Abstract：
:This paper presents a model for the circadian temporization system of mammals which associates the synchronization dynamics of coupling oscillators to a set of equations able to reproduce the synaptic characteristics of somatodendritic membrane of neurons. The circadian timing system is organized in a way to receive information from the external and internal environments, and its function is the timing organization of physiological and behavioral processes in a circadian pattern. Circadian timing system in mammals is constituted by a group of structures which includes the suprachiasmatic nucleus, the intergeniculate leaflet and the pineal gland. In suprachiasmatic nucleus are found neuron groups working as a biological pacemaker-the so-called biological master clock. By means of numerical simulations using the Kuramoto model, we simulated the dynamics behavior of the biological pacemaker. For this we used a set of 1,000 coupled oscillators with long-range coupling, which were distributed on a 10 x 10 x 10 spherical lattice, and a new method to estimate the order parameter, which characterizes the degree of synchronization of oscillator system. Our model has been able to produce frequency responses in accordance with physiological patterns, and to reproduce two fundamental characteristics of biological rhythms: the endogenous generation and synchronization to the light-dark cycle.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Cardoso FR,de Oliveira Cruz FA,Silva D,Cortez CMdoi
10.1007/s00422-009-0309-6subject
Has Abstractpub_date
2009-05-01 00:00:00pages
385-93issue
5eissn
0340-1200issn
1432-0770journal_volume
100pub_type
杂志文章abstract：:This paper concerns the processing of the outputs of the two opponent-color mechanisms in the human visual system. We present experimental evidence that opponent-color signals interact after joint modulation even though they are essentially independent under neutral steady adaptation and after exclusive modulation of ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：
更新日期：1993-01-01 00:00:00
abstract：:Directional and orientational components usually coexist and are mixed in the cell's overall responses when moving optical stimuli are used to study the response characteristics of visual neurons. While these two properties were quantified with all the previous methods for data analysis, their effects could not be eff...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00197609
更新日期：1994-01-01 00:00:00
abstract：:Diffusion processes have been extensively used to describe membrane potential behavior. In this approach the interspike interval has a theoretical counterpart in the first-passage-time of the diffusion model employed. Since the mathematical complexity of the first-passage-time problem increases with attempts to make t...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201480
更新日期：1995-10-01 00:00:00
abstract：:We consider a simple electronic circuit model of a single neuron. The neuron is assumed to be driven by an external signal comprising constant (dc) and random components. In addition, the nonlinearity parameter in the circuit is assumed to fluctuate, thereby giving rise to critical behavior including the onset of hyst...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00198768
更新日期：1989-01-01 00:00:00
abstract：:Insects can remember and return to a place of interest using the surrounding visual cues. In previous experiments, we showed that crickets could home to an invisible cool spot in a hot environment. They did so most effectively with a natural scene surround, though they were also able to home with distinct landmarks or...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-009-0338-1
更新日期：2009-10-01 00:00:00
abstract：:In bursting excitable cells such as pancreatic beta-cells and molluscan Aplysia neuron cells, intracellular Ca2+ ion plays a central role in various cellular functions. To understand the role of [Ca2+]i (the intracellular Ca2+ concentration) in electrical bursting, we formulate a mathematical model which contains a fe...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00202449
更新日期：1990-01-01 00:00:00
abstract：:One possible strategy for the solution of the correspondence problem of stereo matching is the coarse-to-fine mechanism: The matching process starts with a lowpass-filtered version of the stereogram where only a few, high-contrast image features can be extracted and the probability of false matches is therefore low. I...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00204198
更新日期：1996-02-01 00:00:00
abstract：:The concerted and self-organizing behavior of spinal cord segments in generating locomotor patterns is modulated by afferent sensory information and controlled by descending pathways from the brainstem, cerebellum, or cortex. The purpose of this study was to define a minimal set of parameters that could control a simi...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-002-0335-0
更新日期：2003-01-01 00:00:00
abstract：:After a brief description of the main anatomical structures subserving the oculomotor responses during combined vestibular and optokinetic stimulations, a mathematical model is presented. With respect to a previous model by Schmid et al. (1980), a more accurate definition of the roles of the neural mechanisms involved...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00319980
更新日期：1982-01-01 00:00:00
abstract：:Arthropods as well as mammals are able to return straight home after a random search excursion under conditions that are designed to exclude all external cues. After a brief clarification of the terminology, two principal systems of information processing that can achieve this performance are introduced and analysed: ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220000169
更新日期：2000-09-01 00:00:00
abstract：:We study the dynamics of a system of coupled nonlinear oscillators that has been used to model coordinated human movement behavior. In contrast to earlier work we examine the case where the two component oscillators have different eigenfrequencies. Problems related to the decomposition of a time series (from an experi...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00199134
更新日期：1996-01-01 00:00:00
abstract：:Neuronal excitability under stimuli with a complex time course is investigated on the basis of the numerical solution of the Hodgkin-Huxley equations. Each stimulus is composed of 100-1000 unitary excitatory postsynaptic potentials (uEPSP) that start randomly within a definite time window. Probability of initiating a ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00209424
更新日期：1996-06-01 00:00:00
abstract：:Based on the kinematics of goal-directed aiming movements in a reciprocal Fitts' task, a minimal limit cycle model is proposed that is capable of producing the behavior observed at levels of task difficulty ranging from 3 to 7. From graphical and statistical analyses of the phase planes, Hooke's planes and velocity pr...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050521
更新日期：1999-04-01 00:00:00
abstract：:A fundamental problem in neuroscience, to which Prof. Segundo has made seminal contributions, is to understand how action potentials represent events in the external world. The aim of this paper is to review the issue of neural coding in the context of the rodent whiskers, an increasingly popular model system. Key iss...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-008-0290-5
更新日期：2009-06-01 00:00:00
abstract：:Temporal information processing was studied in humans attempting to tap a key in synchrony with a metronome whose base period was subjected to subliminal random changes. Statistical measures of the sequential timing of metronome and key-tap events were compared with similar time series generated by computer-simulated ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00319511
更新日期：1987-01-01 00:00:00
abstract：:Many tasks require the arm to move from its initial position to a specified target position, but leave us free to choose the trajectory between them. This paper presents and tests the hypothesis that trajectories are chosen to minimize metabolic energy costs. Costs are calculated for the range of possible trajectories...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050324
更新日期：1997-02-01 00:00:00
abstract：:The evolutionary transition from water to land required new locomotor modes and corresponding adjustments of the spinal "central pattern generators" for locomotion. Salamanders resemble the first terrestrial tetrapods and represent a key animal for the study of these changes. Based on recent physiological data from sa...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-012-0538-y
更新日期：2013-10-01 00:00:00
abstract：:In this article, we present a neurologically motivated computational architecture for visual information processing. The computational architecture's focus lies in multiple strategies: hierarchical processing, parallel and concurrent processing, and modularity. The architecture is modular and expandable in both hardwa...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0597-3
更新日期：2014-06-01 00:00:00
abstract：:The aim of this paper is to summarize and to compare some known mathematical models of orientation perception in random dot patterns and to propose new solutions of this question. The model adequacy is judged from the previously obtained experimental results. Apart from the models based on some simple function of the ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00202455
更新日期：1990-01-01 00:00:00
abstract：:The generation of informational sequences and their reorganization or reshaping is one of the most intriguing subjects for both neuroscience and the theory of autonomous intelligent systems. In spite of the diversity of sequential activities of sensory, motor, and cognitive neural systems, they have many similarities ...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-006-0121-5
更新日期：2006-12-01 00:00:00
abstract：:Beck (1972, 1973) hypothesized that textural segmentation occurs strongly on the basis of simple properties such as brightness, color, size, and the slopes of contours and lines of the elemental descriptors of a texture or textural elements. The experiment reported supports the hypothesis that specific stimulus featur...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00344396
更新日期：1983-01-01 00:00:00
abstract：:An "adaptation model" having two stages is introduced and its mathematical properties are examined. The two stages are the "adaptive process" (parameter Kb), which has bleaching-type kinetics, and the "response function" (parameters Kr and n), which incorporates response saturation. In order to study the increment thr...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00361040
更新日期：1978-09-28 00:00:00
abstract：:Taste buds endure extreme changes in temperature, pH, osmolarity, so on. Even though taste bud cells are replaced in a short span, they contribute to consistent taste reception. Each taste bud consists of about 50 cells whose networks are assumed to process taste information, at least preliminarily. In this article, w...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-011-0447-5
更新日期：2011-07-01 00:00:00
abstract：:This article analyzes the question of whether neuroscience allows for mathematical descriptions and whether an interaction between experimental and theoretical neuroscience can be expected to benefit both of them. It is argued that a mathematization of natural phenomena never happens by itself. First, appropriate key ...
journal_title：Biological cybernetics
pub_type： 历史文章,杂志文章
doi：10.1007/s00422-014-0609-3
更新日期：2014-10-01 00:00:00
abstract：:A model is presented which accounts for many characteristic response properties used to classify anuran ganglion cell types while being consistent with data concerning interneurons. In the model color is ignored and input stimuli are assumed to be only black and white at high contrast. We show that accurate ganglion c...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201980
更新日期：1991-01-01 00:00:00
abstract：:We employ an optimal solution to both the "shape from motion problem" and the related problem of the estimation of self-movement on a purely optical basis to deduce practical rules of thumb for the limits of the optic flow information content in the presence of perturbation of the motion parallax field. The results ar...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00365219
更新日期：1987-01-01 00:00:00
abstract：:Using the theory of random point processes, a method is presented whereby functional relationships between neurons can be detected and modeled. The method is based on a point process characterization involving stochastic intensities and an additive rate function model. Estimates are based on the maximum likelihood (ML...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00332915
更新日期：1988-01-01 00:00:00
abstract：:A method that enables measurement of the degree of coupling between two signals is presented. The method is based on the definition of an uncoupling function calculating, by means of entropy rates, the minimum amount of independent information (i.e. the information carried by one signal which cannot be derived from th...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050549
更新日期：1999-08-01 00:00:00
abstract：:Depolarization of an excitable membrane has a dual effect; excitatory in that it causes rapid opening of calcium and/or sodium channels but inhibitory in that it also causes those channels to inactivate. We considered whether apparently paradoxical or dual behavior might be exhibited by excitatory and inhibitory synap...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00197289
更新日期：1991-01-01 00:00:00
abstract：:A pacemaker cell pair model and the dynamic interaction between the two pacemaker cells is described in this paper. It is an extension of our single pacemaker cell model, in which we studied its response to repetitive external depolarization stimulations. This model is a simple model based on the two most important fu...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050460
更新日期：1998-07-01 00:00:00
