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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">mathematics</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник российских университетов. Математика</journal-title><trans-title-group xml:lang="en"><trans-title>Russian Universities Reports. Mathematics</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2686-9667</issn><issn pub-type="epub">2782-3342</issn><publisher><publisher-name>Тамбовский государственный университет имени Г.Р. Державина</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.20310/2686-9667-2021-26-135-271-295</article-id><article-id custom-type="elpub" pub-id-type="custom">mathematics-193</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>СТАТЬИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ARTICLES</subject></subj-group></article-categories><title-group><article-title>Существование и устойчивость периодических решений уравнения нейронного поля</article-title><trans-title-group xml:lang="en"><trans-title>Existence and stability of periodic solutions in a neural field equation</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Колодина</surname><given-names>Карина</given-names></name><name name-style="western" xml:lang="en"><surname>Kolodina</surname><given-names>Karina</given-names></name></name-alternatives><email xlink:type="simple">karina.a.kolodina@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кострыкин</surname><given-names>Вадим</given-names></name><name name-style="western" xml:lang="en"><surname>Kostrykin</surname><given-names>Vadim</given-names></name></name-alternatives><email xlink:type="simple">noemail@neicon.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Олейник</surname><given-names>Анна</given-names></name><name name-style="western" xml:lang="en"><surname>Oleynik</surname><given-names>Anna</given-names></name></name-alternatives><email xlink:type="simple">anna.oleynik@uib.no</email><xref ref-type="aff" rid="aff-3"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Норвежский университет естественных наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Norwegian University of Life Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Университет Майнца</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Johannes Gutenberg University of Mainz</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Бергенский университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>University of Bergen</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>12</day><month>10</month><year>2021</year></pub-date><volume>26</volume><issue>135</issue><fpage>271</fpage><lpage>295</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Колодина К., Кострыкин В., Олейник А., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Колодина К., Кострыкин В., Олейник А.</copyright-holder><copyright-holder xml:lang="en">Kolodina K., Kostrykin V., Oleynik A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://mathematics.elpub.ru/jour/article/view/193">https://mathematics.elpub.ru/jour/article/view/193</self-uri><abstract><p>В статье изучаются существование и устойчивость стационарных периодических решений модели нейронного поля, а именно интегрально-дифференциального уравнения типа Гаммерштейна. Полагая, что функция активации - ступенчатая функция, а ядро оператора - быстроубывающая функция, мы формулируем необходимые и достаточные условия существования особого класса решений - 1-бамповые (выпуклые) периодические решения. Далее мы изучаем устойчивость этих решений с помощью спектра производной Фреше соответствующего оператора Гаммерштейна. Мы доказываем, что этот спектр согласуется с точностью до нуля со спектром блочного оператора Лорана. Также показываем, что ненулевой спектр состоит только из собственных значений, и получаем аналитические выражения, как для собственных значений, так и для собственных функций. Кроме того в статье рассмотрены примеры.</p></abstract><trans-abstract xml:lang="en"><p>We study the existence and linear stability of stationary periodic solutions to a neural field model, an intergo-differential equation of the Hammerstein type. Under the assumption that the activation function is a discontinuous step function and the kernel is decaying sufficiently fast, we formulate necessary and sufficient conditions for the existence of a special class of solutions that we call 1-bump periodic solutions. We then analyze the stability of these solutions by studying the spectrum of the Frechet derivative of the corresponding Hammerstein operator. We prove that the spectrum of this operator agrees up to zero with the spectrum of a block Laurent operator. We show that the non-zero spectrum consists of only eigenvalues and obtain an analytical expression for the eigenvalues and the eigenfunctions. The results are illustrated by multiple examples.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>нелинейные интегральные уравнения</kwd><kwd>сигмоивидная функция активации</kwd><kwd>модель нейронного поля</kwd><kwd>периодические решения</kwd><kwd>блочные операторы Лорана</kwd></kwd-group><kwd-group xml:lang="en"><kwd>nonlinear integral equations</kwd><kwd>sigmoid type nonlinearities</kwd><kwd>neural field model</kwd><kwd>periodic solutions</kwd><kwd>block Laurent operators</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Shun-ichi Amari, “Dynamics of pattern formation in lateral-inhibition type neural fields”, Biological Cybernetics, 27:2 (1977), 77-87.</mixed-citation><mixed-citation xml:lang="en">Shun-ichi Amari, “Dynamics of pattern formation in lateral-inhibition type neural fields”, Biological Cybernetics, 27:2 (1977), 77-87.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">S. 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