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 few functionally important ionic currents in the excitable cells. In this model, inactivation of Ca2+ current takes place by a mixture of voltage and intracellular Ca2+ ions. The model predicts that, although the electrical bursting patterns look the same, the shapes of [Ca2+]i oscillations could be very different depending on how fast [Ca2+]i changes in the cytosolic free space (i.e., how strong the cellular Ca2+ buffering capacity is). If [Ca2+]i changes fast, [Ca2+]i oscillates in bursts in parallel to electrical bursting such that it reaches a maximum at the onset of bursting and a minimum just after the termination of the plateau phase. If the change is slow, then [Ca2+]i oscillates out-of-phase with electrical bursting such that it peaks at a maximum near the termination of the plateau and a minimum just before the onset of the active phase. During the active phase [Ca2+]i gradually increases without spikes. In the intermediate ranges, [Ca2+]i oscillates in such a manner that the peak of [Ca2+]i oscillation lags behind the electrical activity. The model also predicts the existence of multipeaked oscillations and chaos in certain ranges of the gating variables and the intracellular Ca2+ buffer concentration.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Chay TRdoi
10.1007/BF00202449subject
Has Abstractpub_date
1990-01-01 00:00:00pages
15-23issue
1eissn
0340-1200issn
1432-0770journal_volume
63pub_type
杂志文章abstract：:Neurons in sensory cortices are often assumed to be "feature detectors", computing simple and then successively more complex features out of the incoming sensory stream. These features are somehow integrated into percepts. Despite many years of research, a convincing candidate for such a feature in primary auditory co...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-003-0445-3
更新日期：2003-11-01 00:00:00
abstract：:In neural networks the activation process controls the output as a nonlinear function of the input; and, this output remains bounded between limits as decided by a logistic function known as the sigmoid (S-shaped). Presently, by applying the considerations of Maxwell-Boltzmann statistics, the Langevin function is show...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00216966
更新日期：1991-01-01 00:00:00
abstract：:The contrast threshold elevation effect has been measured for one dimensional (grating) and for two dimensional (spot) stimulus patterns. It has been shown previously (Burton and Ruddock, 1978) that such stimuli elicit, respectively, non-length-selective and length-selective adaptation effects. It is established that,...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00337369
更新日期：1978-11-10 00:00:00
abstract：:This paper deals with the problem of representing and generating unconstrained aiming movements of a limb by means of a neural network architecture. The network produced time trajectories of a limb from a starting posture toward targets specified by sensory stimuli. Thus the network performed a sensory-motor transform...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF02414903
更新日期：1989-01-01 00:00:00
abstract：:The dynamic response of the human ankle joint to a bandlimited random torque perturbation superimposed on a constant bias torque is observed in normal human subjects. The applied torque input, the joint angular rotation output, and the electromyographic activity using surface electrodes from the extensor and the flexo...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00357923
更新日期：1984-01-01 00:00:00
abstract：:A neural model is proposed for the spatiotemporal properties of simple cells in the visual cortex. In the model, several cortical cells are arranged on a ring, with mutual excitatory or inhibitory connections. The cells also receive excitatory inputs either from lagged and nonlagged cells of the lateral geniculate nuc...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050383
更新日期：1997-10-01 00:00:00
abstract：:This paper deals with the problem of separating the spectra of signal and noise in ensembles where the signal can be considered as an invariant component and the noise as a stationary additive background. Several methods are discussed and compared on the basis of a statistical analysis of the first two moments of the ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00337392
更新日期：1979-03-19 00:00:00
abstract：:Highly-interconnected networks of nonlinear analog neurons are shown to be extremely effective in computing. The networks can rapidly provide a collectively-computed solution (a digital output) to a problem on the basis of analog input information. The problems to be solved must be formulated in terms of desired optim...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00339943
更新日期：1985-01-01 00:00:00
abstract：:Neurons receive a continual stream of excitatory and inhibitory synaptic inputs. A conductance-based neuron model is used to investigate how the balanced component of this input modulates the amplitude of neuronal responses. The output spiking rate is well described by a formula involving three parameters: the mean mu...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-003-0408-8
更新日期：2003-08-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-015-0670-6
更新日期：2016-02-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-003-0432-8
更新日期：2004-01-01 00:00:00
abstract：:In recent years, a great deal of research within the field of sound localization has been aimed at finding the acoustic cues that human listeners use to localize sounds and understanding the mechanisms by which they process these cues. In this paper, we propose a complementary approach by constructing an ideal-observe...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0588-4
更新日期：2014-04-01 00:00:00
abstract：:Recent results demonstrate techniques for fully quantitative, statistical inference of the dynamics of individual neurons under the Hodgkin-Huxley framework of voltage-gated conductances. Using a variational approximation, this approach has been successfully applied to simulated data from model neurons. Here, we use t...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0615-5
更新日期：2014-08-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00449594
更新日期：1985-01-01 00:00:00
abstract：:Compared to all other hearing animals, insects are the smallest ones, both in absolute terms and in relation to the wavelength of most biologically relevant sounds. The ears of insects can be located at almost any possible body part, such as wings, legs, mouthparts, thorax or abdomen. The interaural distances are gene...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-015-0672-4
更新日期：2016-10-01 00:00:00
abstract：:The response of a healthy lateral eye of Limulus to constant, uniform and sufficiently intense light stimulation, consists of a sustained oscillatory discharge, all ommatidia firing synchronously in bursts, at intervals of about 0.2s (Barlow and Fraioli, 1978). This response has been analysed by a computer simulation,...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00336944
更新日期：1980-01-01 00:00:00
abstract：:Panoramic image differences can be used for view-based homing under natural outdoor conditions, because they increase smoothly with distance from a reference location (Zeil et al., J Opt Soc Am A 20(3):450-469, 2003). The particular shape, slope and depth of such image difference functions (IDFs) recorded at any one p...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-007-0147-3
更新日期：2007-05-01 00:00:00
abstract：:The myoskeletal inverse dynamics problem and the myocybernetic control inverse problem were investigated with respect to their ill-posedness. The first problem consists of finding from observed experimental motion and reaction force data the resultant muscle moments that generated the observed motion, while the second...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050013
更新日期：2000-02-01 00:00:00
abstract：:Goal directed movements, executed by means of a manipulator with various dynamics, were investigated in order to establish to what extent the loading affects the executed movement. The desired movement concept, together with a describing function model for goal directed movements, was applied to parameterize the movem...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00336183
更新日期：1984-01-01 00:00:00
abstract：:Many neurons at the sensory periphery receive periodic input, and their activity exhibits entrainment to this input in the form of a preferred phase for firing. This article describes a modeling study of neurons which skip a random number of cycles of the stimulus between firings over a large range of input intensitie...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00198810
更新日期：1994-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00318721
更新日期：1987-01-01 00:00:00
abstract：:The effect of spatial frequency discrimination learning on spatial frequency detection tuning curves, obtained by a summation to threshold paradigm, has been investigated. Three human observers were exposed to a grating discrimination task for longer than two weeks, and their detection thresholds for compound Gabor gr...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/PL00007983
更新日期：2001-05-01 00:00:00
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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：:A new method is presented for quantitative evaluation of single-sweep phase and amplitude electro-encephalogram (EEG) characteristics that is a more informative approach in comparison with conventional signal averaging. In the averaged potential, phase-locking and amplitude effects of the EEG response cannot be separa...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050335
更新日期：1997-03-01 00:00:00
abstract：:The idea that a sparse representation is the computational principle of visual systems has been supported by Olshausen and Field [Nature (1996) 381: 607-609] and many other studies. On the other hand neurons in the inferotemporal cortex respond to moderately complex features called icon alphabets, and such neurons res...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220000149
更新日期：2000-08-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00199590
更新日期：1991-01-01 00:00:00
abstract：:Computational and behavioral studies suggest that visual motion discrimination is based on quadratic nonlinearities. This raises the question of whether the behavior of motion sensitive neurons early in the visual system is actually quadratic. Theoretical studies show that mechanisms proposed for retinal directional s...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00203629
更新日期：1990-01-01 00:00:00
abstract：:Between the extreme views concerning ontogenesis (genetic vs. environmental determination), we use a moderate approach: a somehow pre-established neuronal model network reacts to activity deviations (reflecting input to be compensated), and stabilizes itself during a complex feed-back process. Morphogenesis is based o...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00318417
更新日期：1986-01-01 00:00:00
abstract：:The short-term (i.e., days) and long-term (i.e., months) effects of adaptation to posturography examinations were investigated in 12 normal subjects who were repeatedly examined for five consecutive days and again after 90 days. The examinations were conducted both with eyes open and closed, and the perturbations were...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-001-0305-y
更新日期：2002-05-01 00:00:00
abstract：:1. Results from the companion paper were incorporated into a physiologically realistic computer model of the three principal cell types (PD/AB, LP, PY) of the pyloric network in the stomatogastric ganglion. Parameters for the model were mostly calculated (sometimes estimated) from experimental data rather than fitting...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00337411
更新日期：1979-08-01 00:00:00
