Mechanisms explaining transitions between tonic and phasic firing in neuronal populations as predicted by a low dimensional firing rate model

Several firing patterns experimentally observed in neural populations have been successfully correlated to animal behavior. Population bursting, hereby regarded as a period of high firing rate followed by a period of quiescence, is typically observed in groups of neurons during behavior. Biophysical membrane-potential models of single cell bursting involve at least three equations. Extending such models to study the collective behavior of neural populations involves thousands of equations and can be very expensive computationally. For this reason, low dimensional population models that capture biophysical aspects of networks are needed. \noindent The present paper uses a firing-rate model to study mechanisms that trigger and stop transitions between tonic and phasic population firing. These mechanisms are captured through a two-dimensional system, which can potentially be extended to include interactions between different areas of the nervous system with a small number of equations. The typical behavior of midbrain dopaminergic neurons in the rodent is used as an example to illustrate and interpret our results. \noindent The model presented here can be used as a building block to study interactions between networks of neurons. This theoretical approach may help contextualize and understand the factors involved in regulating burst firing in populations and how it may modulate distinct aspects of behavior.Comment: 25 pages (including references and appendices); 12 figures uploaded as separate file

АТЛАС СПЕКТРОВ ГАЗОРАЗРЯДНОЙ ЛАМПЫ ДВС-25 В ДИАПАЗОНЕ 320-1100 НМ

Gas discharge hydrogen DVS-25 lamp is frequently used as a source of continuous spectrum in the range of 190-360 nm as well as a radiator of hydrogen atomic and molecular lines in the longer-wave region of the spectrum. The striped spectrum of molecular hydrogen has several thousand of H2 lines in the range of 330-1100 nm that can be resolved by the different spectral line devices. In the specified range, the DVS-25 lamp can be used as a source of the spectrum with a very high density of lines, and it can effectively be used for the calibration of spectral scales of spectrographs equipped with photoelectronic cassettes on linear charge coupled devices. In our work, the spectrum measurement of the DVS-25 lamp was performed in the range of 330-1100 nm using the spectrograph PGS-2 (dispersion of 0.73 nm/mm) equipped with a photoelectronic cassette on 6 linear charge coupled devices. For the spectrum in the above specified range, an atlas of the DVS-25 spectrum was created. The wavelengths of H and H2 lines registered in the DVS-25 spectrum with a value of s/n exceeding 5 were added to the database of spectral lines of the atlas. The number of lines in this atlas exceeds 2600. The density of H2 lines emitted by the DVS-25 in the range of 450-1000 nm is significantly higher than the density of Fe and Ne lines in the emission of LT-3 lamp with a hollow cathode. A large number of lines in the DVS-25 emission allows very accurately calibrate a small desired area of the spectrum in typical mini-spectrometers designed to measure the wavelength of laser diode sources with a precision better than 0.001 nm.Key words: charge-coupled devices, spectrographs, the spectrum of the atlas, photoelectron cassette, hydrogen gas discharge lampDOI: http://dx.doi.org/10.15826/analitika.2017.21.2.003E.G. Silkis1, A.S. Stankevich1, A.V. Shonenkov2 1Institute of Spectroscopy, of the Russian Academy of Sciences, Fizicheskaya ul., 5, Troitsk, Moscow; 108840, Russian Federation2Joint Institute for High Temperatures, of the Russian Academy of Sciences, ul.  Izhorskaya, 13, structure 2, Moscow, 125412, Russian FederationГазоразрядная водородная лампа ДВС-25 используется как источник непрерывного спектра в диапазоне 190-360 нм, сильных атомных и молекулярных линий водорода в более длинноволновой области спектра (400-700 нм). Спектр молекулярного водорода H2 в диапазоне 330-1100 нм имеет несколько тысяч линий, разрешаемых спектральными приборами с дисперсией 0.2-0.8 нм/мм. В указанном диапазоне лампа ДВС-25 может эффективно применяться как источник линейчатого спектра с очень высокой плотностью линий для калибровки спектральных шкал спектрографов, оснащенных фотоэлектронными кассетами на линейных приборах с зарядовой связью. В данной работе проведено измерение линейчатого спектра лампы ДВС-25 в диапазоне 330-1100 нм с помощью спектрографа PGS-2 (дисперсия 0.73 нм/мм) и фотоэлектронной кассеты на 6 линейных приборах с зарядовой связью. Для указанного диапазона составлен атлас спектров ДВС-25. Длины волн линий Н и H2, зарегистрированных в спектре ДВС-25 с соотношением сигнал/шум, превышающем 5, внесены в базу спектральных линий этого атласа. Количество идентифицированных линий в атласе составляет 2955. Плотность спектральных линий H2 излучения ДВС-25 в диапазоне 450-1000 нм существенно выше плотности линий Fe и Ne излучения лампы ЛТ-3 с полым катодом. Большое количество линий излучения ДВС-25 позволяет откалибровать небольшую нужную область спектра в типовых мини-спектрометрах, предназначенных для измерения длины волны лазерных диодных источников, с точностью лучше чем 0.001 нм.Ключевые слова: приборы с зарядовой связью (ПЗС), спектрографы, атлас спектров, фотоэлектронные кассеты, газоразрядная водородная  лампа.DOI: http://dx.doi.org/10.15826/analitika.2017.21.2.00

Atlas spectrum of gas discharge DVS-25 lamp in the range of 320-1100 nm

Gas discharge hydrogen DVS-25 lamp is frequently used as a source of continuous spectrum in the range of 190-360 nm as well as a radiator of hydrogen atomic and molecular lines in the longer-wave region of the spectrum. The striped spectrum of molecular hydrogen has several thousand of H2 lines in the range of 330-1100 nm that can be resolved by the different spectral line devices. In the specified range, the DVS-25 lamp can be used as a source of the spectrum with a very high density of lines, and it can effectively be used for the calibration of spectral scales of spectrographs equipped with photoelectronic cassettes on linear charge coupled devices. In our work, the spectrum measurement of the DVS-25 lamp was performed in the range of 330-1100 nm using the spectrograph PGS-2 (dispersion of 0.73 nm/mm) equipped with a photoelectronic cassette on 6 linear charge coupled devices. For the spectrum in the above specified range, an atlas of the DVS-25 spectrum was created. The wavelengths of H and H2 lines registered in the DVS-25 spectrum with a value of s/n exceeding 5 were added to the database of spectral lines of the atlas. The number of lines in this atlas exceeds 2600. The density of H2 lines emitted by the DVS-25 in the range of 450-1000 nm is significantly higher than the density of Fe and Ne lines in the emission of LT-3 lamp with a hollow cathode. A large number of lines in the DVS-25 emission allows very accurately calibrate a small desired area of the spectrum in typical mini-spectrometers designed to measure the wavelength of laser diode sources with a precision better than 0.001 nm.Газоразрядная водородная лампа ДВС-25 используется как источник непрерывного спектра в диапазоне 190-360 нм, а также сильных атомных и молекулярных линий водорода в более длинноволновой области спектра (400-700 нм). Спектр молекулярного водорода H2 в диапазоне 330-1100 нм имеет несколько тысяч линий, разрешаемых спектральными приборами с дисперсией 0.2-0.8 нм/мм. В указанном диапазоне лампа ДВС-25 может эффективно применяться как источник линей чатого спектра с очень высокой плотностью линий для калибровки спектральных шкал спектрографов, оснащенных фотоэлектронными кассетами на линейных приборах с зарядовой связью. В данной работе проведено измерение линейчатого спектра лампы ДВС-25 в диапазоне 330-1100 нм с помощью спектрографа PGS-2 (дисперсия 0.73 нм/мм) и фотоэлектронной кассеты на 6 линейных приборах с зарядовой связью. Для указанного диапазона составлен атлас спектров ДВС-25. Длины волн линий Н и H2, зарегистрированных в спектре ДВС-25 с соотношением сигнал/шум, превышающем 5, внесены в базу спектральных линий этого атласа. Количество идентифицированных линий в атласе составляет 2962. Плотность спектральных линий H2 излучения ДВС-25 в диапазоне 450-1000 нм существенно выше плотности линий Fe и Ne излучения лампы ЛТ-3 с полым катодом. Большое количество линий излучения ДВС-25 позволяет откалибровать небольшую нужную область спектра в типовых мини-спектрометрах, предназначенных для измерения длины волны лазерных диодных источников, с точностью не хуже чем 0.001 нм

A perspective on neural and cognitive mechanisms of error commission

Behavioral adaptation and cognitive control are crucial for goal-reaching behaviors. Every creature is ubiquitously faced with choices between behavioral alternatives. Common sense suggests that errors are an important source of information in the regulation of such processes. Several theories exist regarding cognitive control and the processing of undesired outcomes. However, most of these models focus on the consequences of an error, and less attention has been paid to the mechanisms that underlie the commissioning of an error. In this article, we present an integrative review of neuro-cognitive models that detail the determinants of the occurrence of response errors. The factors that may determine the likelihood of committing errors are likely related to the stability of task-representations in prefrontal networks, attentional selection mechanisms and mechanisms of action selection in basal ganglia circuits. An important conclusion is that the likelihood of committing an error is not stable over time but rather changes depending on the interplay of different functional neuro-anatomical and neuro-biological systems. We describe factors that might determine the time-course of cognitive control and the need to adapt behavior following response errors. Finally, we outline the mechanisms that may proof useful for predicting the outcomes of cognitive control and the emergence of response errors in future research