with the constrained spherical deconvolution model...
March 2017: Journal of Neuroradiology. Journal de Neuroradiologie
https://www.readbyqxmd.com/read/28323487/pathological-eye-movements-influence-on-the-recordings-of-ocular-vestibular-evoked-myogenic-potential
#4
Ting-Hua Yang, Hsin-Lin Chen, Yi-Ho Young
OBJECTIVE: This study investigated the influence of pathological eye movements on the recordings of ocular vestibulo-evoked myogenic potential (oVEMP). METHODS: Ten patients with pathological eye movements of non-vestibular origin (nine congenital nystagmus and one opsoclonus) who had negative MRI result were assigned to Group A. Another 20 vestibular neuritis (VN) patients with spontaneous nystagmus were assigned to Group B. Both groups underwent audiometry, and caloric, oVEMP and cervical VEMP (cVEMP) tests...
March 21, 2017: Acta Oto-laryngologica
https://www.readbyqxmd.com/read/28303385/after-effects-of-cerebellar-continuous-theta-burst-stimulation-on-reflexive-saccades-and-smooth-pursuit-in-humans
#5
Silvia Colnaghi, P Colagiorgio, S Ramat, E D'Angelo, G Koch, M Versino
The use of cerebellar repetitive transcranial magnetic stimulation has been attempted for perturbing reflexive and voluntary eye movements, but discrepancies are seen between the results of distinct studies possibly due to the different stimulation sites, intensities, and paradigms. We describe the after effects of 20 and 40 s continuous Theta Burst Stimulation (cTBS) as compared to sham stimulation, applied over the lateral cerebellar vermis and paravermis on Reflexive Saccades (RS) and Smooth Pursuit (SP) eye movements, recorded in the 30 min following stimulation...
March 16, 2017: Cerebellum
https://www.readbyqxmd.com/read/28300605/a-rapid-quantification-of-binocular-misalignment-without-recording-eye-movements-vertical-and-torsional-alignment-nulling
#6
Kara H Beaton, Mark J Shelhamer, Dale C Roberts, Michael C Schubert
BACKGROUND: Small, innate asymmetries between the left and right otolith organs can cause ocular misalignment with symptoms that include double vision and motion sickness. Additionally, ocular misalignment affects nearly 5% of the US population. We have developed a portable, non-invasive technology that uses subjective perception of binocular visual signals to estimate relative binocular alignment. NEW METHOD AND RESULTS: The Vertical Alignment Nulling (VAN) and Torsional Alignment Nulling (TAN) tests ask subjects to view one red and one blue line on a tablet computer while looking through color-matched red and blue filters so that each eye sees only one of the lines...
March 11, 2017: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/28299356/an-exome-sequencing-study-of-moebius-syndrome-including-atypical-cases-reveals-an-individual-with-cfeom3a-and-a-tubb3-mutation
#7
Ronak M Patel, David Liu, Claudia Gonzaga-Jauregui, Shalini Jhangiani, James T Lu, V Reid Sutton, Susan D Fernbach, Mahshid Azamian, Lisa White, Jane C Edmond, Evelyn A Paysse, John W Belmont, Donna Muzny, James R Lupski, Richard A Gibbs, Richard Alan Lewis, Brendan H Lee, Seema R Lalani, Philippe M Campeau
Moebius syndrome is characterized by congenital unilateral or bilateral facial and abducens nerve palsies (sixth and seventh cranial nerves) causing facial weakness, feeding difficulties, and restricted ocular movements. Abnormalities of the chest wall such as Poland anomaly and variable limb defects are frequently associated with this syndrome. Most cases are isolated; however, rare families with autosomal dominant transmission with incomplete penetrance and variable expressivity have been described. The genetic basis of this condition remains unknown...
March 2017: Cold Spring Harbor Molecular Case Studies
https://www.readbyqxmd.com/read/28292832/functional-organization-of-vestibulo-ocular-responses-in-abducens-motoneurons
#8
Haike Dietrich, Stefan Glasauer, Hans Straka
Vestibulo-ocular reflexes (VOR) are the dominating contributors to gaze stabilization in all vertebrates. During horizontal head movements, abducens motoneurons form the final element of the reflex arc that integrates visuo-vestibular inputs into temporally precise motor commands for the lateral rectus eye muscle. Here, we studied a possible differentiation of abducens motoneurons into subtypes by evaluating their morphology, discharge properties and synaptic pharmacology in semi-intact in vitro preparations of larval Xenopus laevis Extracellular nerve recordings during sinusoidal head motion revealed a continuum of resting rates and activation thresholds during vestibular stimulation...
March 14, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28291193/-surgical-rehabilitation-of-patients-with-thyroid-eye-disease-systematic-approach
#9
S E Avetisov, Ya O Grusha, D S Ismailova, P A Kochetkov, S S Danilov, N Yu Sviridenko
AIM: to analyze the results of surgical treatment of patients with thyroid eye disease (TED), including the type of surgery, indications, and outcomes. MATERIAL AND METHODS: Hundred thirty-nine patients with TED (112 females, 27 males) aged 45.8±13.6 years. RESULTS: Bony orbital decompression was performed in 91 patients (128 orbits). After the surgery, visual acuity increased from 0.84±0.47 up to 0.94±0.32 (р<0.05), exophthalmos got reduced by the average of 3...
2017: Vestnik Oftalmologii
https://www.readbyqxmd.com/read/28284903/ocular-and-visual-disorders-in-parkinson-s-disease-common-but-frequently-overlooked
#10
REVIEW
Merel S Ekker, Sabine Janssen, Klaus Seppi, Werner Poewe, Nienke M de Vries, Thomas Theelen, Jorik Nonnekes, Bastiaan R Bloem
Patients with Parkinson's disease (PD) often compensate for their motor deficits by guiding their movements visually. A wide range of ocular and visual disorders threatens the patients' ability to benefit optimally from visual feedback. These disorders are common in patients with PD, yet they have received little attention in both research and clinical practice, leading to unnecessary - but possibly treatable - disability. Based on a literature search covering 50 years, we review the range of ocular and visual disorders in patients with PD, and classify these according to anatomical structures of the visual pathway...
February 21, 2017: Parkinsonism & related Disorders
https://www.readbyqxmd.com/read/28284887/downbeat-nystagmus-due-to-ranitidine-in-a%C3%A2-pediatric-patient
#11
Laura Butragueño Laiseca, Blanca Toledo Del Castillo, Cristina Rodríguez Jimenez, Silvia Manrique-Rodríguez, Jimena Pérez Moreno
BACKGROUND: Ranitidine has not been considered as a potential cause of ocular movement conditions. However, it is known that the vestibular nucleus complex, that has a key role in gaze control and vestibule-ocular reflexes, receives hypothalamic histaminergic innervations. Some studies reported the effect of ranitidine blocking the excitatory responses of vestibular nuclei neurons to histamine. CASE REPORT: We report the first case of a downbeat nystagmus secondary to ranitidine in an infant...
February 11, 2017: European Journal of Paediatric Neurology: EJPN
https://www.readbyqxmd.com/read/28273704/-clinical-and-genetic-characteristics-of-children-with-leigh-syndrome
#12
F Fang, Y Shen, D M Shen, Z M Liu, C H Ding, W C Zhang, S Z Sun, J L Lyu, T L Han, X H Wang, W H Zhang, X Y Yang, J W Li, H S Wu
Objective: To investigate the clinically and genetic characteristics of children with Leigh syndrome. Method: Patients with clinically diagnosed Leigh syndrome(LS)in the department of Neurology, Beijing Children's Hospital from January 2013 to February 2016 underwent the mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) detecting with next generation sequencing (NGS) technology. The clinical data of gene confirmed cases were retrospectively collected and analyzed. The differences in the onset age, clinical manifestations, lactic acid level and MRI results between the mtDNA variation and nDNA variation were compared and analyzed...
March 2, 2017: Zhonghua Er Ke za Zhi. Chinese Journal of Pediatrics
https://www.readbyqxmd.com/read/28271408/moving-or-being-moved-that-makes-a-difference
#13
Hans Straka, Boris P Chagnaud
During head/body movements, gaze stability is ensured by transformation of motion-related sensory signals into respective motor commands. Passively induced motion in all vertebrates including amphibians evokes a robust vestibulo-ocular reflex, suggesting an equally important role of this motor reaction during actively induced motion. However, during self-induced movements including locomotion, motor efference copies offer a convenient additional substrate for counteracting retinal image displacements. During such locomotor activity in Xenopus laevis tadpoles, spinal central pattern generator-derived efference copies elicit spatio-temporally specific eye movements, which are functionally appropriate to offset swimming-related retinal image displacements...
March 7, 2017: Journal of Neurology
https://www.readbyqxmd.com/read/28268622/unscented-kalman-filter-for-neural-decoding-of-human-treadmill-walking-from-non-invasive-electroencephalography
#14
Trieu Phat Luu, Yongtian He, Sho Nakagame, Jeffrey Gorges, Kevin Nathan, Jose L Contreras-Vidal
The feasibility of decoding lower limb kinematics in human treadmill walking from noninvasive electroencephalography (EEG) has been demonstrated with linear Wiener filter. However, nonlinear relationship between neural activities and limb movements may challenge the linear decoders in real-time brain computer interface (BCI) applications. In this study, we propose a nonlinear neural decoder using an Unscented Kalman Filter (UKF) to infer lower limb joint angles from noninvasive scalp EEG signals during human treadmill walking...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28268468/detection-of-myasthenia-gravis-using-electrooculography-signals
#15
T Liang, M I Boulos, B J Murray, S Krishnan, H Katzberg, K Umapathy
Myasthenia gravis (MG) is an autoimmune neuromuscular disorder resulting from skeletal muscle weakness and fatigue. An early common symptom is fatigable weakness of the extrinsic ocular muscles; if symptoms remain confined to the ocular muscles after a few years, this is classified as ocular myasthenia gravis (OMG). Diagnosis of MG when there are mild, isolated ocular symptoms can be difficult, and currently available diagnostic techniques are insensitive, non-specific or technically cumbersome. In addition, there are no accurate biomarkers to follow severity of ocular dysfunction in MG over time...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28259139/infectious-keratoconjunctivitis-in-wild-caprinae-merging-field-observations-and-molecular-analyses-sheds-light-on-factors-shaping-outbreak-dynamics
#16
Giuseppina Gelormini, Dominique Gauthier, Edy M Vilei, Jean-Paul Crampe, Joachim Frey, Marie-Pierre Ryser-Degiorgis
BACKGROUND: Infectious keratoconjunctivitis (IKC) is an ocular infectious disease caused by Mycoplasma conjunctivae which affects small domestic and wild mountain ruminants. Domestic sheep maintain the pathogen but the detection of healthy carriers in wildlife has raised the question as to whether M. conjunctivae may also persist in the wild. Furthermore, the factors shaping the dynamics of IKC outbreaks in wildlife have remained largely unknown. The aims of this study were (1) to verify the etiological role of M...
March 4, 2017: BMC Veterinary Research
https://www.readbyqxmd.com/read/28258574/aquaporins-in-the-eye
#17
Thuy Linh Tran, Steffen Hamann, Steffen Heegaard
The major part of the eye consists of water . Continuous movement of water and ions between the ocular compartments and to the systemic circulation is pivotal for many physiological functions in the eye. The movement of water facilitates removal of the many metabolic products of corneal-, ciliary body-, lens- and retinal metabolism, while maintaining transparency in the optical compartments. Transport across the corneal epithelium and endothelium maintains the corneal transparency. Also, aqueous humour is continuously secreted by the epithelia of the ciliary body and maintains the intraocular pressure...
2017: Advances in Experimental Medicine and Biology
https://www.readbyqxmd.com/read/28243486/abnormal-spontaneous-eye-movements-as-initial-presentation-of-organophosphate-poisoning
#18
Igor De Lima Teixeira, Silméia Garcia Zanati Bazan, Arthur Oscar Schelp, Gustavo José Luvizutto, Fabrício Diniz De Lima, Rodrigo Bazan
BACKGROUND: Atypical ocular bobbing may result from an intentional poisoning from an organophosphate compound. PHENOMENOLOGY SHOWN: The patient exhibited conjugated, slow, arrhythmic, unpredictable eye movements in all directions, diagnosed as atypical ocular bobbing. EDUCATIONAL VALUE: This is a rare, well-documented, clinically relevant case for medical students for correct diagnosis and appropriate treatment of organophosphate intoxication...
2017: Tremor and Other Hyperkinetic Movements
https://www.readbyqxmd.com/read/28242738/neuronal-control-of-fixation-and-fixational-eye-movements
#19
REVIEW
Richard J Krauzlis, Laurent Goffart, Ziad M Hafed
Ocular fixation is a dynamic process that is actively controlled by many of the same brain structures involved in the control of eye movements, including the superior colliculus, cerebellum and reticular formation. In this article, we review several aspects of this active control. First, the decision to move the eyes not only depends on target-related signals from the peripheral visual field, but also on signals from the currently fixated target at the fovea, and involves mechanisms that are shared between saccades and smooth pursuit...
April 19, 2017: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
https://www.readbyqxmd.com/read/28242737/unchanging-visions-the-effects-and-limitations-of-ocular-stillness
#20
REVIEW
Susana Martinez-Conde, Stephen L Macknik
Scientists have pondered the perceptual effects of ocular motion, and those of its counterpart, ocular stillness, for over 200 years. The unremitting 'trembling of the eye' that occurs even during gaze fixation was first noted by Jurin in 1738. In 1794, Erasmus Darwin documented that gaze fixation produces perceptual fading, a phenomenon rediscovered in 1804 by Ignaz Paul Vital Troxler. Studies in the twentieth century established that Jurin's 'eye trembling' consisted of three main types of 'fixational' eye movements, now called microsaccades (or fixational saccades), drifts and tremor...
April 19, 2017: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
keyword
keyword
107801
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"