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Mutual information spectrum for selection of event-related spatial components. Application to eloquent motor cortex mapping
Frontiers in Neuroinformatics. 2014. Vol. 7.
Spatial component analysis is often used to explore multidimensional time series data whose sources cannot be measured directly. Several methods may be used to decompose the data into a set of spatial components with temporal loadings. Component selection is of crucial importance, and should be supported by objective criteria. In some applications, the use of a well defined component selection criterion may provide for automation of the analysis. In this paper we describe a novel approach for ranking of spatial components calculated from the EEG or MEG data recorded within evoked response paradigm. Our method is called Mutual Information (MI) Spectrum and is based on gauging the amount of MI of spatial component temporal loadings with a synthetically created reference signal. We also describe the appropriate randomization based statistical assessment scheme that can be used for selection of components with statistically significant amount of MI. Using simulated data with realistic trial to trial variations and SNR corresponding to the real recordings we demonstrate the superior performance characteristics of the described MI based measure as compared to a more conventionally used power driven gauge. We also demonstrate the application of the MI Spectrum for the selection of task-related independent components from real MEG data. We show that the MI spectrum allows to identify task-related components reliably in a consistent fashion, yielding stable results even from a small number of trials. We conclude that the proposed method fits naturally the information driven nature of ICA and can be used for routine and automatic ranking of independent components calculated from the functional neuroimaging data collected within event-related paradigms.
Language:
English
Publication based on the results of:
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In this paper the structural stability of generic families of vector fields of the PC-HC class on the two-dimensional sphere is proved. A classification of these families up to moderate equivalence in neighborhoods of their large bifurcation supports is presented, based on such invariants as the configuration and the characteristic set. The realization lemma is proved. ...
Added: May 14, 2026
Lebedev V., Journal of Mathematical Analysis and Applications 2026 Vol. 563 No. 2 Article 130787
It is known that for every continuous real-valued
function $f$ on the circle $\mathbb T=\mathbb R/2\pi\mathbb Z$ there exists a
change of variable, i.e., a self-homeomorphism $h$ of $\mathbb T$, such that
the superposition $f\circ h$ is in the Sobolev space $W_2^{1/2}(\mathbb T)$.
We obtain new results on simultaneous improvement of functions by a single
change of variable in relation ...
Added: May 14, 2026
Gaeva D. V., Barinova G. M., Romanchuk A. Y., Theoretical and Applied Climatology 2026 Vol. 157 Article 302
The objective of the paper was the spatio-temporal analysis of the dynamics of extreme climate indices for the south-eastern coast of the Baltic Sea over the 40-year period 1981–2020, employing 10 extreme indices proposed by Expert Team (ET) on Climate Change Detection and Indices (ETCCDI), characterizing hazardous phenomena as: extremely high temperatures, heat waves and ...
Added: May 13, 2026
Mkrtchyan N. V., Известия РАН. Серия географическая 2026 Т. 90 № 1 С. 231–245
Objective of the study is to assess the provision of all settlements in four regions of the Russian Near
North (Vologda, Kostroma, Kirov, and Yaroslavl oblasts) with social infrastructure facilities and to
analyze whether the migration balance of settlements is associated with varying levels of provision of
these facilities. The study is based on data collected from open ...
Added: May 13, 2026
Blokh A., Oversteegen L., Selinger N. et al., Arnold Mathematical Journal 2025 Vol. 12 No. 1 P. 1–40
We describe a model for the boundary of the connectedness locus of the parameter space of cubic symmetric polynomials. We show that there exists a monotone continuous function from the connectedness locus to the model which is a homeomorphism if the former is locally connected. ...
Added: May 13, 2026
Petrov I., Автоматика и телемеханика 2026 № 6 С. 82–118
Системам связанных агентов и сетевому управлению посвящено большое число отечественных и зарубежных исследований. Исторически, наибольший интерес в теории управления возникал к усредняющим системам и, в частности, к задаче консенсуса. Однако сетевое взаимодействие может характеризоваться более специфическими функциями, отражающими зависимость от действий соседей по сети, что особенно явно проявляется в моделях стратегического взаимодействия на сети, которое ...
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Gerges M., Kosonogov V., OBM Neurobiology 2025 Vol. 9 No. 4 Article 310
Emotion regulation (ER) involves processes by which individuals modulate the intensity, duration, and expression of emotional responses, and its dysregulation is associated with a broad spectrum of psychological disorders. While traditionally conceptualized within psychological frameworks, ER is increasingly recognized as biologically grounded, involving intricate interactions between neurochemical, hormonal, and metabolic systems. This narrative review aims ...
Added: May 12, 2026
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В настоящем сборнике представлены тезисы докладов участников семинара "Интеграция основного и дополнительного физико-математического образования", проходившего 11 февраля 2026 года в ГБОУ Школа №2007 ФМШ г. москвы, а также другие публикации, посвящённые вопросам дополнительного физико-математического образования. ...
Added: May 11, 2026
Novikov R., Sivkin V., Inverse Problems 2026 Vol. 42 No. 4 Article 045009
We consider a plane wave, a radiation solution, and the sum of these solutions (total solution) for
the Helmholtz equation in an exterior region in Rd, d ⩾ 2. In this region, we consider a hyperplane X with sufficiently large distance s from the origin in Rd. We give two-point local formulas
for approximate recovering the radiation ...
Added: May 11, 2026
Hecht M., Hofmann P., Wicaksono D. et al., IMA Journal of Numerical Analysis 2026 Vol. 00 P. 1–30
Recent advances in Bernstein—Walsh theory have extended Bernstein’s Theorem to multiple dimensions, stating that a multivariate function can be approximated with a geometric rate in a downward-closed polynomial space if and only if it is analytic in a generalized Bernstein polyellipse. To compute approximations of this class of functions—which we term Bos–Levenberg–Trefethen–(BLT) functions—we extend the ...
Added: May 11, 2026
Kelbert M., Kalimulina E. Y., Entropy 2026 Vol. 28 Article 536
We study binary hypothesis testing for i.i.d. observations under a multiplicative context
weight. For the optimal weighted total loss, defined as the sum of weighted type-I and typeII losses, we prove the logarithmic asymptotic L∗n = exp{−nDwC (P,Q) + o(n)}, n →∞, where Dw
C is the weighted Chernoff information. The single-letter form of the exponent
relies on ...
Added: May 7, 2026
Белоусов Н. М., Черепанов Л. К., Деркачов С. Э. et al., Selecta Mathematica, New Series 2026 Vol. 32 Article 44
We prove equivalence of two integral representations for the wave functions of hyperbolic Calogero–Sutherland system. For this we study two families of Baxter operators related to hyperbolic Calogero–Sutherland and rational Ruijsenaars models; the first one as a limit from hyperbolic Ruijsenaars system, while the second one independently. Besides, computing asymptotics of integral representations and also ...
Added: May 6, 2026
Муравьев М. Ю., Annales Mathematiques du Quebec 2025
Recently Rohleder proposed a new variational approach to an inequality between the Neumann and Dirichlet eigenvalues in the simply connected planar case using the language of classical vector analysis. Interpreting his approach in terms of differential forms permits to generalize these results to a much broader context. The spectrum of the absolute boundary problem for ...
Added: May 6, 2026
Цыганов А. В., Порубов Е. О., Теоретическая и математическая физика 2026 Т. 227 № 2 С. 336–355
Теория тензорных инвариантов обыкновенных дифференциальных уравнений и классификация Картана простых алгебр Ли используется для установления изоморфизма задачи Козлова о движении ферромагнетика в магнитном поле и задачи Шоттки о движении четырехмерного твердого тела. Найдены новые полиномиальные и рациональные бивекторы Пуассона, инвариантные либо относительно пары коммутирующих фазовых потоков, либо относительно одного из пары потоков. ...
Added: May 5, 2026
Feurra M., Perevoznyuk G., Ragimova A. et al., Scientific Reports 2026 No. 16 Article 13098 (2026)
Motor imagery (MI) allows individuals to mentally simulate movements without execution, engaging neural pathways that overlap with those used during real actions. However, how imagery perspective influences corticospinal excitability across different effectors remains unclear. Using neuronavigated transcranial magnetic stimulation (TMS), we compared kinesthetic (KMI), first-person visual (VMI-1PP), and third-person visual (VMI-3PP) imagery of elbow flexion-extension ...
Added: May 5, 2026
Зайцев А. И., Pelinovsky E., Костенко И. С. et al., Морской гидрофизический журнал 2026 Т. 42 № 2 С. 263–274
Purpose. The purpose of this study is to investigate the parameters of the Kamchatka tsunami induced by the earthquake of July 29 (30), 2025, off the Kamchatka Peninsula, and its manifestations on the northern coast of Shumshu Island (Northern Kuril Islands), based on field survey results and numerical simulations. Methods and Results. The results of ...
Added: May 4, 2026
Монахова Э. А., Монахов О. Г., Rzaev E. et al., Прикладная дискретная математика 2026 Т. 71 С. 112–127
В настоящей работе исследовано совместное конструирование топологий семейств оптимальных по диаметру циркулянтных сетей $C(N; \pm 1, \pm s_2)$ и реализуемых для них оптимальных алгоритмов маршрутизации сложности $O(1)$. Предлагаемый алгоритм маршрутизации основан на использовании масштабируемых параметров $L$-образных шаблонов плотной укладки графов на плоскости для семейств оптимальных сетей.
Определены аналитические формулы зависимости этих параметров от диаметра графов семейств ...
Added: May 4, 2026
Chepovskiy A., Chepovskiy A., Успехи кибернетики 2025 Т. 6 № 1 С. 55–61
In this paper, the authors study the problem of both assessing the quality of implicit community detection on a graph obtained by importing data from social networks and instant messengers, and methods for analyzing such networks to identify the information impact on its actors. Two approaches to assessing the correctness of dividing a graph into ...
Added: May 23, 2025
Pechenkova E., Паникратова Я. Р., Мершина Е. А. et al., Медицинская визуализация 2022 Т. 26 № 1 С. 48–69
Presurgical brain mapping of language-eloquent cortex aims to minimize its injury during neurosurgery in patients with brain tumors and drug-resistant epilepsy, and thereby, to preserve their quality of life. Two main goals of language mapping are to identify the localization and lateralization of brain regions involved in language. Gold standards for them are the intraoperative ...
Added: March 24, 2022
Leydesdorff L., Ivanova I., Journal of the Association for Information Science and Technology 2021 Vol. 72 No. 4 P. 387–402
Problem solving often requires crossing boundaries, such as those between disciplines. When policy‐makers call for “interdisciplinarity,” however, they often mean “synergy.” Synergy is generated when the whole offers more possibilities than the sum of its parts. An increase in the number of options above the sum of the options in subsets can be measured as ...
Added: October 30, 2020
Ivanov F., Kreshchuk A., Rybin P. et al., , in: The 11th International Congress on Ultra Modern Telecommunications and Control Systems (ICUMT 2019).: Dublin: IEEE, 2019. P. 1–5.
Added: October 1, 2019
Kelbert M., Suhov Y., Stuhl I., Modern Stochastics: Theory and Applications 2017 Vol. 4 No. 3 P. 233–252
This paper represents an extended version of an earlier note [10]. The concept of
weighted entropy takes into account values of different outcomes, i.e., makes entropy contextdependent,
through the weight function. We analyse analogs of the Fisher information inequality
and entropy power inequality for the weighted entropy and discuss connections with
weighted Lieb’s splitting inequality. The concepts of rates ...
Added: October 10, 2017
Ossadtchi A., Journal of Neuroscience Methods 2012 Vol. 207 No. 1 P. 1–16
Connectivity measures are (typically bivariate) statistical measures that may be used to estimate interactions between brain regions from electrophysiological data. We review both formal and informal descriptions of a range of such measures, suitable for the analysis of human brain electrophysiological data, principally electro- and magnetoencephalography. Methods are described in the space–time,space–frequency, and space–time–frequency domains. ...
Added: October 23, 2014
Alexei Ossadtchi, Pronko P. K., Baillet S. et al., Frontiers in Neuroinformatics 2014 Vol. 7 No. January P. Article 53
Spatial component analysis is often used to explore multidimensional time series data whose sources cannot be measured directly. Several methods may be used to decompose the data into a set of spatial components with temporal loadings. Component selection is of crucial importance, and should be supported by objective criteria. In some applications, the use of ...
Added: January 29, 2014