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Готові списки джерел за темами / Transcranial simulations

Добірка наукової літератури з теми "Transcranial simulations"

Автор: Grafiati

Опубліковано: 7 липня 2024

Оновлено: 7 липня 2024

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Статті в журналах з теми "Transcranial simulations":

1

Antal, Andrea, and Christoph S. Herrmann. "Transcranial Alternating Current and Random Noise Stimulation: Possible Mechanisms." Neural Plasticity 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/3616807.

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Background. Transcranial alternating current stimulation (tACS) is a relatively recent method suited to noninvasively modulate brain oscillations. Technically the method is similar but not identical to transcranial direct current stimulation (tDCS). While decades of research in animals and humans has revealed the main physiological mechanisms of tDCS, less is known about the physiological mechanisms of tACS.Method. Here, we review recent interdisciplinary research that has furthered our understanding of how tACS affects brain oscillations and by what means transcranial random noise stimulation (tRNS) that is a special form of tACS can modulate cortical functions.Results. Animal experiments have demonstrated in what way neurons react to invasively and transcranially applied alternating currents. Such findings are further supported by neural network simulations and knowledge from physics on entraining physical oscillators in the human brain. As a result, fine-grained models of the human skull and brain allow the prediction of the exact pattern of current flow during tDCS and tACS. Finally, recent studies on human physiology and behavior complete the picture of noninvasive modulation of brain oscillations.Conclusion. In future, the methods may be applicable in therapy of neurological and psychiatric disorders that are due to malfunctioning brain oscillations.

2

Vyas, Urvi, Elena Kaye, and Kim Butts Pauly. "Transcranial phase aberration correction using beam simulations and MR-ARFI." Medical Physics 41, no. 3 (February 26, 2014): 032901. http://dx.doi.org/10.1118/1.4865778.

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3

Sigona, Michelle K., Thomas J. Manuel, Huiwen Luo, Marshal A. Phipps, Pai-Feng Yang, Kianoush Banaie Boroujeni, Robert L. Treuting, et al. "Generating patient-specific acoustic simulations for transcranial focused ultrasound procedures based on optical tracking information." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A155. http://dx.doi.org/10.1121/10.0015868.

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During transcranial focused ultrasound (FUS) procedures, accurate targeting is important and neuronavigation with optically tracked tools is used to estimate the free-field focal location on pre-acquired images. Offline neuronavigation systems do not typically incorporate aberrating effects of the skull known to displace and distort the focus. Here, we developed a pipeline that integrated patient-specific acoustic simulations informed by transformations from optically tracked FUS procedures as a tool to evaluate transcranial pressure fields and demonstrated its use in three FUS scenarios: magnetic resonance imaging-guided (MR-guided) phantom experiments, MR-guided non-human primate (NHP) experiments, an offline behaving NHP experiments. Distance vectors between the estimated focus from optical tracking and peak intracranial location from simulations were less than 1 mm for all groups (Phantom: 0.6 ± 0.3 mm, NHP: 0.7 ± 0.3 mm, Behaving NHP: 0.5 ± 0.2 mm). Comparisons of the target registration error of MR measurements with the optically tracked focus (TRETracked) and simulated focus (TRESimulated) suggest that focal location errors are dominated by optical tracking errors rather than aberration through the skull in the NHP (Phantom: TRETracked: 3.3 ± 1.4 mm, Phantom TRESimulated: 3.3 ± 1.9 mm, NHP TRETracked: 3.9 ± 1.9 mm, NHP TRESimulated: 4.1 ± 1.6 mm). Our software pipeline provides patient-specific estimates of the acoustic field during transcranial FUS procedures.

4

Angla, Célestine, Benoit Larrat, Jean-Luc Gennisson, and Sylvain Chatillon. "Improved skull bone acoustic property homogenization for fast transcranial ultrasound simulations." Journal of Physics: Conference Series 2768, no. 1 (May 1, 2024): 012006. http://dx.doi.org/10.1088/1742-6596/2768/1/012006.

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Abstract Transcranial ultrasound simulations are crucial to optimize and secure ultrasound interventions in brain therapy, depending on the patient skull. When performing such simulations, accurate modeling of the skull is essential, although very challenging, because of the inter/intra sample property variability. Simulations based on semi-analytical methods require a homogeneous description of the skull. Averaging the acoustic property maps derived from the CT scan does not modify the focus shift, but it leads to an overestimation of the pressure field amplitude. The purpose of this work is to provide a homogenization method that compensates for this amplitude overestimation. First, the skull acoustic property maps are segmented into a three-layer medium to represent the different types of skull bone (cortical – trabecular – cortical). Then, equivalent properties are computed so as to minimize the time of flight and transmission coefficient errors between the three-layer medium and the one-layer equivalent medium. This method was validated using 3D simulations with CIVA Healthcare and k-Wave and has proven to be very efficient.

5

Dougherty, Edward T., James C. Turner, and Frank Vogel. "Multiscale Coupling of Transcranial Direct Current Stimulation to Neuron Electrodynamics: Modeling the Influence of the Transcranial Electric Field on Neuronal Depolarization." Computational and Mathematical Methods in Medicine 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/360179.

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Transcranial direct current stimulation (tDCS) continues to demonstrate success as a medical intervention for neurodegenerative diseases, psychological conditions, and traumatic brain injury recovery. One aspect of tDCS still not fully comprehended is the influence of the tDCS electric field on neural functionality. To address this issue, we present a mathematical, multiscale model that couples tDCS administration to neuron electrodynamics. We demonstrate the model’s validity and medical applicability with computational simulations using an idealized two-dimensional domain and then an MRI-derived, three-dimensional human head geometry possessing inhomogeneous and anisotropic tissue conductivities. We exemplify the capabilities of these simulations with real-world tDCS electrode configurations and treatment parameters and compare the model’s predictions to those attained from medical research studies. The model is implemented using efficient numerical strategies and solution techniques to allow the use of fine computational grids needed by the medical community.

6

Amanatiadis, Stamatis A., Georgios K. Apostolidis, Chrysanthi S. Bekiari, and Nikolaos V. Kantartzis. "Transcranial ultrasonic propagation and enhanced brain imaging exploiting the focusing effect of the skull." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 39, no. 3 (June 5, 2020): 671–82. http://dx.doi.org/10.1108/compel-10-2019-0387.

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Purpose The reliable transcranial imaging of brain inner structures for diagnostic purposes is deemed crucial owing to the decisive importance and contribution of the brain in human life. The purpose of this paper is to investigate the potential application of medical ultrasounds to transcranial imaging using advanced techniques, such as the total focussing method. Design/methodology/approach Initially, the fundamental details of the total focussing method are presented, while the skull properties, such as the increased acoustic velocity and scattering, are thoroughly examined. Although, these skull characteristics constitute the main drawback of typical transcranial ultrasonic propagation algorithms, they are exploited to focus the acoustic waves towards the brain. To this goal, a virtual source is designed, considering the wave refraction, to efficiently correct the reconstructed brain image. Finally, the verification of the novel method is conducted through numerical simulations of various realistic setups. Findings The theoretically designed virtual source resembles a focussed sensor; therefore, the directivity increment, owing to the propagation through the skull, is confirmed. Moreover, numerical simulations of real-world scenarios indicate that the typical artifacts of the conventional total focussing method are fully overcome because of the increased directivity of the proposed technique, while the reconstructed image is efficiently corrected when the proposed virtual source is used. Originality/value A new systematic methodology along with the design of a flexible virtual source is developed in this paper for the reliable and precise transcranial ultrasonic image reconstruction of the brain. Despite the slight degradation owing to the skull scattering, the combined application of the total focussing method and the featured virtual source can successfully detect arbitrary anomalies in the brain that cannot be spotted by conventional techniques.

7

Palatnik de Sousa, Iam, Carlos R. H. Barbosa, and Elisabeth Costa Monteiro. "Safe exposure distances for transcranial magnetic stimulation based on computer simulations." PeerJ 6 (June 18, 2018): e5034. http://dx.doi.org/10.7717/peerj.5034.

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The results of a computer simulation examining the compliance of a given transcranial magnetic stimulation device to the 2010 International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines are presented. The objective was to update the safe distance estimates with the most current safety guidelines, as well as comparing these to values reported in previous publications. The 3D data generated was compared against results available in the literature, regarding the MCB-70 coil by Medtronic. Regarding occupational exposure, safe distances of 1.46 m and 0.96 m are derived from the simulation according to the 2003 and 2010 ICNIRP guidelines, respectively. These values are then compared to safe distances previously reported in other studies.

8

Zangemeister, Wolfgang H., and Volker Hoemberg. "Eye model simulations of saccadic impairment through transcranial magnetic stimulation (TMS." Neuro-Ophthalmology 13, no. 2 (January 1993): 89–97. http://dx.doi.org/10.3109/01658109309037010.

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9

Pasquinelli, Cristina, Hazael Montanaro, Hyunjoo J. Lee, Lars G. Hanson, Hyungkook Kim, Niels Kuster, Hartwig R. Siebner, Esra Neufeld, and Axel Thielscher. "Transducer modeling for accurate acoustic simulations of transcranial focused ultrasound stimulation." Journal of Neural Engineering 17, no. 4 (July 13, 2020): 046010. http://dx.doi.org/10.1088/1741-2552/ab98dc.

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10

Drainville, Robert Andrew, Sylvain Chatillon, David Moore, John Snell, Frederic Padilla, and Cyril Lafon. "A simulation study on the sensitivity of transcranial ray-tracing ultrasound modeling to skull properties." Journal of the Acoustical Society of America 154, no. 2 (August 1, 2023): 1211–25. http://dx.doi.org/10.1121/10.0020761.

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In transcranial focused ultrasound therapies, such as treating essential tremor via thermal ablation in the thalamus, acoustic energy is focused through the skull using a phased-array transducer. Ray tracing is a computationally efficient method that can correct skull-induced phase aberrations via per-element phase delay calculations using patient-specific computed tomography (CT) data. However, recent studies show that variations in CT-derived Hounsfield unit may account for only 50% of the speed of sound variability in human skull specimens, potentially limiting clinical transcranial ultrasound applications. Therefore, understanding the sensitivity of treatment planning methods to material parameter variations is essential. The present work uses a ray-tracing simulation model to explore how imprecision in model inputs, arising from clinically significant uncertainties in skull properties or considerations of acoustic phenomena, affects acoustic focusing quality through the skull. We propose and validate new methods to optimize ray-tracing skull simulations for clinical treatment planning, relevant for predicting intracranial target's thermal rise, using experimental data from ex-vivo human skulls.

Більше джерел

Дисертації з теми "Transcranial simulations":

1

Angla, Célestine. "Fast transcranial acoustic simulations for personalized dosimetry in ultrasound brain therapy." Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPAST207.

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La thérapie par ultrasons de pathologies cérébrales est très prometteuse, notamment pour son caractère non invasif lorsque la sonde ultrasonore reste externe au crâne. Cependant, la structure complexe de l'os du crâne atténue et perturbe fortement la propagation du faisceau ultrasonore, ce qui altère les dimensions, la position et l'intensité de la tâche focale. Or ces paramètres focaux doivent être parfaitement maitrisés pour assurer à la fois l'efficacité et la sureté du traitement. En raison de la grande variabilité inter et intra individus de la géométrie et des propriétés acoustiques du crâne, des simulations personnalisées sont nécessaires pour prédire les caractéristiques focales en fonction du patient et de la position de la sonde ultrasonore. La plupart des méthodes de simulations utilisées actuellement, telles que k-Wave, sont très gourmandes en temps de calcul et en espace mémoire, ce qui les limite à des outils de planning pré-intervention. L'objectif de cette thèse était de développer une méthode semi-analytique rapide et réaliste de calcul de champ ultrasonore au travers du crâne. Dans un premier temps, un modèle lisse et homogène du crâne, réaliste et favorable aux algorithmes de calcul de champ rapides, a été développé. Pour cela, les surfaces internes et externes du crâne ont été modélisées en utilisant une méthode appelée « Multi-level Bspline Approximation », et une méthode d'homogénéisation des propriétés acoustiques du crâne a été développée et validée numériquement. Ce modèle de crâne lisse et homogène a ensuite été utilisé en entrée de l'algorithme de calcul de champ développé. Cet algorithme, nommé SplineBeam, est basé sur une méthode de calcul des trajets ultrasonores par minimisation de la fonction temps de vol, qui est rapide et précise, et qui, combinée à la méthode des pinceaux, permet un échantillonnage régulier de la sonde ultrasonore. SplineBeam a été validé numériquement, par comparaison avec le modèle pinceau, implémenté dans la plateforme de simulation CIVA HealthCare, développée au CEA, et avec d'autres solvers numériques (dont k-Wave) sur une série de configurations, et expérimentalement, par comparaisons avec des champs de pressions acquis par hydrophone au travers d'un échantillon de crâne ex vivo. Les champs simulés avec SplineBeam se sont avérés être plus proches des champs mesurés expérimentalement que les champs simulés avec k-Wave, ce qui valide à la fois le modèle du crâne et la méthode de calcul de champ. De plus, SplineBeam peut restreindre son calcul à la tâche focale, ce qui, pour une grande sonde, lui permet de réduire drastiquement le nombre de points de calcul et d'avoir des temps de calcul de deux ordres inférieurs à ceux de k-Wave
Ultrasound brain therapy is a promising method, as it is non-invasive when ultrasonic waves are sent through the skull. However, the skull bone complex structure strongly attenuates and aberrates the ultrasound beam, altering the dimensions, position and intensity of the focal spot. These focal parameters must be perfectly controlled to ensure both treatment efficacy and safety. Due to the high inter/intra-individual variability of skull geometry and acoustic properties, personalized simulations are required to predict focal characteristics depending on the patient skull and the ultrasonic probe position. Most simulation methods currently in use, such as k-Wave, are very time- and memory-intensive, limiting them to pre-intervention planning tools. The aim of this thesis was to develop a fast and realistic semi-analytical method for ultrasound field computation through the skull. As a first step, we developed a smooth and homogeneous model of the skull, realistic and suited to fast field computation algorithms. To this end, we modeled the skull inner and outer surfaces using a method called "Multi-level Bspline Approximation", and we developed a skull acoustic property homogenization method, which was numerically validated. This smooth and homogeneous skull model was then used as input to the field computation algorithm developed. This algorithm, named SplineBeam, is based on an ultrasonic path computation method that minimizes the time-of-flight function, which is fast and accurate, and which, combined with the pencil method, enables a regular sampling of the ultrasound probe. SplineBeam was validated numerically, by comparison with the pencil method, embedded in the CIVA HealthCare simulation platform, developed at the CEA, and with other numerical solvers (including k-Wave) on a series of configurations, and experimentally, by comparison with hydrophone measured pressure fields through an ex vivo skull sample. SplineBeam simulated fields were found to be closer to the experimentally measured ones than those simulated with k-Wave. This validates both the skull model and the field computation method. Furthermore, SplineBeam can restrict its computation to the focal spot, which allows it to drastically reduce the number of computation points, making it faster than k-Wave by two orders of magnitude, for a large probe

2

Syeda, Farheen. "Development of Novel Models to Study Deep Brain Effects of Cortical Transcranial Magnetic Stimulation." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5517.

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Neurological disorders require varying types and degrees of treatments depending on the symptoms and underlying causes of the disease. Patients suffering from medication-refractory symptoms often undergo further treatment in the form of brain stimulation, e.g. electroconvulsive therapy (ECT), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), or transcranial magnetic stimulation (TMS). These treatments are popular and have been shown to relieve various symptoms for patients with neurological conditions. However, the underlying effects of the stimulation, and subsequently the causes of symptom-relief, are not very well understood. In particular, TMS is a non-invasive brain stimulation therapy which uses time-varying magnetic fields to induce electric fields on the conductive parts of the brain. TMS has been FDA-approved for treatment of major depressive disorder for patients refractory to medication, as well as symptoms of migraine. Studies have shown that TMS has relieved severe depressive symptoms, although researchers believe that it is the deeper regions of the brain which are responsible for symptom relief. Many experts theorize that cortical stimulation such as TMS causes brain signals to propagate from the cortex to these deep brain regions, after which the synapses of the excited neurons are changed in such a way as to cause plasticity. It has also been widely observed that stimulation of the cortex causes signal firing at the deeper regions of the brain. However, the particular mechanisms behind TMS-caused signal propagation are unknown and understudied. Due to the non-invasive nature of TMS, this is an area in which investigation can be of significant benefit to the clinical community. We posit that a deeper understanding of this phenomenon may allow clinicians to explore the use of TMS for treatment of various other neurological symptoms and conditions. This thesis project seeks to investigate the various effects of TMS in the human brain, with respect to brain tissue stimulation as well as the cellular effects at the level of neurons. We present novel models of motor neuron circuitry and fiber tracts that will aid in the development of deep brain stimulation modalities using non-invasive treatment paradigms.

3

Robertson, James. "Accurate simulation of low-intensity transcranial ultrasound propagation for neurostimulation." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1574816/.

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Neural stimulation with low-intensity ultrasound is a potentially transformative technology with applications in therapy and research. To develop, it will require ultrasound to be tightly focused on brain structures with accurate spatial targeting and fine control over the ultrasound amplitude at the target. However, the skull is an impediment to the effective focusing of ultrasound. Simulations of ultrasound propagation through acoustic property maps derived from medical images can be used to derive focusing drive signals for multi-element arrays. Focusing effectiveness is dependent on the fidelity of the numerical simulations. In combination with MRI based treatment verification, model based focusing has been used to focus high-intensity ultrasound onto the brain for ablation. This thesis presents a thorough and systematic study of the simulation parameters required to achieve effective transcranial focusing. The literature on ultrasonic neurostimulation, transcranial ultrasonic focusing, and the derivation of property maps from medical images is reviewed. The sampling criteria required to ensure numerical accuracy for the k-space pseudospectral time domain simulation scheme is established through testing of individual sources of numerical error, and convergence testing of a simulated time-reversal protocol. With numerical accuracy assured, the importance of acoustic property maps is examined through simulations to determine the sensitivity of intracranial fields to the properties of the skull layer. These results are corroborated by matching experimental measurements of ultrasound propagation through skull bone phantoms with spatially registered simulations. Finally, the impact of image related homogenisation and loss of internal bone structure is determined using simulations through co-registered clinical CT and micro-CT data of the skull.

4

Wagner, Timothy A. (Timothy Andrew) 1974. "Field distributions within the human cortex induced by transcranial magnetic simulation." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86789.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.
Includes bibliographical references (leaves 120-125).
by Timothy A. Wagner.
S.M.

5

Connor, Christopher W. "Simulation methods and tissue property models for non-invasive transcranial focused ultrasound surgery." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33070.

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Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2005.
Includes bibliographical references.
Many brain tumors are localized deeply and are currently surgically inaccessible without causing severe damage to the overlying structures of the brain. The current spectrum of non-invasive methods for treating such tumors includes radiotherapy, which requires exposure to ionizing radiation, and chemotherapy, which is systemically toxic. However, these tumors may also potentially be attacked by focusing highly intense ultrasound onto them. Focused ultrasound surgery is without the side effects of radiotherapy and chemotherapy, and the therapeutic effect of ultrasound therapy can be monitored in real- time using the proton chemical shift MRI technique. However, in order for brain tumors to be treated non-invasively, the ultrasound must be focused onto the targeted brain tissue through the intact cranium. Transcranial focusing of ultrasound is a longstanding and difficult problem as skull is a highly heterogeneous material. As the ultrasound field propagates through the bones of the skull, it undergoes substantatial distortion due to the variations in density and speed of sound therein. There is substantial individual variation in skull size, thickness and composition. Furthermore, the acoustic attenuation coefficient in bone is high, so the skull may also be heated by the ultrasound propagating through it. This thesis contains novel simulation techniques for analyzing transcranial acoustic propagation and for analyzing the temperature changes so produced in the brain, skull and scalp. These techniques have also been applied to modeling non-invasive treatment of the liver, and to producing therapeutic ultrasound fields that harness non-linear acoustic effects advantageously.
(cont.) The thesis also contains unified models for the speed of sound and the acoustic attenuation coeffiecient in human skull. These models were generated by combining genetic optimization algorithms, acoustic propagation modeling and empirical measurement of intracranial ultrasound fields; they are valid across the full range of trabecular and cortical cranial bone.
by Christopher W. Connor.
Ph.D.

6

Kuppuswamy, Annapoorna. "Cortical plasticity and functional change in human spinal cord injury investigated using repetitive transcranial magnetic simulation." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502919.

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7

Hurdal, Monica Kimberly. "Mathematical and computer modelling of the human brain with reference to cortical magnification and dipole source localisation in the visual cortx." Thesis, Queensland University of Technology, 1998.

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8

Schabrun, Siobhan M. "Experimentally induced cortical plasticity: neurophysiological and functional correlates in health and disease." 2010. http://hdl.handle.net/2440/56534.

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Neuroplasticity provides the basis for many of our most fundamental processes including learning, memory and the recovery of function following injury. This thesis is concerned with the neurophysiological and functional correlates of sensorimotor neuroplasticity in the healthy and focal dystonic populations. My initial experiments were conducted to determine the functional correlates of neuroplasticity induced in the primary motor (M1) and primary sensory (S1) cortices during a grip lift task. In healthy subjects these experiments further quantified the role of M1 in the anticipatory control of grip force scaling and demonstrated a role for S1 in triggering subsequent phases of the motor plan. My second series of experiments served to extend these findings by examining the functional correlates of neuroplasticity induced in the supplementary motor area (SMA). This study provided evidence for the role of left SMA in the control of grip force scaling and a role for left and right SMA in the synchronization of grip force and load force during the grip-lift synergy. Afferent input is known to be a powerful driver of cortical reorganisation. In particular, the timing and pattern of afferent input is thought to be crucial to the induction of plastic change. In healthy subjects, I examined the neurophysiological effects of applying “associative” (synchronous) and “non-associative” (asynchronous) patterns of afferent input to the motor points or digits of the hand. I observed an increase in the volume and area of the cortical representation of stimulated muscles when associative stimulation was applied over the motor points of two hand muscles. This pattern of stimulation also caused the centres of gravity of the stimulated muscles to move closer together, mimicking the maladaptive changes seen in focal hand dystonia. Non-associative stimulation and stimulation applied to the digits did not produce such an effect. Task-specific focal dystonia is characterised by excessive representational plasticity resulting in cortical representations which are significantly larger, and demonstrate greater overlap, than those seen in healthy individuals. These changes are thought to be driven, in part, by repetitive movement patterns which promote associative patterns of afferent input over an extended time period. On the basis of this knowledge, I applied non-associative stimulation to the hand muscles of dystonic subjects. Following this intervention, I noted a contraction of representational maps and a separation in the centres of gravity of the stimulated muscles. These neurophysiological changes were accompanied by improvements on a cyclic drawing task. This thesis demonstrates the functional correlates of neuroplasticity in M1, S1 and SMA during object manipulation using a precision grasp. These findings further extend our knowledge on the mechanisms underlying effective grasp control and assist us in the development of future rehabilitation protocols for neurological conditions involving grasp dysfunction. In addition, this thesis is the first to demonstrate an improvement in both neurophysiological and functional measures in focal dystonia following a period of non-associative afferent stimulation. These results open up exciting new avenues for the development of effective treatment protocols in those with focal hand dystonia.
Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2010

9

Royal, Isabelle. "Simulation de l'amusie dans le cerveau normal." Thèse, 2017. http://hdl.handle.net/1866/20624.

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10

Cazzato, Valentina, S. Mele, and C. Urgesi. "Gender differences in the neural underpinning of perceiving and appreciating the beauty of the body." 2014. http://hdl.handle.net/10454/9856.

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Although previous studies have suggested a certain degree of right hemisphere dominance for the response of extrastriate body area (EBA) during body perception, recent evidence suggests that this functional lateralization may differ between men and women. It is unknown, however, whether and how gender differences in body perception affect appreciating the beauty of the body of conspecifics. Here, we applied five 10-Hz repetitive transcranial magnetic stimulation (rTMS) pulses over left and right EBA and over the vertex to investigate the contribution of visual body representations in the two hemispheres on esthetic body perception. Female and male healthy volunteers were requested to judge how much they liked opposite- and same-gender virtual model bodies or to judge their weight, thus allowing us to compare the effects of right- and left-EBA rTMS on esthetic (liking) and perceptual (weight) judgments of human bodies. The analysis of the esthetic judgments provided by women revealed that right-EBA rTMS increased the liking judgments of opposite- but not same-gender models, as compared to both vertex and left EBA stimulation. Conversely, in men the liking judgments of opposite-gender models decreased after virtual disruption of both right and left EBA as compared to vertex stimulation. Crucially, no significant effect was found for the perceptual task, showing that left- and right-EBA rTMS did not affect weight perception. Our results provide evidence of gender difference in the hemispheric asymmetry of EBA in the esthetic processing of human bodies, with women showing stronger right hemisphere dominance in comparison with men.

Частини книг з теми "Transcranial simulations":

1

Zaidi, Tayeb, and Kyoko Fujimoto. "Evaluation and Comparison of Simulated Electric Field Differences Using Three Image Segmentation Methods for TMS." In Brain and Human Body Modelling 2021, 75–87. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-15451-5_5.

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AbstractComputational electromagnetic modeling is a powerful technique to evaluate the effects of electrical stimulation of the human brain. The results of these simulations can vary based on the segmentation of the head and brain generated from the patient images. Using an existing boundary element fast multipole method (BEM-FMM) electromagnetic solver, this work compares the simulated electric field differences resulted by the three segmentation methods. A transcranial magnetic stimulation (TMS) coil targeting both the primary motor cortex and the dorsolateral prefrontal cortex (DLPFC) was simulated. Average field differences were small among the three methods (2% for motor cortex, 3% for DLPFC) and the average field differences in the regions directly surrounding the target stimulation point were 5% for the motor cortex and 2% for DLPFC. More studies evaluating different coils and other segmentation options may further improve the computational modeling for robust TMS treatment.

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Antonietti, Alberto, Claudia Casellato, Egidio D’Angelo, and Alessandra Pedrocchi. "Computational Modelling of Cerebellar Magnetic Stimulation: The Effect of Washout." In Lecture Notes in Computer Science, 35–46. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-82427-3_3.

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AbstractNowadays, clinicians have multiple tools that they can use to stimulate the brain, by means of electric or magnetic fields that can interfere with the bio-electrical behaviour of neurons. However, it is still unclear which are the neural mechanisms that are involved and how the external stimulation changes the neural responses at network-level. In this paper, we have exploited the simulations carried out using a spiking neural network model, which reconstructed the cerebellar system, to shed light on the underlying mechanisms of cerebellar Transcranial Magnetic Stimulation affecting specific task behaviour. Namely, two computational studies have been merged and compared. The two studies employed a very similar experimental protocol: a first session of Pavlovian associative conditioning, the administration of the TMS (effective or sham), a washout period, and a second session of Pavlovian associative conditioning. In one study, the washout period between the two sessions was long (1 week), while the other study foresaw a very short washout (15 min). Computational models suggested a mechanistic explanation for the TMS effect on the cerebellum. In this work, we have found that the duration of the washout strongly changes the modification of plasticity mechanisms in the cerebellar network, then reflected in the learning behaviour.

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Curta, C., S. Crisan, and R. V. Ciupa. "3D Simulation Analysis of Transcranial Magnetic Stimulation." In IFMBE Proceedings, 316–19. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-22586-4_66.

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4

Hallaj, Ibrahim M., Robin O. Cleveland, Steven G. Kargl, and Ronald A. Roy. "Fdtd Simulation of Transcranial Focusing Using Ultrasonic Phase-Conjugate Arrays." In Acoustical Imaging, 61–66. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4419-8588-0_10.

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Hart, Robin, Philip D. Hart, and Stuart Bunt. "A Novel Technique for Simulating Transcranial Doppler Examinations In Vitro." In Medical Image Computing and Computer-Assisted Intervention – MICCAI’99, 1226–33. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/10704282_133.

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6

Lu, M., and S. Ueno. "Numerical Simulation of Deep Transcranial Magnetic Stimulation by Multiple Circular Coils." In IFMBE Proceedings, 1663–66. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-00846-2_410.

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Wartman, William A. "Preprocessing General Head Models for BEM-FMM Modeling Pertinent to Brain Stimulation." In Brain and Human Body Modeling 2020, 325–43. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-45623-8_20.

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AbstractIntroduction: Transcranial magnetic stimulation (TMS) is a major noninvasive neurostimulation method in which a coil placed near the head employs electromagnetic induction to produce electric fields and currents within the brain. To predict the actual site of stimulation, numerical simulation of the electric fields within the head using high-resolution subject-specific head models is required. A TMS modeling software toolkit has been developed based on the boundary element fast multipole method (BEM-FMM), which has several advantages over conventional finite element method (FEM) solvers.Objective: To extend the applicability of the BEM-FMM TMS simulation toolkit to head models whose meshing scheme produces a single mesh for every unique tissue instead of producing a single mesh for every unique tissue/tissue boundary.Method: The MIDA model of the IT’IS Foundation, Switzerland, comprises 115 high-resolution tissue models in the form that the BEM-FMM toolkit is modified to accept. The updated BEM-FMM toolkit is tested using this head model.Results: The BEM-FMM toolkit has been successfully modified to accept head models consisting of one unique mesh per unique tissue while still supporting its initial model format of one unique mesh per boundary between two specific tissues. Performance impacts occur in the preprocessing phase only, meaning that the charge computation method performs equally well regardless of model format.

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Strommen, Jeffrey A., and Andrea J. Boon. "Motor Evoked Potentials." In Clinical Neurophysiology, 592–605. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780190259631.003.0033.

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Motor evoked potentials (MEP) may be used in the diagnosis of central and peripheral neurological disorders and have become the standard of care in many operative procedures as a means to monitor the motor pathways.In the awake patient, transcranial magnetic stimulation (TMS) can be utilized with surface or subcutaneous muscle recordings to identify central conduction abnormalities, as well as assist with prognosis, in conditions such as multiple sclerosis, stroke, spinal cord injury, Parkinson’s disease, hereditary spastic paraplegia, or ALS. In the operating theater, transcranial electrical stimulation with recording from the spinal cord, root, peripheral nerve, or muscle can be used to prevent spinal cord damage, determine continuity of roots or peripheral nerves, and assist with surgical planning. MEP are significantly affected by many physiological variables and pharmacological agents. Various techniques in regards to simulation sites, stimulation parameters, and recording techniques and sites need to be modified to enhance the reproducibility and reliability of these responses.

Тези доповідей конференцій з теми "Transcranial simulations":

1

Vyas, Urvi, Elena Kaye, and Kim Butts Pauly. "Transcranial phase aberration correction using beam simulations and MR-ARFI." In 12TH INTERNATIONAL SYMPOSIUM ON THERAPEUTIC ULTRASOUND. AIP, 2012. http://dx.doi.org/10.1063/1.4769941.

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Ding, Zhaohuan, Yang Bai, Hao Zhang, and Xiaoli Li. "Numerical simulations of figure-8 coil during transcranial magnetic stimulation." In 2017 Chinese Automation Congress (CAC). IEEE, 2017. http://dx.doi.org/10.1109/cac.2017.8243136.

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3

Angla, Célestine, Hamza Chouh, Paul Mondou, Gwenael Toullelan, Kévyn Perlin, Emmanuel De Schlichting, Jean-Luc Gennisson, Benoit Larrat, and Sylvain Chatillon. "Fast transcranial ultrasound simulations based on time-of-flight minimization." In 2023 IEEE International Ultrasonics Symposium (IUS). IEEE, 2023. http://dx.doi.org/10.1109/ius51837.2023.10307147.

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Xu, Guanjie, Gaomin Su, Hao Fang, and Yue Li. "Enabling Transcranial Electrical Stimulation via STI01: Experimental Simulations and Hardware Circuit Implementation." In 2023 5th International Conference on Electronic Engineering and Informatics (EEI). IEEE, 2023. http://dx.doi.org/10.1109/eei59236.2023.10212634.

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Gao, Ya, Beatrice Lauber, Beat Werner, Giovanni Colacicco, Daniel Razansky, Qian Cheng, and Héctor Estrada. "Performance of learned pseudo-CT in transcranial ultrasound simulations using fluid and solid skulls." In 2023 IEEE International Ultrasonics Symposium (IUS). IEEE, 2023. http://dx.doi.org/10.1109/ius51837.2023.10306343.

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Jones, Ryan, Meaghan O'Reilly, and Kullervo Hynynen. "Simulations of transcranial passive acoustic mapping with hemispherical sparse arrays using computed tomography-based aberration corrections." In ICA 2013 Montreal. ASA, 2013. http://dx.doi.org/10.1121/1.4800018.

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RAVNIK, JURE, ANNA ŠUŠNJARA, OŽBEJ VERHNJAK, DRAGAN POLJAK, and MARIO CVETKOVIĆ. "COUPLED BOUNDARY ELEMENT: STOCHASTIC COLLOCATION APPROACH FOR THE UNCERTAINTY ESTIMATION OF SIMULATIONS OF TRANSCRANIAL ELECTRIC STIMULATION." In BEM/MRM44. Southampton UK: WIT Press, 2021. http://dx.doi.org/10.2495/be440121.

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Kohtanen, Eetu, Matteo Mazzotti, Massimo Ruzzene, and Alper Erturk. "Leveraging Vibrations and Guided Waves in a Human Skull." In ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-71315.

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Abstract This work is centered on high-fidelity modeling, analysis, and rigorous experiments of vibrations and guided (Lamb) waves in a human skull in two connected tracks: (1) layered modeling of the cranial bone structure (with cortical tables and diploë) and its vibration-based elastic parameter identification (and validation); (2) transcranial leaky Lamb wave characterization experiments and radiation analyses using the identified elastic parameters in a layered semi analytical finite element framework, followed by time transient simulations that consider the inner porosity as is. In the first track, non-contact vibration experiments are conducted to extract the first handful of modal frequencies in the auditory frequency regime, along with the associated damping ratios and mode shapes, of dry cranial bone segments extracted from the parietal and frontal regions of a human skull. Numerical models of the bone segments are built with a novel image reconstruction scheme that employs microcomputed tomographic scans to build a layered bone geometry with separate homogenized domains for the cortical tables and the diploë. These numerical models and the experimental modal frequencies are then used in an iterative parameter identification scheme that yields the cortical and diploic isotropic elastic moduli of each domain, whereas the corresponding densities are estimated using the total experimental mass and layer mass ratios obtained from the scans. With the identified elastic parameters, the average error between experimental and numerical modal frequencies is less than 1.5% and the modal assurance criterion values for most modes are above 0.90. Furthermore, the extracted parameters are in the range of the results reported in the literature. In the second track, the focus is placed on the subject of leaky Lamb waves, which has received growing attention as a promising alternative to conventional ultrasound techniques for transcranial transmission, especially to access the brain periphery. Experiments are conducted on the same cranial bone segment set for leaky Lamb wave excitation and radiation characterization. The degassed skull bone segments are used in submersed experiments with an ultrasonic transducer and needle hydrophone setup for radiation pressure field scanning. Elastic parameters obtained from the first track are used in guided wave dispersion simulations, and the radiation angles are accurately predicted using the aforementioned layered model in the presence of fluid loading. The dominant radiation angles are shown to correspond to guided wave modes with low attenuation and a significant out-of-plane polarization. The experimental radiation spectra are finally compared against those obtained from time transient finite element simulations that leverage geometric models reconstructed from microcomputed tomographic scans.

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Yuan, Yaoshen, Paolo Cassano, Matthew Pias, and Qianqian Fang. "A Simulation Study for Transcranial Photobiomodulation Dosimetry Across Lifespan." In Clinical and Translational Biophotonics. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/translational.2020.tw1b.7.

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Hao, Dongmei, Yanan Zhou, Pei Gao, Lin Yang, Yimin Yang, and Fei Chen. "Simulation Study on Coil Design for Transcranial Magnetic Stimulation*." In 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE, 2018. http://dx.doi.org/10.1109/embc.2018.8512683.

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