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 evoked by a pseudorandomly applied vibration stimulation to the calf muscles. The evoked anteroposterior responses were analyzed with a method considering adaptation in the slow changes in posture and in the stimulus-response relationship. Repetition of examinations on a daily basis revealed a gradual improvement of postural-control performance. The body sway induced by the stimulation was significantly reduced and the dynamical properties changed. Most of the improvements remained after 90 days, but some parameters such as the complexity of the control system used were increased to the initial level. The results confirm previous observations that postural control contains several partially independent adaptive processes, observed in terms of alteration of posture and as a progressive reduction of body sway induced by stimulation. The method used for the adaptation analysis in this study could be applied to analyze biological systems with multiple individual adaptive processes with different time courses or characteristics, or where the adaptation processes are related to multiple internal or external factors.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Fransson PA,Tjernström F,Hafström A,Magnusson M,Johansson Rdoi
10.1007/s00422-001-0305-ykeywords:
subject
Has Abstractpub_date
2002-05-01 00:00:00pages
355-65issue
5eissn
0340-1200issn
1432-0770journal_volume
86pub_type
杂志文章abstract::We analyzed cyclic enzyme systems, one of the best candidates for biochemical switching devices, especially focusing on their control mode against external perturbations. Since these systems have the reliability of ON-OFF types of operation (McCulloch-Pitts' neuronic equation), we shall present here the mechanical dif...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00363938
更新日期:1988-01-01 00:00:00
abstract::This report demonstrates the effectiveness of two processes in constructing simple feedforward networks which perform good transformations on their inputs. Good transformations are characterized by the minimization of two information measures: the information loss incurred with the transformation and the statistical d...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00202569
更新日期:1993-01-01 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
abstract::Among the various possible criteria guiding eye movement selection, we investigate the role of position uncertainty in the peripheral visual field. In particular, we suggest that, in everyday life situations of object tracking, eye movement selection probably includes a principle of reduction of uncertainty. To evalua...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-009-0292-y
更新日期:2009-03-01 00:00:00
abstract::We report on the ability of human observers in judging their direction of translation from sparse, moving random dot patterns for varying extents of 3--D rotation. The observers have to discriminate possible axes of translation with angular separations of 2.5 deg or 5 deg. The field of view is either 20 X 20 deg or 10...
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::Rapidly adapting (RA) currents expressed in dorsal root ganglia somatosensory neurons reduce their amplitude in response to prolonged and/or repeated mechanical stimulation. Both inactivation of mechanotransducer channels and adaptation of the force acting on the channels have been suggested to independently decrease ...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-016-0693-7
更新日期:2016-12-01 00:00:00
abstract::One of the major goals in cellular neurobiology is the meaningful cell classification. However, in cell classification there are many unresolved issues that need to be addressed. Neuronal classification usually starts with grouping cells into classes according to their main morphological features. If one tries to test...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-011-0426-x
更新日期:2011-03-01 00:00:00
abstract::This work presents unified analyses of spatial and temporal visual information processing in a feed-forward network of neurons that obey membrane, or shunting equations. The feed-forward shunting network possesses properties that make it well suited for processing of static, spatial information. However, it is shown h...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00201798
更新日期:1992-01-01 00:00:00
abstract::A receptive field constitutes a region in the visual field where a visual cell or a visual operator responds to visual stimuli. This paper presents a theory for what types of receptive field profiles can be regarded as natural for an idealized vision system, given a set of structural requirements on the first stages o...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-013-0569-z
更新日期:2013-12-01 00:00:00
abstract::Isolated and cultured neonatal cardiac myocytes contract spontaneously and cyclically, and have the properties of a non-linear oscillator. In this study, we have analyzed the relationship between the fluctuation of contraction rhythm of spontaneously beating cultured cardiac myocytes, and the coupling strength among t...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-001-0285-y
更新日期:2002-02-01 00:00:00
abstract::This article describes current views on motor and sensory control of extraocular muscles (EOMs) based on anatomical data. The special morphology of EOMs, including their motor innervation, is described in comparison to classical skeletal limb and trunk muscles. The presence of proprioceptive organs is reviewed with em...
journal_title:Biological cybernetics
pub_type: 杂志文章,评审
doi:10.1007/s00422-012-0519-1
更新日期:2012-12-01 00:00:00
abstract::There are two issues in balancing a stick pivoting on a finger tip (or mechanically on a moving cart): maintaining the stick angle near to vertical and maintaining the horizontal position within the bounds of reach or cart track. The (linearised) dynamics of the angle are second order (although driven by pivot acceler...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-013-0564-4
更新日期:2013-12-01 00:00:00
abstract::Leg movements of stick insects (Carausius morosus) making turns towards visual targets are examined in detail, and a dynamic model of this behaviour is proposed. Initial results suggest that front legs shape most of the body trajectory, while the middle and hind legs just follow external forces (Rosano H, Webb B, in T...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-007-0170-4
更新日期:2007-09-01 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::Several formulations of correlation-based Hebbian learning are reviewed. On the presynaptic side, activity is described either by a firing rate or by presynaptic spike arrival. The state of the postsynaptic neuron can be described by its membrane potential, its firing rate, or the timing of backpropagating action pote...
journal_title:Biological cybernetics
pub_type: 杂志文章,评审
doi:10.1007/s00422-002-0353-y
更新日期:2002-12-01 00:00:00
abstract::A mathematical model of the central neural mechanisms of respiratory rhythm generation is developed. This model assumes that the respiratory cycle consists of three phases: inspiration, post-inspiration, and expiration. Five respiratory neuronal groups are included: inspiratory, late-inspiratory, post-inspiratory, exp...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00203037
更新日期:1990-01-01 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::In the neural superposition eye of a dipteran fly every ommatidium has eight photoreceptors, each associated with a rhabdomere, two central and six peripheral, which altogether result in seven functional light guides. Groups of eight rhabdomeres in neighboring ommatidia have largely overlapping fields of view. Based o...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-006-0097-1
更新日期:2006-11-01 00:00:00
abstract::Following Kohonen and using the Hebb principle, we define a self organizing stochastic process, which is a simple modelization of the retinotopy, i.e. the establishment of well-ordered connexions between the retina and the cortex. We give some mathematical results about convergence of this process. These results are i...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00318206
更新日期:1986-01-01 00:00:00
abstract::The operation of a hierarchical competitive network model (VisNet) of invariance learning in the visual system is investigated to determine how this class of architecture can solve problems that require the spatial binding of features. First, we show that VisNet neurons can be trained to provide transform-invariant di...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s004220100284
更新日期:2002-01-01 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::Saccadic averaging is the phenomenon that two simultaneously presented retinal inputs result in a saccade with an endpoint located on an intermediate position between the two stimuli. Recordings from neurons in the deeper layers of the superior colliculus have revealed neural correlates of saccade averaging, indicatin...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s004220050450
更新日期:1998-06-01 00:00:00
abstract::In primates, it is well known that there is a consistent relationship between the duration, peak velocity and amplitude of saccadic eye movements, known as the 'main sequence'. The reason why such a stereotyped relationship evolved is unknown. We propose that a fundamental constraint on the deployment of foveal vision...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-006-0064-x
更新日期:2006-07-01 00:00:00
abstract::The superior colliculus (SC) integrates relevant sensory information (visual, auditory, somatosensory) from several cortical and subcortical structures, to program orientation responses to external events. However, this capacity is not present at birth, and it is acquired only through interactions with cross-modal eve...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-012-0511-9
更新日期:2012-12-01 00:00:00
abstract::Motion repulsion is the perceived enlargement of the angle between the directions of motion of two transparently moving patterns. An explanation of this illusion has long been sought for in the neural circuitry of the brain. We show that motion repulsion already arises from the statistical properties of the motion tra...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-005-0556-0
更新日期:2005-04-01 00:00:00
abstract::This article compiles an expose of Valentino Braitenberg's singular view on neuroanatomy and neuroscience. The review emphasizes his topologically informed work on neuroanatomy and his dialectics of brain-based explanations of motor behavior. Some of his early ideas on topologically informed neuroanatomy are presented...
journal_title:Biological cybernetics
pub_type: 传,历史文章,杂志文章,评审
doi:10.1007/s00422-012-0533-3
更新日期:2014-10-01 00:00:00
abstract::The proposal that rod outer segment length is optimal with respect to photon absorption and noise control is extended and tested in a number of species. We find good agreement with our optimality criterion in duplex retinae where rods act as detectors of one or a few photons, but not in all rod retinae nor in those wh...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00203666
更新日期:1992-01-01 00:00:00
abstract::The amount of power in different frequency bands of the electroencephalogram (EEG) carries information about the behavioral state of a subject. Hence, neurologists treating epileptic patients monitor the temporal evolution of the different bands. We propose a covariance-based method to detect and characterize epilepti...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-020-00840-y
更新日期:2020-10-01 00:00:00
abstract::Fast as possible (time optimal) single joint movements throughout the body are characterized by the triphasic (3 pulse) pattern of activation in the agonist and antagonist muscles. Simulation studies using a sixth order, non-linear model were undertaken to determine the relationship between time optimal movement and t...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00338824
更新日期:1987-01-01 00:00:00
abstract::The action potentials (impulses) produced by pairs of neighboring retinal ganglion cells often show a tendency either to fire in close temporal synchrony or to avoid temporal synchrony. This cross-correlation (a rate of "coincidences" that differs from that expected by chance) has been exploited as a window into retin...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-004-0492-4
更新日期:2004-09-01 00:00:00